Variable frequency heat pump unit, control method and device thereof, storage medium and program product

Abstract

The invention discloses a variable-frequency heat pump unit and a control method and device thereof, a storage medium and a computer program product, and the method comprises the steps that a high-pressure pressure threshold value and a high-pressure protection pressure threshold value of a compressor are controlled according to a block diagram of the compressor, and the high-pressure pressure range of the compressor is determined; after the variable frequency heat pump unit is powered on and the compressor is started, the current high pressure of the compressor is obtained, and the current frequency of the compressor is obtained; and according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, the current frequency of the compressor is controlled, so that the current high-pressure pressure of the compressor is adjusted to be within the high-pressure pressure range of the compressor. According to the scheme, the high-pressure pressure threshold value and the high-pressure protection pressure threshold value are controlled according to the block diagram of the compressor to determine the high-pressure pressure range, and control such as frequency limiting and frequency reduction is carried out on the current frequency of the compressor, so that the high-pressure pressure of the compressor is controlled within the set reasonable pressure range, and the reliability and safety of unit operation are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of variable frequency heat pump units, and specifically relates to a control method and device for a variable frequency heat pump unit, a variable frequency heat pump unit, a storage medium and a computer program product. Background Art

[0002] With the development of the heat pump market, heat pumps have completely moved towards variable frequency. How to control the pressure range of variable frequency units and ensure the reliability of compressors has become an urgent problem that needs to be solved.

[0003] In related schemes, the pressure range control of the variable frequency heat pump unit is generally achieved by limiting the frequency reduction of the unit by exceeding a certain high pressure threshold to maintain the high pressure level. However, the high pressure threshold in this method is relatively simple, which may cause the unit to frequently enter high pressure protection and affect the reliable operation of the unit.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The object of the present invention is to provide a control method, device, variable frequency heat pump unit, storage medium and computer program product for a variable frequency heat pump unit, so as to solve the problem that the pressure range control of the variable frequency heat pump unit is generally to limit the frequency of the unit to maintain the high pressure level by exceeding a certain high pressure threshold, but it is easy to cause the high pressure protection of the unit to occur frequently, affecting the reliable operation of the unit. The purpose is to achieve at least one protection of limiting the frequency of the compressor, reducing the frequency at normal speed, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, rapid frequency reduction and high pressure protection to control the high pressure pressure of the compressor within a set reasonable pressure range, thereby improving the reliability and safety of the unit operation.

[0006] The present invention provides a control method for a variable frequency heat pump unit, wherein the variable frequency heat pump unit has a compressor; the control method for the variable frequency heat pump unit comprises: obtaining a block diagram control high-pressure pressure threshold of the compressor, and obtaining a high-pressure protection pressure threshold of the compressor; determining a high-pressure pressure range of the compressor according to the block diagram control high-pressure pressure threshold of the compressor and the high-pressure protection pressure threshold of the compressor; after the variable frequency heat pump unit is powered on and the compressor is turned on, obtaining a current high-pressure pressure of the compressor and obtaining a current frequency of the compressor; and controlling the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor to adjust the current high-pressure pressure of the compressor to within the high-pressure pressure range of the compressor.

[0007] In some embodiments, the high-pressure range of the compressor is determined according to the high-pressure pressure threshold controlled by the block diagram of the compressor and the high-pressure protection pressure threshold of the compressor, including: determining the difference between the high-pressure pressure threshold controlled by the block diagram of the compressor and a preset first pressure threshold as the frequency-limited high-pressure pressure threshold of the compressor; determining the difference between the high-pressure pressure threshold controlled by the block diagram of the compressor and a preset second pressure threshold as the first rate-reduced high-pressure pressure threshold of the compressor; determining the sum of the high-pressure pressure threshold controlled by the block diagram of the compressor and a preset third pressure threshold as the second rate-reduced high-pressure pressure threshold of the compressor; and determining the high-pressure protection threshold of the compressor as the second rate-reduced high-pressure pressure threshold of the compressor. The pressure threshold, and the difference between the preset fourth pressure threshold, are determined as the third rate frequency reduction high-pressure pressure threshold of the compressor; the fourth rate frequency reduction high-pressure pressure threshold of the compressor is determined by the difference between the high-pressure protection pressure threshold of the compressor and the preset fifth pressure threshold; the high-pressure pressure range of the compressor is determined according to the frequency-limited high-pressure pressure threshold of the compressor, the block diagram control high-pressure pressure threshold of the compressor, the first rate frequency reduction high-pressure pressure threshold of the compressor, the second rate frequency reduction high-pressure pressure threshold of the compressor, the third rate frequency reduction high-pressure pressure threshold of the compressor, the fourth rate frequency reduction high-pressure pressure threshold of the compressor, and the high-pressure protection pressure threshold of the compressor.

[0008] In some embodiments, the high-pressure pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor, which are successively increased; controlling the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, including: determining whether it is continuously detected within a first set time in a preset frequency-limited mode that the current high-pressure pressure of the compressor is greater than or equal to the frequency-limited high-pressure pressure threshold of the compressor, and is less than the first rate frequency reduction high-pressure pressure threshold of the compressor; if it is determined that it is continuously detected within a first set time in the preset frequency-limited mode that the current high-pressure pressure of the compressor is greater than or equal to the frequency-limited high-pressure pressure threshold of the compressor, and is less than the first rate frequency reduction high-pressure pressure threshold of the compressor, If the first rate frequency reduction high-pressure pressure threshold of the compressor is reached, the compressor is controlled to enter a preset frequency limiting mode to limit the increase of the current frequency of the compressor; then it is determined whether the current high-pressure pressure of the compressor is detected to be less than the frequency limiting high-pressure pressure threshold of the compressor continuously within the second set time under the preset frequency limiting mode; if it is determined that the current high-pressure pressure of the compressor is detected to be less than the frequency limiting high-pressure pressure threshold of the compressor continuously within the second set time under the preset frequency limiting mode, then after maintaining the current frequency of the compressor for the third set time under the preset frequency limiting mode, the compressor is controlled to exit the preset frequency limiting mode to exit limiting the increase of the current frequency of the compressor and resume the control of the increase and decrease of the current frequency of the compressor; if it is determined that the current high-pressure pressure of the compressor is not detected to be less than the frequency limiting high-pressure pressure threshold of the compressor continuously within the second set time under the preset frequency limiting mode, then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor.

[0009] In some embodiments, the high-pressure pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor; controlling the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, and also including: determining whether the frequency reduction is continuously performed at a preset first rate. If it is determined that the current high-pressure pressure of the compressor is greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and is less than the block diagram control high-pressure pressure threshold of the compressor within the first set time in the preset first rate frequency reduction mode, the compressor is controlled to enter the preset first rate frequency reduction mode to control the current frequency of the compressor to reduce the preset first rate frequency reduction value; then it is re-determined whether the first set time in the preset first rate frequency reduction mode is continuously detected. If it is detected within a certain time that the current high-pressure pressure of the compressor is greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and is less than the block diagram control high-pressure pressure threshold of the compressor: if so, the current frequency of the compressor is controlled to be reduced by the preset first rate frequency reduction value at every preset first rate frequency reduction time; otherwise, the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; after controlling the current frequency of the compressor to be reduced by the preset first rate frequency reduction value at every preset first rate frequency reduction time, it is determined whether it is continuously detected within the second set time in the preset first rate frequency reduction mode The current high-pressure pressure of the compressor is less than the first rate frequency reduction high-pressure pressure threshold of the compressor; if it is determined that the current high-pressure pressure of the compressor is detected to be less than the first rate frequency reduction high-pressure pressure threshold of the compressor continuously within the second set time in the preset first rate frequency reduction mode, then after maintaining the current frequency of the compressor in the preset first rate frequency reduction mode for a third set time, the compressor is controlled to exit the preset first rate frequency reduction mode, so as to exit the current frequency reduction control of the compressor according to the preset first rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor;If it is determined that the current high pressure pressure of the compressor is not detected to be less than the first rate frequency reduction high pressure pressure threshold of the compressor within the second set time in the preset first rate frequency reduction mode, then return to control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor. ;

[0010] In some embodiments, the high-pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor; controlling the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, further comprising: determining whether the current frequency of the compressor is continuously within a preset range. It is detected within the first set time under the block diagram control mode that the current high pressure pressure of the compressor is greater than or equal to the block diagram control high pressure pressure threshold of the compressor, and is less than the second rate frequency reduction high pressure pressure threshold of the compressor; if it is determined that the current high pressure pressure of the compressor is detected within the first set time under the preset block diagram control mode to be greater than or equal to the block diagram control high pressure pressure threshold of the compressor, and is less than the second rate frequency reduction high pressure pressure threshold of the compressor, then the compressor is controlled to enter the preset block diagram control mode to control the current frequency of the compressor to reduce the preset block diagram control frequency reduction value; then it is re-determined whether it is continuously in the preset block diagram control mode If it is detected within the first set time under the present high-pressure pressure of the compressor that the current high-pressure pressure of the compressor is greater than or equal to the block diagram control high-pressure pressure threshold of the compressor and less than the second rate frequency reduction high-pressure pressure threshold of the compressor: if so, the current frequency of the compressor is controlled to be reduced by the preset block diagram control frequency reduction value at every preset block diagram control time; otherwise, the present frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; after the current frequency of the compressor is controlled to be reduced by the preset block diagram control frequency reduction value at every preset block diagram control time, it is determined whether the second set value under the preset block diagram control mode is continuously controlled. If it is determined that the current high-pressure pressure of the compressor is less than the block diagram control high-pressure pressure threshold of the compressor within a second set time continuously within the preset block diagram control mode, then after maintaining the current frequency of the compressor for a third set time under the preset block diagram control mode, the compressor is controlled to exit the preset block diagram control mode to exit the current frequency reduction of the compressor controlled according to the preset block diagram control mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor;If it is determined that the current high pressure pressure of the compressor is not detected to be less than the block diagram control high pressure pressure threshold of the compressor within the second set time in the preset block diagram control mode, and it is determined that the current high pressure pressure of the compressor is not detected to be less than the block diagram control high pressure pressure threshold of the compressor within the continuous control time in the preset block diagram control mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop. ;

[0011] In some embodiments, the high-pressure pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor; wherein, according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, controlling the current frequency of the compressor also includes: determining whether the frequency reduction is continuously performed at a preset second rate. If it is determined that the current high pressure pressure of the compressor is greater than or equal to the second rate frequency reduction high pressure pressure threshold of the compressor and is less than the third rate frequency reduction high pressure pressure threshold of the compressor within the first set time in the preset second rate frequency reduction mode, the compressor is controlled to enter the preset second rate frequency reduction mode to control the current frequency of the compressor to reduce the preset second rate frequency reduction value; then it is re-determined whether the current high pressure pressure of the compressor is greater than or equal to the second rate frequency reduction high pressure pressure threshold of the compressor and is less than the third rate frequency reduction high pressure pressure threshold of the compressor within the first set time in the preset second rate frequency reduction mode. If it is detected within a set time that the current high-pressure pressure of the compressor is greater than or equal to the second rate frequency reduction high-pressure pressure threshold of the compressor and is less than the third rate frequency reduction high-pressure pressure threshold of the compressor, then if so, the current frequency of the compressor is controlled to be reduced by the preset second rate frequency reduction value at every preset second rate frequency reduction time; otherwise, the control is returned to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; after controlling the current frequency of the compressor to be reduced by the preset second rate frequency reduction value at every preset second rate frequency reduction time, it is determined whether the current high-pressure pressure of the compressor is continuously detected within the second set time in the preset second rate frequency reduction mode. It is detected that the current high-pressure pressure of the compressor is less than the second rate frequency reduction high-pressure pressure threshold of the compressor; if it is determined that the current high-pressure pressure of the compressor is detected to be less than the second rate frequency reduction high-pressure pressure threshold of the compressor continuously within the second set time in the preset second rate frequency reduction mode, then after maintaining the current frequency of the compressor in the preset second rate frequency reduction mode for a third set time, the compressor is controlled to exit the preset second rate frequency reduction mode, so as to exit the current frequency reduction control of the compressor according to the preset second rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor;If it is determined that the current high-pressure pressure of the compressor is not detected to be less than the second rate-reduction high-pressure pressure threshold of the compressor within the second set time in the preset second rate-reduction frequency mode, and it is determined that the current high-pressure pressure of the compressor is not detected to be less than the second rate-reduction high-pressure pressure threshold of the compressor within the continuous control time in the preset second rate-reduction frequency mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop;

[0012] And / or, controlling the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, further comprising: determining whether it is continuously detected within the first set time in the preset third-rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the third-rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the fourth-rate frequency reduction high-pressure pressure threshold of the compressor; if it is determined that it is continuously detected within the first set time in the preset third-rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the third-rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the fourth-rate frequency reduction high-pressure pressure threshold of the compressor , the compressor is controlled to enter a preset third rate frequency reduction mode to control the current frequency of the compressor to reduce the preset third rate frequency reduction value; then it is re-determined whether it is continuously detected within the first set time in the preset third rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the third rate frequency reduction high-pressure pressure threshold of the compressor and less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor: if so, the current frequency of the compressor is controlled to reduce the preset third rate frequency reduction value at every preset third rate frequency reduction time; otherwise, it returns to re-according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, frequency is controlled; after controlling the current frequency of the compressor to reduce the preset third rate frequency reduction value at every preset third rate frequency reduction time, determining whether it is continuously detected that the current high-pressure pressure of the compressor is less than the third rate frequency reduction high-pressure pressure threshold of the compressor within the third set time under the preset third rate frequency reduction mode; if it is determined that the current high-pressure pressure of the compressor is continuously detected to be less than the third rate frequency reduction high-pressure pressure threshold of the compressor within the third set time under the preset third rate frequency reduction mode, then after maintaining the current frequency of the compressor for a fourth time under the preset third rate frequency reduction mode, controlling the compressor to exit the preset third rate frequency reduction mode, so as to Exit the control of the current frequency reduction of the compressor according to the preset third rate frequency reduction mode, and then re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; if it is determined that the current high pressure pressure of the compressor is not continuously detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the third set time in the preset third rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not continuously detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the continuous control time in the preset third rate frequency reduction mode, then control the compressor to stop, and control the variable frequency heat pump unit to stop;

[0013] And / or, controlling the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, further comprising: determining whether it is continuously detected within a first set time in a preset fourth-rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to a fourth-rate frequency reduction high-pressure pressure threshold of the compressor, and is less than a high-pressure protection high-pressure pressure threshold of the compressor; if it is determined that it is continuously detected within a first set time in the preset fourth-rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the fourth-rate frequency reduction high-pressure pressure threshold of the compressor, and is less than a high-pressure protection high-pressure pressure threshold of the compressor, Then the compressor is controlled to enter a preset fourth rate frequency reduction mode to control the current frequency of the compressor to reduce the preset fourth rate frequency reduction value; then it is re-determined whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the fourth rate frequency reduction high-pressure pressure threshold of the compressor and less than the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time in the preset fourth rate frequency reduction mode: if so, the current frequency of the compressor is controlled to reduce the preset fourth rate frequency reduction value at every preset fourth rate frequency reduction time; otherwise, it returns to re-control the current high-pressure pressure of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor. frequency is controlled; after controlling the current frequency of the compressor to reduce the preset fourth rate frequency reduction value at every preset fourth rate frequency reduction time, determining whether it is continuously detected that the current high-pressure pressure of the compressor is less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor within a fourth time under the preset fourth rate frequency reduction mode; if it is determined that the current high-pressure pressure of the compressor is continuously detected to be less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor within a fourth time under the preset fourth rate frequency reduction mode, then after maintaining the current frequency of the compressor for the fourth time under the preset fourth rate frequency reduction mode, controlling the compressor to exit the preset fourth rate frequency reduction mode to exit The compressor is controlled to reduce the frequency according to the preset fourth rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; if it is determined that the current high pressure pressure of the compressor is not continuously detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the fourth time under the preset fourth rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not continuously detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the continuous control time under the preset fourth rate frequency reduction mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop;

[0014] And / or, controlling the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, also includes: determining whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time under the preset high-pressure protection mode; if it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time under the preset high-pressure protection mode, then controlling the high-pressure switch of the variable frequency heat pump unit to disconnect, and controlling the variable frequency heat pump unit to shut down.

[0015] Matching the above method, the present invention provides a control device for a variable frequency heat pump unit on the other hand, the variable frequency heat pump unit having a compressor; the control device for the variable frequency heat pump unit comprises: an acquisition unit configured to acquire a block diagram control high-pressure pressure threshold of the compressor and acquire a high-pressure protection pressure threshold of the compressor; a control unit configured to determine a high-pressure pressure range of the compressor according to the block diagram control high-pressure pressure threshold of the compressor and the high-pressure protection pressure threshold of the compressor; the acquisition unit is further configured to acquire a current high-pressure pressure of the compressor and a current frequency of the compressor after the variable frequency heat pump unit is powered on and the compressor is turned on; the control unit is further configured to control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor to adjust the current high-pressure pressure of the compressor to within the high-pressure pressure range of the compressor.

[0016] In some embodiments, the control unit determines the high-pressure range of the compressor according to the high-pressure pressure threshold controlled by the block diagram of the compressor and the high-pressure protection pressure threshold of the compressor, including: determining the difference between the high-pressure pressure threshold controlled by the block diagram of the compressor and a preset first pressure threshold as the frequency-limited high-pressure pressure threshold of the compressor; determining the difference between the high-pressure pressure threshold controlled by the block diagram of the compressor and a preset second pressure threshold as the first rate-reduced high-pressure pressure threshold of the compressor; determining the sum of the high-pressure pressure threshold controlled by the block diagram of the compressor and a preset third pressure threshold as the second rate-reduced high-pressure pressure threshold of the compressor; and determining the high-pressure pressure threshold controlled by the block diagram of the compressor and a preset third pressure threshold as the second rate-reduced high-pressure pressure threshold of the compressor. The third rate frequency reduction high-pressure pressure threshold of the compressor is determined by the difference between the high-pressure protection pressure threshold of the compressor and the preset fourth pressure threshold; the fourth rate frequency reduction high-pressure pressure threshold of the compressor is determined by the difference between the high-pressure protection pressure threshold of the compressor and the preset fifth pressure threshold; the high-pressure pressure range of the compressor is determined according to the frequency-limited high-pressure pressure threshold of the compressor, the block diagram control high-pressure pressure threshold of the compressor, the first rate frequency reduction high-pressure pressure threshold of the compressor, the second rate frequency reduction high-pressure pressure threshold of the compressor, the third rate frequency reduction high-pressure pressure threshold of the compressor, the fourth rate frequency reduction high-pressure pressure threshold of the compressor, and the high-pressure protection pressure threshold of the compressor.

[0017] In some embodiments, the high-pressure pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor, which are successively increased; the control unit controls the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, including: determining whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the frequency-limited high-pressure pressure threshold of the compressor and less than the first rate frequency reduction high-pressure pressure threshold of the compressor continuously within a first set time in a preset frequency-limited mode; if it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the frequency-limited high-pressure pressure threshold of the compressor continuously within a first set time in a preset frequency-limited mode, and If the pressure drop is less than the first rate frequency reduction high-pressure pressure threshold of the compressor, the compressor is controlled to enter a preset frequency limiting mode to limit the increase of the current frequency of the compressor; then it is determined whether the current high-pressure pressure of the compressor is detected to be less than the frequency limiting high-pressure pressure threshold of the compressor continuously within the second set time under the preset frequency limiting mode; if it is determined that the current high-pressure pressure of the compressor is detected to be less than the frequency limiting high-pressure pressure threshold of the compressor continuously within the second set time under the preset frequency limiting mode, then after maintaining the current frequency of the compressor for the third set time under the preset frequency limiting mode, the compressor is controlled to exit the preset frequency limiting mode to exit limiting the increase of the current frequency of the compressor and resume the control of the increase and decrease of the current frequency of the compressor; if it is determined that the current high-pressure pressure of the compressor is not detected to be less than the frequency limiting high-pressure pressure threshold of the compressor continuously within the second set time under the preset frequency limiting mode, then it is returned to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor.

[0018] In some embodiments, the high-pressure pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor; the control unit controls the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, and also includes: determining whether the current frequency of the compressor is continuously increased within a preset first It is detected that the current high-pressure pressure of the compressor is greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and is less than the block diagram control high-pressure pressure threshold of the compressor within a first set time in a rate frequency reduction mode; if it is determined that the current high-pressure pressure of the compressor is greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and is less than the block diagram control high-pressure pressure threshold of the compressor continuously within a first set time in the preset first rate frequency reduction mode, the compressor is controlled to enter the preset first rate frequency reduction mode to control the current frequency of the compressor to reduce the preset first rate frequency reduction value; then it is re-determined whether it is continuously in the preset first rate frequency reduction mode If it is detected within the first set time that the current high-pressure pressure of the compressor is greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and is less than the block diagram control high-pressure pressure threshold of the compressor: if so, the current frequency of the compressor is controlled to be reduced by the preset first rate frequency reduction value at intervals of the preset first rate frequency reduction time; otherwise, the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; after controlling the current frequency of the compressor to be reduced by the preset first rate frequency reduction value at intervals of the preset first rate frequency reduction time, it is determined whether it is detected continuously within the second set time under the preset first rate frequency reduction mode. It is detected that the current high-pressure pressure of the compressor is less than the first rate frequency reduction high-pressure pressure threshold of the compressor; if it is determined that the current high-pressure pressure of the compressor is detected to be less than the first rate frequency reduction high-pressure pressure threshold of the compressor continuously within the second set time in the preset first rate frequency reduction mode, then after maintaining the current frequency of the compressor in the preset first rate frequency reduction mode for a third set time, the compressor is controlled to exit the preset first rate frequency reduction mode, so as to exit the current frequency reduction of the compressor controlled according to the preset first rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor;If it is determined that the current high pressure pressure of the compressor is not detected to be less than the first rate frequency reduction high pressure pressure threshold of the compressor within the second set time in the preset first rate frequency reduction mode, then return to control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor. ;

[0019] In some embodiments, the high-pressure pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor; the control unit controls the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, and also includes: determining whether to connect If it is determined that the current high-pressure pressure of the compressor is greater than or equal to the block diagram control high-pressure pressure threshold of the compressor and less than the second rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time under the preset block diagram control mode, the compressor is controlled to enter the preset block diagram control mode to control the current frequency of the compressor to reduce the preset block diagram control frequency reduction value; then it is re-determined whether it is continuously under the preset block diagram control mode. If it is detected within the first set time in the control mode that the current high-pressure pressure of the compressor is greater than or equal to the block diagram control high-pressure pressure threshold of the compressor and is less than the second rate frequency reduction high-pressure pressure threshold of the compressor: if so, the current frequency of the compressor is controlled to be reduced by the preset block diagram control frequency reduction value at every preset block diagram control time; otherwise, the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; after the current frequency of the compressor is controlled to be reduced by the preset block diagram control frequency reduction value at every preset block diagram control time, it is determined whether it is continuously controlled within the second set time in the preset block diagram control mode. If it is determined that the current high-pressure pressure of the compressor is less than the block diagram control high-pressure pressure threshold of the compressor within a predetermined time, and if it is determined that the current high-pressure pressure of the compressor is less than the block diagram control high-pressure pressure threshold of the compressor within a second predetermined time under the preset block diagram control mode, then after maintaining the current frequency of the compressor for a third predetermined time under the preset block diagram control mode, the compressor is controlled to exit the preset block diagram control mode, so as to exit the current frequency reduction of the compressor controlled according to the preset block diagram control mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor;If it is determined that the current high pressure pressure of the compressor is not detected to be less than the block diagram control high pressure pressure threshold of the compressor within the second set time in the preset block diagram control mode, and it is determined that the current high pressure pressure of the compressor is not detected to be less than the block diagram control high pressure pressure threshold of the compressor within the continuous control time in the preset block diagram control mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop. ;

[0020] In some embodiments, the high-pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor; wherein the control unit controls the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, and further includes: determining whether the current frequency of the compressor is continuously within a preset range. It is detected within the first set time in the second rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the second rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the third rate frequency reduction high-pressure pressure threshold of the compressor; if it is determined that the current high-pressure pressure of the compressor is detected within the first set time in the preset second rate frequency reduction mode to be greater than or equal to the second rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the third rate frequency reduction high-pressure pressure threshold of the compressor, the compressor is controlled to enter the preset second rate frequency reduction mode to control the current frequency of the compressor to reduce the preset second rate frequency reduction value; then it is re-determined whether it is continuously in the preset second rate frequency reduction mode It is detected within the first set time under the formula that the current high-pressure pressure of the compressor is greater than or equal to the second rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the third rate frequency reduction high-pressure pressure threshold of the compressor: if so, the current frequency of the compressor is controlled to be reduced by the preset second rate frequency reduction value at every preset second rate frequency reduction time; otherwise, the current frequency of the compressor is returned to be controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; after controlling the current frequency of the compressor to be reduced by the preset second rate frequency reduction value at every preset second rate frequency reduction time, it is determined whether it is continuously in the second set time in the preset second rate frequency reduction mode If it is determined that the current high-pressure pressure of the compressor is detected to be less than the second rate frequency reduction high-pressure pressure threshold of the compressor within the second set time in the preset second rate frequency reduction mode, then after maintaining the current frequency of the compressor for a third set time in the preset second rate frequency reduction mode, the compressor is controlled to exit the preset second rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset second rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor;If it is determined that the current high-pressure pressure of the compressor is not detected to be less than the second rate-reduction high-pressure pressure threshold of the compressor within the second set time in the preset second rate-reduction frequency mode, and it is determined that the current high-pressure pressure of the compressor is not detected to be less than the second rate-reduction high-pressure pressure threshold of the compressor within the continuous control time in the preset second rate-reduction frequency mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop;

[0021] And / or, the control unit controls the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, and also includes: determining whether it is continuously detected within the first set time in the preset third rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the third rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor; if it is determined that the current high-pressure pressure of the compressor is continuously detected within the first set time in the preset third rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the third rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor If the third rate reduction pressure threshold is reached, the compressor is controlled to enter a preset third rate reduction frequency reduction mode to control the current frequency of the compressor to reduce the preset third rate reduction frequency reduction value; then it is re-determined whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the third rate reduction high-pressure pressure threshold of the compressor and less than the fourth rate reduction high-pressure pressure threshold of the compressor within a first set time in the preset third rate reduction frequency reduction mode: if so, the current frequency of the compressor is controlled to reduce the preset third rate reduction frequency reduction value at every preset third rate reduction time; otherwise, the compressor is returned to be re-controlled according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor. The present frequency of the compressor is controlled; after controlling the present frequency of the compressor to reduce the preset third rate frequency reduction value at every preset third rate frequency reduction time, determining whether it is continuously detected that the present high pressure pressure of the compressor is less than the third rate frequency reduction high pressure pressure threshold of the compressor within the third setting time in the preset third rate frequency reduction mode; if it is determined that it is continuously detected that the present high pressure pressure of the compressor is less than the third rate frequency reduction high pressure pressure threshold of the compressor within the third setting time in the preset third rate frequency reduction mode, then after maintaining the present frequency of the compressor for a fourth time in the preset third rate frequency reduction mode, controlling the compressor to exit the preset third rate frequency reduction mode. , to exit the frequency reduction of the current frequency of the compressor controlled according to the preset third rate frequency reduction mode, and then re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; if it is determined that the current high pressure pressure of the compressor is not continuously detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the third set time in the preset third rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not continuously detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the continuous control time in the preset third rate frequency reduction mode, then control the compressor to stop, and control the variable frequency heat pump unit to stop;

[0022] And / or, the control unit controls the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, and also includes: determining whether it is continuously detected within the first set time in the preset fourth rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the fourth rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the high-pressure protection high-pressure pressure threshold of the compressor; if it is determined that the current high-pressure pressure of the compressor is continuously detected within the first set time in the preset fourth rate frequency reduction mode that the current high-pressure pressure is greater than or equal to the fourth rate frequency reduction high-pressure pressure threshold of the compressor, and is less than the high-pressure protection high-pressure pressure threshold of the compressor pressure threshold, the compressor is controlled to enter a preset fourth rate frequency reduction mode to control the current frequency of the compressor to reduce the preset fourth rate frequency reduction value; then it is re-determined whether it is continuously detected within the first set time in the preset fourth rate frequency reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the fourth rate frequency reduction high-pressure pressure threshold of the compressor and is less than the high-pressure protection high-pressure pressure threshold of the compressor: if so, the current frequency of the compressor is controlled to reduce the preset fourth rate frequency reduction value at every preset fourth rate frequency reduction time; otherwise, it returns to re-control the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor. the compressor is controlled to control the current frequency of the compressor; after controlling the current frequency of the compressor to reduce the preset fourth rate frequency reduction value at every preset fourth rate frequency reduction time, determining whether it is continuously detected that the current high-pressure pressure of the compressor is less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor within a fourth time under the preset fourth rate frequency reduction mode; if it is determined that the current high-pressure pressure of the compressor is continuously detected to be less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor within a fourth time under the preset fourth rate frequency reduction mode, then after maintaining the current frequency of the compressor for the fourth time under the preset fourth rate frequency reduction mode, controlling the compressor to exit the preset fourth rate frequency reduction mode, The control of the current frequency reduction of the compressor in the preset fourth rate frequency reduction mode is exited, and then the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; if it is determined that the current high pressure pressure of the compressor is not continuously detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the fourth time in the preset fourth rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not continuously detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the continuous control time in the preset fourth rate frequency reduction mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop;

[0023] And / or, the control unit controls the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, and also includes: determining whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time under the preset high-pressure protection mode; if it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time under the preset high-pressure protection mode, then the high-pressure switch of the variable frequency heat pump unit is controlled to be disconnected, and the variable frequency heat pump unit is controlled to be shut down.

[0024] Matching the above device, the present invention provides a variable frequency heat pump unit on another aspect, including: the control device of the variable frequency heat pump unit mentioned above.

[0025] Matching the above method, the present invention provides a storage medium on another aspect, wherein the storage medium includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the steps of the control method of the variable frequency heat pump unit described above.

[0026] Matching the above method, the present invention further provides a computer program product, including a computer program, which implements the steps of the control method of the variable frequency heat pump unit described above when executed by a processor.

[0027] Therefore, the scheme of the present invention pre-sets the pressure intervals corresponding to the seven-fold pressure control of frequency limiting, normal speed frequency reduction, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, and high-pressure protection for the variable frequency heat pump unit, and sets different compressor frequency reduction amplitudes and residence times for each pressure interval; after the compressor of the variable frequency heat pump unit is turned on, the high-pressure pressure of the compressor is obtained, and according to the pressure interval to which the high-pressure pressure of the compressor belongs, the compressor is subjected to at least one of frequency limiting, normal speed frequency reduction, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, and high-pressure protection, so as to control the high-pressure pressure of the compressor within the set reasonable pressure range; thereby, the high-pressure pressure of the compressor is controlled within the set reasonable pressure range by performing at least one of frequency limiting, normal speed frequency reduction, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, and high-pressure protection on the compressor, thereby improving the reliability and safety of the unit operation.

[0028] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention.

[0029] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic flow chart of an embodiment of a control method for a variable frequency heat pump unit of the present invention;

[0031] Figure 2 A schematic diagram of a flow chart of an embodiment of determining the high pressure range of the compressor in the method of the present invention;

[0032] Figure 3 It is a flow chart of an embodiment of pressure control in a preset frequency limiting mode (such as a high-pressure frequency limiting mode) in the method of the present invention;

[0033] Figure 4 It is a flow chart of an embodiment of pressure control in a preset first rate frequency reduction mode (such as a constant speed frequency limiting mode) in the method of the present invention;

[0034] Figure 5 It is a flow chart of an embodiment of pressure control in a preset block diagram control mode (such as a compressor block diagram control mode) in the method of the present invention;

[0035] Figure 6 It is a flow chart of an embodiment of pressure control in a preset second rate frequency reduction mode (such as a fast frequency reduction mode) in the method of the present invention;

[0036] Figure 7 It is a flow chart of an embodiment of pressure control in a preset third rate frequency reduction mode (such as a rapid frequency reduction mode) in the method of the present invention;

[0037] Figure 8 It is a flow chart of an embodiment of pressure control in a preset fourth rate frequency reduction mode (such as a flying frequency reduction mode) in the method of the present invention;

[0038] Fig. 9 It is a flow chart of an embodiment of pressure control in a preset high pressure protection mode in the method of the present invention;

[0039] Fig.10 It is a structural schematic diagram of an embodiment of a control device for a variable frequency heat pump unit of the present invention;

[0040] Fig.11 This is a schematic diagram of compressor frequency reduction pressure;

[0041] Fig.12 A flow chart of an embodiment of a control method for a variable frequency heat pump unit;

[0042] Fig.13 The present invention is a flow chart of another embodiment of a control method for a variable frequency heat pump unit.

[0043] In conjunction with the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows:

[0044] 102 - acquisition unit; 104 - control unit. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0046] Considering that fixed-frequency compressors are generally not equipped with pressure sensors, they only rely on the on and off of the high-pressure switch to control the high-pressure pressure. If the high-pressure pressure is high, the compressor will be disconnected and shut down, and if the high-pressure pressure is low, the compressor will be restarted. Variable-frequency compressors are basically equipped with high-pressure sensors. In addition to the high-pressure switch, they can also cooperate with the compressor block diagram to control the compressor operating range and ensure the reliability of the unit operation. In related schemes, a single high-pressure pressure point is generally used to limit and reduce the frequency of the compressor. The pressure range control of the variable-frequency heat pump unit is generally to limit the frequency of the unit by exceeding a certain high-pressure threshold to maintain the high-pressure level, but it is easy to cause the unit to frequently have high-pressure protection, affecting the reliable operation of the unit.

[0047] In addition, during the control process of the variable frequency heat pump unit, due to changes in the load on the evaporation or condensation side, or excessive adjustment of the coordinated control of the electronic expansion valve and the compressor frequency, it is easy to cause high pressure to exceed the range. The general variable frequency heat pump unit only has frequency limit, frequency reduction, and high pressure protection. There is no subdivision between frequency limit and high pressure protection. If the high pressure exceeds the frequency reduction pressure, the compressor frequency has reached the lower limit frequency, but has not reached the high pressure protection value, the unit will always maintain ultra-high pressure operation, or it can only wait until the pressure reaches the high pressure protection before shutting down.

[0048] Therefore, the scheme of the present invention proposes a control method for a variable frequency heat pump unit, which divides multiple frequency reduction spaces in detail in combination with the compressor block diagram and the high-voltage switch protection value, and adopts a seven-fold pressure control method of frequency limiting, normal speed frequency reduction, ultra-compressor block diagram, rapid frequency reduction, rapid frequency reduction, rapid frequency reduction, and high-voltage protection to control the high pressure within a reasonable range, avoid frequent ultra-high pressure operation and high-pressure protection of the unit, make the unit operate stably and reliably, and ensure that the unit operates within a safe range.

[0049] According to an embodiment of the present invention, a control method for a variable frequency heat pump unit is provided, such as Figure 1 The flow chart of an embodiment of the method of the present invention is shown in FIG. The variable frequency heat pump unit has a compressor; in the scheme of the present invention, as Figure 1As shown, the control method of the variable frequency heat pump unit includes: steps S110 to S140.

[0050] At step S110, the high pressure threshold of the compressor block diagram control (such as the high pressure P of the compressor block diagram) is obtained. 压缩机框图高压 ), and obtain the high pressure protection pressure threshold of the compressor (such as the high pressure protection high pressure P of the compressor). 高压保护 );Wherein, the block diagram control high pressure threshold of the compressor and the high pressure protection pressure threshold of the compressor can be pre-set according to the performance of the compressor.

[0051] At step S120, the high-pressure pressure range of the compressor is determined according to the high-pressure pressure threshold of the compressor block diagram control and the high-pressure protection pressure threshold of the compressor; wherein the high-pressure pressure range of the compressor includes: pressure intervals, and the number of the pressure intervals is more than two; corresponding to each of the more than two pressure intervals, there is a corresponding frequency reduction amplitude of the compressor and a residence time after the frequency is reduced according to the frequency reduction amplitude of the compressor.

[0052] At step S130, after the variable frequency heat pump unit is powered on and the compressor is turned on, the current high pressure pressure of the compressor is obtained according to a preset sampling period, specifically, the current exhaust pressure at the exhaust port of the compressor is obtained as the current high pressure pressure of the variable frequency heat pump unit, and the current frequency of the compressor is obtained.

[0053] At step S140, the current frequency of the compressor is controlled according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor to adjust the current high-pressure pressure of the compressor to within the high-pressure pressure range of the compressor, so that the variable frequency heat pump unit operates within the high-pressure pressure range of the compressor, thereby ensuring stable and reliable operation of the variable frequency heat pump unit.

[0054] The solution of the present invention proposes a control method for a variable frequency heat pump unit, setting a high-pressure range with more than two pressure intervals, such as dividing multiple frequency reduction spaces in detail in combination with the compressor block diagram and the high-pressure switch protection value, so as to control the high pressure within a reasonable range, avoid frequent ultra-high pressure operation and high-pressure protection of the unit, make the unit operate stably and reliably, and ensure that the unit operates within a safe range.

[0055] In some embodiments, the specific process of determining the high pressure range of the compressor by controlling the high pressure threshold and the high pressure protection pressure threshold of the compressor according to the block diagram of the compressor in step S120 is described in the following exemplary embodiment.

[0056] Combine the following Figure 2The flowchart of an embodiment of determining the high-pressure range of the compressor in the method of the present invention further illustrates the specific process of determining the high-pressure range of the compressor in step S120, including: steps S210 to S260.

[0057] Step S210, determining the difference between the block diagram control high pressure threshold of the compressor and the preset first pressure threshold as the frequency-limiting high pressure threshold of the compressor, such as the compressor frequency-limiting high pressure pressure P 高压限频＝ P 压缩机框图高压 -△P1. The preset first pressure threshold is △P1.

[0058] Step S220, the difference between the block diagram control high pressure threshold of the compressor and the preset second pressure threshold is determined as the first rate frequency reduction high pressure threshold of the compressor, such as the compressor constant speed frequency reduction high pressure threshold P 高压常速降频＝ P 压缩机框图高压 -△P2. The preset second pressure threshold is △P2.

[0059] Step S230, the sum of the block diagram control high pressure threshold of the compressor and the preset third pressure threshold is determined as the second rate frequency reduction high pressure pressure threshold of the compressor, such as the compressor rapid frequency reduction high pressure pressure P 高压快速降频＝ P 压缩机框图高压 +△P3. The preset third pressure threshold is △P3.

[0060] Step S240: The difference between the high-pressure protection pressure threshold of the compressor and the preset fourth pressure threshold is determined as the third rate frequency reduction high-pressure pressure threshold of the compressor, such as the compressor rapid frequency reduction high-pressure pressure P 高压急速降频＝ P 高压保护 -△P4. The preset fourth pressure threshold is △P4.

[0061] Step S250, the difference between the high pressure protection pressure threshold of the compressor and the preset fifth pressure threshold is used to determine the fourth rate frequency reduction high pressure pressure threshold of the compressor, such as the compressor rapid frequency reduction high pressure pressure P 高压飞速降频＝ P 高压保护 -△P5.

[0062] Step S260, determines the high pressure range of the compressor based on the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure threshold of the compressor, the fourth rate frequency reduction high pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. Among them, the high-pressure pressure range of the compressor includes: a pressure interval divided by the frequency-limited high-pressure pressure threshold of the compressor, the block diagram control high-pressure pressure threshold of the compressor, the first rate frequency reduction high-pressure pressure threshold of the compressor, the second rate frequency reduction high-pressure pressure threshold of the compressor, the third rate frequency reduction high-pressure pressure threshold of the compressor, the fourth rate frequency reduction high-pressure pressure threshold of the compressor, and the high-pressure protection pressure threshold of the compressor; that is, more than two of the pressure intervals are specifically divided by the frequency-limited high-pressure pressure threshold of the compressor, the block diagram control high-pressure pressure threshold of the compressor, the first rate frequency reduction high-pressure pressure threshold of the compressor, the second rate frequency reduction high-pressure pressure threshold of the compressor, the third rate frequency reduction high-pressure pressure threshold of the compressor, the fourth rate frequency reduction high-pressure pressure threshold of the compressor, and the high-pressure protection pressure threshold of the compressor.

[0063] In the solution of the present invention, it is defined as follows: the high pressure pressure of the unit monitored in real time by the high pressure sensor is P 高压压力 , compressor frequency limiting high pressure P 高压限频＝ P 压缩机框图高压 -△P1, compressor constant speed frequency reduction high pressure P 高压常速降频＝ P 压缩机框图高压 -△P2, compressor block diagram high pressure P 压缩机框图高压 , the compressor quickly reduces the frequency and high pressure P 高压快速降频＝ P 压缩机框图高压 +△P3, the compressor rapidly reduces the frequency and high pressure P 高压急速降频＝ P 高压保护 -△P4, the compressor rapidly reduces the frequency and high pressure P 高压飞速降频＝ P 高压保护 -△P5, compressor high pressure protection high pressure P 高压保护 Among them, the values ​​of △P1, △P2, △P3, △P4, and △P5 are all greater than 0, and must satisfy: the above calculation results can comply with this principle, and the high pressure relationship is P 高压限频 <P 高压常速降频 <P 压缩机框图高压 <P 高压快速降频 <P 高压急速降频 <P 高压飞速降频 <P 高压保护 , and P 压缩机框图高压 (compressor characteristics) and P高压保护 (High pressure switch value) These two are reference benchmarks and can be set according to the maximum operating pressure of each.

[0064] Fig.11 This is a schematic diagram of compressor frequency reduction pressure. Fig.11 As shown, the high pressure relationship is P 高压限频 <P 高压常速降频 <P 压缩机框图高压 <P 高压快速降频 <P 高压急速降频 <P 高压飞速降频 <P 高压保护 The pressure varies according to the type of refrigerant. For example, if it is R32 refrigerant, the pressure is P 高压限频 (4300kpa)<P 高压常速降频 (4350kpa)<P 压缩机框图高压 (4400kpa)<P 高压快速降频 (4450kpa)<P 高压急速降频 (4500kpa)<P 高压飞速降频 (4600kpa)<P 高压保护 (4700kpa).

[0065] In related schemes, variable frequency heat pump units generally limit the frequency reduction of the unit by exceeding a certain high pressure value to maintain the high pressure level, but this method is relatively simple. In the scheme of the present invention, a seven-fold pressure control method of frequency limiting, constant speed frequency reduction, super compressor block diagram, fast frequency reduction, rapid frequency reduction, rapid frequency reduction, and high pressure protection is adopted to control the high pressure within a reasonable range, avoid frequent ultra-high pressure operation and high pressure protection of the unit, and make the unit operate stably and reliably.

[0066] Fig.12 is a flow chart of an embodiment of a control method for a variable frequency heat pump unit, Fig.13 FIG. 2 is a flow chart of another embodiment of a control method for a variable frequency heat pump unit. Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit includes: step 1, after the compressor is turned on, the high pressure sensor and high pressure switch of the unit detect the high pressure pressure, and then selectively execute at least one of step 2, step 3, step 4, step 5, step 6, step 7, and step 8 according to the actual situation. Among them, the high pressure pressure is the pressure at the exhaust port of the compressor, the high pressure sensor and the high pressure switch are respectively used to detect the high pressure pressure, and the high pressure sensor can detect the specific pressure value in real time; the high pressure switch is only a switch that plays an on-off role, that is, when the high pressure pressure is greater than the high pressure protection value, the high pressure switch will be disconnected, and when the high pressure pressure is lower than a certain pressure, the high pressure switch will resume closing.

[0067] In the scheme of the present invention, multiple frequency reduction spaces are divided in detail in combination with the compressor block diagram and the high-voltage switch protection value, and a seven-fold pressure control method of frequency limiting, normal speed frequency reduction, ultra-compressor block diagram, fast frequency reduction, rapid frequency reduction, rapid frequency reduction and high-voltage protection is adopted. Different frequency reduction amplitudes and residence times are used according to each divided pressure interval to control the high pressure within a reasonable range, avoid frequent ultra-high pressure operation and high pressure protection of the unit, make the unit operate stably and reliably, and ensure that the unit operates within a safe range.

[0068] In the related schemes, compressor frequency modulation, electronic expansion valve action, changes in operating conditions on the evaporation and condensation sides, extreme operating conditions such as low temperature and high humidity, high temperature and high humidity, and maximum operating temperature may cause the high pressure to exceed the expected range, or even high pressure protection. Generally, the pressure is controlled within the high pressure protection -△P range, leaving a margin to prevent frequent high pressure protection of the unit. In order to accurately control the high pressure range, the scheme of the present invention combines the compressor block diagram and the high-voltage switch characteristics, and proposes a seven-layer pressure control method. According to different pressure judgments, the frequency is limited in advance, and the frequency is reduced in stages. There is a buffer judgment time for the frequency reduction, which solves the problem of too much and too fast frequency reduction causing system instability and high pressure protection caused by excessive high pressure rushing. At the same time, it avoids the problem of frequent wear of the compressor due to over-compressor block diagram, ensuring stable operation of the unit.

[0069] In the scheme of the present invention, a seven-fold pressure control method of frequency limiting, constant speed frequency reduction, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, rapid frequency reduction, and high-pressure protection is adopted to control the pressure within a reasonable range to avoid frequent ultra-high pressure operation and high-pressure protection of the unit. In order to determine the rationality of the set pressure value of the frequency reduction limit, it is necessary to comprehensively determine each pressure value through the compressor operation block diagram and the high-pressure switch protection value. Different frequency reduction amplitudes and dwell times are used according to the pressure of each divided interval to ensure non-ultra-high pressure operation and non-frequent high-pressure protection, so that the unit can operate stably and reliably.

[0070] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the compressor frequency limiting high pressure pressure threshold, the compressor block diagram control high pressure pressure threshold, the compressor first rate frequency reduction high pressure pressure threshold, the compressor second rate frequency reduction high pressure pressure threshold, the compressor third rate frequency reduction high pressure pressure threshold, the compressor fourth rate frequency reduction high pressure pressure threshold, and the compressor high pressure protection pressure threshold. In step S140, the current frequency of the compressor is controlled according to the current high pressure of the compressor and the high pressure range of the compressor, including: a process of pressure control under a preset frequency limiting mode (such as a high pressure frequency limiting mode).

[0071] Combine the following Figure 3The flowchart of an embodiment of pressure control under a preset frequency limiting mode (such as a high-voltage frequency limiting mode) in the method of the present invention is shown, which further illustrates the specific process of pressure control under a preset frequency limiting mode (such as a high-voltage frequency limiting mode) in step S140, including: step S310 to step S340.

[0072] Step S310, after the compressor is started, it is determined whether the current high pressure of the compressor is detected to be greater than or equal to the frequency-limited high pressure pressure threshold of the compressor and less than the first rate frequency reduction high pressure pressure threshold of the compressor continuously within the first set time in the preset frequency-limited mode. The first set time in the preset frequency-limited mode, such as t 连续1 time.

[0073] Step S320: If it is determined that the current high pressure pressure of the compressor is greater than or equal to the frequency-limiting high pressure pressure threshold of the compressor and less than the first rate frequency reduction high pressure pressure threshold of the compressor continuously detected within the first set time under the preset frequency-limiting mode, the compressor is controlled to enter the preset frequency-limiting mode to limit the increase of the current frequency of the compressor; then it is determined whether the current high pressure pressure of the compressor is less than the frequency-limiting high pressure pressure threshold of the compressor continuously detected within the second set time under the preset frequency-limiting mode; of course, if it is determined that the current high pressure pressure of the compressor is not greater than or equal to the frequency-limiting high pressure pressure threshold of the compressor and less than the first rate frequency reduction high pressure pressure threshold of the compressor continuously detected within the first set time under the preset frequency-limiting mode, the compressor is controlled to maintain the current operation, and returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure range of the compressor. Among them, the preset second set time under the frequency-limiting mode, such as t 连续2 time.

[0074] Step S330: If it is determined that the current high pressure of the compressor is less than the frequency-limiting high pressure threshold of the compressor continuously within the second setting time in the preset frequency-limiting mode, then after maintaining the current frequency of the compressor for the third setting time in the preset frequency-limiting mode, the compressor is controlled to exit the preset frequency-limiting mode to exit the restriction on the increase of the current frequency of the compressor and resume the control of the increase and decrease of the current frequency of the compressor. The third setting time in the preset frequency-limiting mode, such as t 连续3 time.

[0075] Step S340, if it is determined that the current high-pressure pressure of the compressor is not continuously detected to be less than the frequency-limiting high-pressure pressure threshold of the compressor within the second set time under the preset frequency-limiting mode, then return to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor.

[0076] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 2, frequency limiting pressure control method. Frequency limiting: When the high pressure reaches a certain value, the compressor is not allowed to increase the frequency. At this time, it is necessary to maintain the current frequency to limit the increase of the compressor frequency; the compressor frequency limiting high pressure pressure P 高压限频＝ P 压缩机框图高压 -△P1.

[0077] In step 2, after the compressor starts, if the continuous t 连续1 Time detected P 高压限频 ≤P 高压压力 <P 高压常速降频 , the compressor current frequency limit rises. If continuous t 连续2 Time detected P 高压压力 <P 高压限频 , maintain the current frequency F 当前 Continuous 连续3 After a certain time, the frequency limit is exited and the normal control pressure is restored without limit.

[0078] In the solution of the present invention, through frequency-limited pressure control, the high-pressure pressure reaches a certain value, and the compressor is not allowed to increase the frequency any further. At this time, it is necessary to maintain the current frequency to limit the increase in the compressor frequency, and limit the current frequency in advance to avoid excessive high pressure, thereby reducing frequent start-up and shutdown and high-pressure protection.

[0079] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the compressor frequency limiting high pressure pressure threshold, the compressor block diagram control high pressure pressure threshold, the compressor first rate frequency reduction high pressure pressure threshold, the compressor second rate frequency reduction high pressure pressure threshold, the compressor third rate frequency reduction high pressure pressure threshold, the compressor fourth rate frequency reduction high pressure pressure threshold, and the compressor high pressure protection pressure threshold. In step S140, the current frequency of the compressor is controlled according to the current high pressure of the compressor and the high pressure pressure range of the compressor, and also includes: a process of pressure control under a preset first rate frequency reduction mode (such as a normal speed frequency limiting mode).

[0080] Combine the following Figure 4The flowchart of an embodiment of pressure control under a preset first rate frequency reduction mode (such as a normal speed frequency limiting mode) in the method of the present invention is shown, which further illustrates the specific process of pressure control under a preset first rate frequency reduction mode (such as a normal speed frequency limiting mode) in step S140, including: steps S410 to S450.

[0081] Step S410, after the compressor is started, it is determined whether the current high pressure of the compressor is detected to be greater than or equal to the first rate frequency reduction high pressure pressure threshold of the compressor and less than the block diagram control high pressure pressure threshold of the compressor continuously within the first set time in the preset first rate frequency reduction mode. The first set time in the preset first rate frequency reduction mode, such as t 连续1 time.

[0082] Step S420, if it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and less than the block diagram control high-pressure pressure threshold of the compressor continuously within the first set time in the preset first rate frequency reduction mode, then the compressor is controlled to enter the preset first rate frequency reduction mode to control the current frequency of the compressor to reduce the preset first rate frequency reduction value; then it is re-determined whether it is detected that the current high-pressure pressure of the compressor is greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and less than the block diagram control high-pressure pressure threshold of the compressor continuously within the first set time in the preset first rate frequency reduction mode: if so, the compressor is controlled The current frequency is reduced by the preset first rate frequency reduction value at intervals of the preset first rate frequency reduction time; otherwise, the current frequency of the compressor is controlled again based on the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the first rate frequency reduction high pressure pressure threshold of the compressor and less than the first rate frequency reduction high pressure pressure threshold of the compressor within the first set time under the preset first rate frequency reduction mode, the compressor is controlled to maintain the current operation, and the current frequency of the compressor is controlled again based on the current high pressure pressure of the compressor and the high pressure pressure range of the compressor.

[0083] Step S430, after controlling the current frequency of the compressor to reduce the preset first rate frequency reduction value every preset first rate frequency reduction time, determine whether the current high pressure pressure of the compressor is detected to be less than the first rate frequency reduction high pressure pressure threshold of the compressor continuously within the second set time in the preset first rate frequency reduction mode. The second set time in the preset first rate frequency reduction mode, such as t 连续2 The preset first rate frequency reduction time is t降频时间 , the preset first rate frequency reduction value is such as △F 常速降频 .

[0084] Step S440: If it is determined that the current high pressure pressure of the compressor is less than the first rate frequency reduction high pressure pressure threshold of the compressor continuously within the second set time in the preset first rate frequency reduction mode, then after maintaining the current frequency of the compressor in the preset first rate frequency reduction mode for the third set time, the compressor is controlled to exit the preset first rate frequency reduction mode, so as to exit the current frequency reduction of the compressor controlled in the preset first rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high pressure of the compressor and the high pressure range of the compressor. The third set time in the preset first rate frequency reduction mode, such as t in the first rate frequency reduction mode, is preferably set to t in the first rate frequency reduction mode. 连续3 time.

[0085] Step S450, if it is determined that the current high-pressure pressure of the compressor is not continuously detected to be less than the first-rate frequency reduction high-pressure pressure threshold of the compressor within the second set time of the preset first-rate frequency reduction mode, then return to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor.

[0086] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 3, a pressure control method of constant speed frequency reduction. Constant speed frequency reduction: When the high pressure exceeds the frequency limit pressure and reaches the pressure of constant speed frequency reduction, the compressor is not allowed to increase the frequency and must reduce the frequency at a certain speed to prevent the pressure from rising. Since there is still space between the high pressure and the boundary, only a small frequency △F needs to be reduced. 常速降频 ; Compressor normal speed frequency reduction high pressure P 高压常速降频＝ P 压缩机框图高压 -△P2.

[0087] In step 3, after the compressor starts, if the continuous t 连续1 Time detected P 高压常速降频 ≤P 高压压力 <P 压缩机框图高压 , when the condition is met for the first time, the frequency is immediately reduced △F 常速降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 常速降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 高压常速降频 , maintain the current frequency F 当前 Continuous 连续3After a certain time, exit the normal speed frequency reduction, and determine whether to resume normal control or enter frequency limit control according to the real-time monitoring pressure.

[0088] In the scheme of the present invention, through the pressure control of constant speed frequency reduction, the high pressure exceeds the frequency limit pressure and reaches the pressure of constant speed frequency reduction, the compressor is not allowed to increase the frequency and must reduce the frequency at a certain speed to prevent the pressure from rising. Since there is still room for the high pressure to reach the boundary, only a small frequency △F needs to be reduced. 常速降频 ; The frequency reduction is small and the unit reliability is high.

[0089] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. In step S140, the current frequency of the compressor is controlled according to the current high pressure of the compressor and the high pressure range of the compressor, and the process of pressure control under a preset block diagram control mode (such as a compressor block diagram control mode).

[0090] Combine the following Figure 5 The flowchart of an embodiment of pressure control under a preset block diagram control mode (such as a compressor block diagram control mode) in the method of the present invention is shown, which further illustrates the specific process of pressure control under a preset block diagram control mode (such as a compressor block diagram control mode) in step S140, including: steps S510 to S550.

[0091] Step S510, after the compressor is started, it is determined whether the current high pressure of the compressor is detected to be greater than or equal to the high pressure threshold of the block diagram control of the compressor and less than the second rate reduction high pressure threshold of the compressor within the first set time under the preset block diagram control mode. The first set time under the preset block diagram control mode is, for example, t 连续1 time.

[0092] Step S520, if it is determined that the current high-pressure pressure of the compressor is greater than or equal to the block diagram control high-pressure pressure threshold of the compressor and less than the second rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time under the preset block diagram control mode, then the compressor is controlled to enter the preset block diagram control mode to control the current frequency of the compressor to reduce the preset block diagram control frequency reduction value; then it is re-determined whether it is continuously detected within the first set time under the preset block diagram control mode that the current high-pressure pressure of the compressor is greater than or equal to the block diagram control high-pressure pressure threshold of the compressor and less than the second rate frequency reduction high-pressure pressure threshold of the compressor: if so, the compressor is controlled The current frequency of the compressor is reduced by the preset block diagram control frequency reduction value at every preset block diagram control time; otherwise, the control returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the block diagram control high pressure pressure threshold of the compressor and less than the block diagram control high pressure pressure threshold of the compressor within the first set time under the preset block diagram control mode, the compressor is controlled to maintain the current operation, and returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor.

[0093] Step S530, after controlling the current frequency of the compressor to reduce the preset block diagram control frequency reduction value at every preset block diagram control time, determine whether it is continuously detected that the current high pressure pressure of the compressor is less than the block diagram control high pressure pressure threshold of the compressor within the second set time under the preset block diagram control mode. The second set time under the preset block diagram control mode, such as t 连续2 Time. The preset block diagram control time is t 降频时间 , the preset block diagram controls the frequency reduction value such as △F 常速降频 .

[0094] Step S540: If it is determined that the current high pressure pressure of the compressor is less than the high pressure pressure threshold of the block diagram control of the compressor continuously within the second set time under the preset block diagram control mode, then after maintaining the current frequency of the compressor for the third set time under the preset block diagram control mode, the compressor is controlled to exit the preset block diagram control mode to exit the current frequency reduction of the compressor controlled by the preset block diagram control mode, and then the current frequency of the compressor is controlled again according to the current high pressure of the compressor and the high pressure range of the compressor. The third set time under the preset block diagram control mode is, for example, t 连续3 time.

[0095] Step S550: If it is determined that the current high pressure of the compressor is not detected to be less than the block diagram control high pressure pressure threshold of the compressor within the second set time under the preset block diagram control mode, and it is determined that the current high pressure of the compressor is not detected to be less than the block diagram control high pressure pressure threshold of the compressor within the continuous control time under the preset block diagram control mode, then the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop. Among them, the continuous control under the preset block diagram control mode, such as t 压缩机框图持续 .

[0096] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 4, the pressure control method of the compressor block diagram. Super compressor block diagram: The high pressure has reached the limit of the range allowed for the compressor to operate. In order to ensure the reliability of the unit, a pressure margin is reserved and to prevent the high pressure from continuing to rise, the unit reduces △F 超框图降频 Frequency; High pressure compressor block diagram High pressure P 压缩机框图高压 .

[0097] In step 4, after the compressor starts, if the continuous t 连续1 Time detected P 压缩机框图高压 ≤P 高压压力 <P 高压快速降频 , when the condition is met for the first time, the frequency is immediately reduced △F 超框图降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 超框图降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 压缩机框图高压 , maintain the current frequency F 当前 Continuous 连续3 After a certain time, the compressor block diagram control is exited, and the real-time monitoring pressure is used to determine whether to resume normal control or enter other pressure limit frequency reduction control; if continuous t 压缩机框图持续 If the high pressure still does not exit the compressor block diagram control during the operating time, the unit will shut down.

[0098] In the scheme of the present invention, through the pressure control of the compressor block diagram, the high pressure has reached the limit of the range allowed for the compressor to operate. In order to ensure the reliability of the unit, a pressure margin is reserved and to prevent the high pressure from continuing to rise, the unit reduces △F 超框图降频 The frequency is buffered; if the high pressure continues to rise for a certain period of time, the unit's super compressor block diagram will shut down.

[0099] In the related schemes, the electronic expansion valve and the compressor frequency are adjusted at the same time, and the external working conditions change in real time. If the coordination and control are not good, the high pressure of the unit is likely to exceed the range; that is, when the electronic expansion valve or the compressor frequency of the unit is adjusted too much, it is easy to cause the high pressure to exceed the range. In the scheme of the present invention, before the high pressure exceeds the range, the adjustment space margin is reserved to prevent the unit from running to high pressure protection every time, or reducing the frequency too quickly; in this way, the scheme of the present invention adopts the seven-level pressure control method to reduce the risk of over-adjustment of the unit and ensure the reliable operation of the unit.

[0100] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. In step S140, the current frequency of the compressor is controlled according to the current high pressure of the compressor and the high pressure range of the compressor, and the process of pressure control under the preset second rate frequency reduction mode (such as fast frequency reduction mode) is also included.

[0101] Combine the following Figure 6 The flowchart of an embodiment of pressure control in a preset second rate frequency reduction mode (such as a fast frequency reduction mode) in the method of the present invention is shown, which further illustrates the specific process of pressure control in a preset second rate frequency reduction mode (such as a fast frequency reduction mode) in step S140, including: steps S610 to S650.

[0102] Step S610, after the compressor is started, it is determined whether the current high pressure of the compressor is detected to be greater than or equal to the second rate frequency reduction high pressure pressure threshold of the compressor and less than the third rate frequency reduction high pressure pressure threshold of the compressor within the first set time in the preset second rate frequency reduction mode. The first set time in the preset second rate frequency reduction mode, such as t 连续1 time.

[0103] Step S620: If it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the second rate frequency reduction high-pressure pressure threshold of the compressor and less than the third rate frequency reduction high-pressure pressure threshold of the compressor within the first set time continuously under the preset second rate frequency reduction mode, then the compressor is controlled to enter the preset second rate frequency reduction mode to control the current frequency of the compressor to reduce the preset second rate frequency reduction value; then it is re-determined whether it is detected that the current high-pressure pressure of the compressor is greater than or equal to the second rate frequency reduction high-pressure pressure threshold of the compressor and less than the third rate frequency reduction high-pressure pressure threshold of the compressor within the first set time continuously under the preset second rate frequency reduction mode: if so, the compressor is controlled to enter the preset second rate frequency reduction mode to control the current frequency of the compressor to reduce the preset second rate frequency reduction value; The current frequency of the machine is reduced by a preset second rate frequency reduction value at intervals of a preset second rate frequency reduction time; otherwise, the control returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the second rate frequency reduction high pressure pressure threshold of the compressor and less than the second rate frequency reduction high pressure pressure threshold of the compressor within the first set time under the preset second rate frequency reduction mode, the compressor is controlled to maintain the current operation, and the control returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor.

[0104] Step S630, after controlling the current frequency of the compressor to reduce the preset second rate frequency reduction value every preset second rate frequency reduction time, determine whether the current high pressure pressure of the compressor is continuously detected to be less than the second rate frequency reduction high pressure pressure threshold of the compressor within the second set time in the preset second rate frequency reduction mode. The second set time in the preset second rate frequency reduction mode, such as t 连续2 The preset second rate frequency reduction time is t 降频时间 The preset second rate reduction value is △F 常速降频 .

[0105] Step S640: If it is determined that the current high pressure pressure of the compressor is less than the second rate frequency reduction high pressure pressure threshold of the compressor continuously within the second set time in the preset second rate frequency reduction mode, then after maintaining the current frequency of the compressor for the third set time in the preset second rate frequency reduction mode, the compressor is controlled to exit the preset second rate frequency reduction mode, so as to exit the current frequency reduction of the compressor controlled according to the preset second rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high pressure of the compressor and the high pressure range of the compressor. The third set time in the preset second rate frequency reduction mode, such as t in the second rate frequency reduction mode, is preferably t连续3 time.

[0106] Step S650: If it is determined that the current high pressure pressure of the compressor is not detected to be less than the second rate frequency reduction high pressure pressure threshold of the compressor within the second set time in the preset second rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not detected to be less than the second rate frequency reduction high pressure pressure threshold of the compressor within the preset continuous control time in the second rate frequency reduction mode, then the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop. The continuous control in the preset second rate frequency reduction mode, such as t 快速降频持续 .

[0107] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 5, a pressure control method for rapid frequency reduction. Rapid frequency reduction: The high pressure has exceeded the compressor block diagram range limit, but the excess is not much, to prevent further exceeding the range, and to allow the pressure to quickly return to the compressor block diagram range, the unit frequency reduction range is increased to reduce △F 快速降频 ; Compressor rapid frequency reduction high pressure P 高压快速降频＝ P 压缩机框图高压 +△P3.

[0108] In step 5, after the compressor starts, if the continuous t 连续1 Time detected P 高压快速降频 ≤P 高压压力 <P 高压急速降频 , when the condition is met for the first time, the frequency is immediately reduced △F 快速降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 快速降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 高压快速降频 , maintain the current frequency F 当前 Continuous 连续3 After a certain time, the system exits the rapid frequency reduction control and determines whether to resume normal control or enter other pressure-limited frequency reduction control according to the real-time monitoring pressure. 快速降频持续 If the high voltage still does not exit the rapid frequency reduction control during the operating time, the unit will shut down.

[0109] In the scheme of the present invention, through the pressure control of rapid frequency reduction, the high pressure has exceeded the compressor block diagram range limit, but the excess is not much, to prevent further exceeding the range, and to make the pressure quickly return to the compressor block diagram range, the unit frequency reduction amplitude is increased to reduce △F 快速降频 If the high pressure continues to rise for a certain period of time, the unit's super compressor block diagram will shut down.

[0110] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. In step S140, the current frequency of the compressor is controlled according to the current high pressure of the compressor and the high pressure pressure range of the compressor, and the process of pressure control under the preset third rate frequency reduction mode (such as rapid frequency reduction mode) is also included.

[0111] Combine the following Figure 7 The flowchart of an embodiment of pressure control under a preset third rate frequency reduction mode (such as a rapid frequency reduction mode) in the method of the present invention is shown, which further illustrates the specific process of pressure control under a preset third rate frequency reduction mode (such as a rapid frequency reduction mode) in step S140, including: steps S710 to S750.

[0112] Step S710, after the compressor is started, it is determined whether the current high pressure of the compressor is detected to be greater than or equal to the third rate frequency reduction high pressure pressure threshold of the compressor and less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the first set time in the third rate frequency reduction mode. The first set time in the third rate frequency reduction mode is, for example, t 连续1 time.

[0113] Step S720: If it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the third rate frequency reduction high-pressure pressure threshold of the compressor and less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time under the preset third rate frequency reduction mode, then the compressor is controlled to enter the preset third rate frequency reduction mode to control the current frequency of the compressor to reduce the preset third rate frequency reduction value; then it is re-determined whether it is detected that the current high-pressure pressure of the compressor is greater than or equal to the third rate frequency reduction high-pressure pressure threshold of the compressor and less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time under the preset third rate frequency reduction mode: if so, the compressor is controlled to enter the preset third rate frequency reduction mode to control the current frequency of the compressor to reduce the preset third rate frequency reduction value; The current frequency of the machine is reduced by a preset third rate frequency reduction value at every preset third rate frequency reduction time; otherwise, the control returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the third rate frequency reduction high pressure pressure threshold of the compressor and less than the third rate frequency reduction high pressure pressure threshold of the compressor within the first set time in the preset third rate frequency reduction mode, the compressor is controlled to maintain the current operation, and the control returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor.

[0114] Step S730, after controlling the current frequency of the compressor to decrease by the preset third rate frequency reduction value every preset third rate frequency reduction time, determine whether the current high pressure pressure of the compressor is detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor continuously within the third setting time in the preset third rate frequency reduction mode. The third setting time in the preset third rate frequency reduction mode, such as t in the third rate frequency reduction mode, is continuously detected within the third setting time in the preset third rate frequency reduction mode. 连续2 The preset third rate frequency reduction time is t 降频时间 The preset third rate frequency reduction value is △F 常速降频 .

[0115] Step S740: If it is determined that the current high pressure pressure of the compressor is less than the third rate frequency reduction high pressure pressure threshold of the compressor continuously within the third set time in the preset third rate frequency reduction mode, then after maintaining the current frequency of the compressor for the fourth time in the preset third rate frequency reduction mode, the compressor is controlled to exit the preset third rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset third rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high pressure of the compressor and the high pressure range of the compressor. The fourth time in the preset third rate frequency reduction mode, such as t in the third rate frequency reduction mode, is连续3 time.

[0116] Step S750: If it is determined that the current high pressure pressure of the compressor is not detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the third set time in the preset third rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the preset continuous control time in the third rate frequency reduction mode, then the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop. The continuous control in the preset third rate frequency reduction mode, such as t 急速降频持续 .

[0117] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 6, a pressure control method for rapid frequency reduction. Rapid frequency reduction: the high pressure has exceeded the compressor block diagram range limit by a certain pressure, to prevent further exceeding the range, the unit immediately increases the frequency reduction range △F 急速降频 ; The compressor rapidly reduces the frequency and high pressure P 高压急速降频＝ P 高压保护 -△P4.

[0118] In step 6, after the compressor starts, if the continuous 连续1 Time detected P 高压急速降频 ≤P 高压压力 <P 高压飞速降频 , when the condition is met for the first time, the frequency is immediately reduced △F 急速降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 急速降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 高压急速降频 , maintain the current frequency F 当前 Continuous 连续3 After a certain time, the system will exit the rapid frequency reduction control and determine whether to resume normal control or enter other pressure-limited frequency reduction control according to the real-time monitoring pressure. 急速降频持续 If the high voltage still does not exit the rapid frequency reduction control during the operating time, the unit will shut down.

[0119] In the scheme of the present invention, through the pressure control of rapid frequency reduction, the high pressure has exceeded the compressor block diagram range limit by a certain pressure, to prevent further exceeding the range, the unit immediately increases the frequency reduction amplitude △F 急速降频 Let the pressure return to the compressor block diagram range quickly. If the high pressure continues to rise for a certain period of time, the unit will shut down.

[0120] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. In step S140, the current frequency of the compressor is controlled according to the current high pressure of the compressor and the high pressure range of the compressor, and the process of pressure control under the preset fourth rate frequency reduction mode (such as the rapid frequency reduction mode) is also included.

[0121] Combine the following Figure 8 The flowchart of an embodiment of pressure control in a preset fourth rate frequency reduction mode (such as a rapid frequency reduction mode) in the method of the present invention is shown, which further illustrates the specific process of pressure control in a preset fourth rate frequency reduction mode (such as a rapid frequency reduction mode) in step S140, including: steps S810 to S850.

[0122] Step S810, after the compressor is started, it is determined whether the current high pressure of the compressor is detected to be greater than or equal to the fourth rate frequency reduction high pressure pressure threshold of the compressor and less than the high pressure protection high pressure pressure threshold of the compressor within the first set time in the fourth rate frequency reduction mode. The first set time in the fourth rate frequency reduction mode is, for example, t 连续1 time.

[0123] Step S820, if it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the fourth-rate frequency reduction high-pressure pressure threshold of the compressor and less than the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time of the preset fourth-rate frequency reduction mode, then the compressor is controlled to enter the preset fourth-rate frequency reduction mode to control the current frequency of the compressor to reduce the preset fourth-rate frequency reduction value; then it is re-determined whether it is detected that the current high-pressure pressure of the compressor is greater than or equal to the fourth-rate frequency reduction high-pressure pressure threshold of the compressor and less than the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time of the preset fourth-rate frequency reduction mode: if so, the compressor is controlled The current frequency is reduced by the preset fourth rate frequency reduction value at every preset fourth rate frequency reduction time; otherwise, the control returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the fourth rate frequency reduction high pressure pressure threshold of the compressor and less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the first set time in the preset fourth rate frequency reduction mode, the compressor is controlled to maintain the current operation, and the control returns to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor.

[0124] Step S830, after controlling the current frequency of the compressor to decrease by the preset fourth rate frequency reduction value every preset fourth rate frequency reduction time, determine whether it is continuously detected that the current high pressure pressure of the compressor is less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the fourth time in the preset fourth rate frequency reduction mode. The fourth time in the preset fourth rate frequency reduction mode, such as t in the fourth rate frequency reduction mode, is continuously detected within the fourth time in the preset fourth rate frequency reduction mode. 连续2 The preset fourth rate frequency reduction time is t 降频时间 The preset fourth rate frequency reduction value is △F 常速降频 .

[0125] Step S840: If it is determined that the current high pressure pressure of the compressor is less than the fourth rate frequency reduction high pressure pressure threshold of the compressor continuously within the fourth time in the preset fourth rate frequency reduction mode, then after maintaining the current frequency of the compressor for the fourth time in the preset fourth rate frequency reduction mode, the compressor is controlled to exit the preset fourth rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset fourth rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high pressure of the compressor and the high pressure range of the compressor. The fourth time in the preset fourth rate frequency reduction mode, such as t in the fourth rate frequency reduction mode, is 连续3 time.

[0126] Step S850: If it is determined that the current high pressure pressure of the compressor is not detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the fourth time period of the preset fourth rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the continuous control time of the preset fourth rate frequency reduction mode, then the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop. The continuous control in the preset fourth rate frequency reduction mode is as follows: 飞速降频持续 .

[0127] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 7, a pressure control method of rapid frequency reduction. Rapid frequency reduction: When the high pressure is about to reach the high pressure protection value, it is necessary to quickly reduce △F 飞速降频 ; The compressor rapidly reduces the frequency and high pressure P 高压飞速降频＝ P 高压保护 -△P5.

[0128] In step 7, after the compressor starts, if the continuous 连续1 Time detected P 高压飞速降频 ≤P 高压压力 <P 高压保护 , when the condition is met for the first time, the frequency is immediately reduced △F 飞速降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 飞速降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 高压飞速降频 , maintain the current frequency F 当前 Continuous 连续3 After a certain time, the system will exit the rapid frequency reduction control and determine whether to resume normal control or enter other pressure limit frequency reduction control according to the real-time monitoring pressure. 飞速降频持续 If the high voltage still does not exit the rapid frequency reduction control during the operating time, the unit will shut down.

[0129] Among them, the frequency reduction relationship is △F 常速降频 <△F 超框图降频 <△F 快速降频 <△F 急速降频 <△F 飞速降频 For example: △F 常速降频 (2Hz)<△F 超框图降频 (4Hz)<△F 快速降频 (8Hz)<△F 急速降频 (10Hz)<△F 飞速降频 (12Hz).

[0130] The continuous running time and shutdown relationship is t 压缩机框图持续 >t 快速降频持续 >t 急速降频持续 >t 飞速降频持续 For example: 压缩机框图持续 (30min)>t 快速降频持续 (15min)>t 急速降频持续 (5min)>t 飞速降频持续 (3min).

[0131] In the solution of the present invention, through the rapid frequency reduction pressure control, the high pressure is about to reach the high pressure protection value, and it is necessary to quickly reduce △F 飞速降频 See if the high pressure can be unloaded. If the high pressure continues to rise for a certain period of time, the unit will shut down.

[0132] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. In step S140, the current frequency of the compressor is controlled according to the current high pressure of the compressor and the high pressure range of the compressor, and the process of pressure control under the preset high pressure protection mode is also included.

[0133] Combine the following Fig. 9 The flowchart of an embodiment of the pressure control in the preset high-pressure protection mode in the method of the present invention further illustrates the specific process of the pressure control in the preset high-pressure protection mode in step S140, including: step S910 to step S920.

[0134] Step S910, after the compressor is started, it is determined whether the current high pressure of the compressor is detected to be greater than or equal to the high pressure protection high pressure threshold of the compressor continuously within the first set time in the preset high pressure protection mode. The first set time in the preset fourth rate reduction mode, such as t 连续1 time.

[0135] Step S920, if it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the high-pressure protection high-pressure threshold of the compressor continuously within the first set time under the preset high-pressure protection mode, the high-pressure switch of the variable frequency heat pump unit is controlled to be disconnected, and the variable frequency heat pump unit is controlled to be shut down; of course, if it is determined that the current high-pressure pressure of the compressor is not detected to be greater than or equal to the high-pressure protection high-pressure threshold of the compressor continuously within the first set time under the preset high-pressure protection mode, the compressor is controlled to maintain the current operation, and returns to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor.

[0136] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 8, a pressure control method for high pressure protection. High pressure protection: when the high pressure exceeds the protection value of the high pressure switch, the unit will shut down due to a fault; the high pressure protection pressure P of the compressor 高压保护 .

[0137] In step 8, after the compressor starts, if the continuous 连续1 Time detected P 高压压力 ≥P 高压保护 , the high-voltage switch is disconnected and the unit shuts down.

[0138] In the solution of the present invention, through the pressure control of high-pressure protection, if the high-pressure exceeds the protection value of the high-pressure switch, the unit will fail and shut down.

[0139] In the scheme of the present invention, a seven-fold pressure control method is proposed, including frequency limiting, constant speed frequency reduction, super compressor block diagram, fast frequency reduction, rapid frequency reduction, rapid frequency reduction, and high-pressure protection. Different frequency reduction amplitudes and dwell times are used according to each divided pressure interval to control the high pressure within a reasonable range. Thus, the problem of excessive high pressure range caused by over-adjustment of the electronic expansion valve or compressor frequency is solved, and frequent ultra-high pressure operation and high-pressure protection of the unit are avoided, so that the unit can operate stably and reliably.

[0140] By adopting the technical solution of this embodiment, the pressure intervals corresponding to the seven-fold pressure control of frequency limiting, constant speed frequency reduction, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, extremely rapid frequency reduction and high-pressure protection are pre-set for the variable frequency heat pump unit, and different compressor frequency reduction amplitudes and residence times are set for each pressure interval; after the compressor of the variable frequency heat pump unit is turned on, the high-pressure pressure of the compressor is obtained, and according to the pressure interval to which the high-pressure pressure of the compressor belongs, the compressor is subjected to at least one of frequency limiting, constant speed frequency reduction, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, extremely rapid frequency reduction and high-pressure protection, so as to control the high-pressure pressure of the compressor within the set reasonable pressure range; thereby, the high-pressure pressure of the compressor is controlled within the set reasonable pressure range by performing at least one of frequency limiting, constant speed frequency reduction, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, extremely rapid frequency reduction and high-pressure protection on the compressor, thereby improving the reliability and safety of the unit operation.

[0141] According to an embodiment of the present invention, a control device for a variable frequency heat pump unit corresponding to the control method for the variable frequency heat pump unit is also provided. Fig.10 The structure diagram of an embodiment of the device of the present invention is shown in FIG. The variable frequency heat pump unit has a compressor; in the solution of the present invention, as Fig.10 As shown, the control device of the variable frequency heat pump unit includes: an acquisition unit 102 and a control unit 104.

[0142] The acquisition unit 102 is configured to acquire the high pressure threshold of the compressor block diagram control (such as the high pressure P of the compressor block diagram). 压缩机框图高压 ), and obtain the high pressure protection pressure threshold of the compressor (such as the high pressure protection high pressure P of the compressor). 高压保护 ); wherein the high pressure threshold of the compressor block diagram control and the high pressure protection pressure threshold of the compressor can be preset according to the performance of the compressor. The specific functions and processing of the acquisition unit 102 refer to step S110.

[0143] The control unit 104 is configured to control the high pressure threshold value and the high pressure protection pressure threshold value of the compressor according to the block diagram of the compressor, and determine the high pressure range of the compressor. The high pressure range of the compressor includes: pressure intervals, and the number of the pressure intervals is more than two; corresponding to each of the more than two pressure intervals, the corresponding frequency reduction amplitude of the compressor and the dwell time after the frequency reduction according to the frequency reduction amplitude of the compressor are set. The specific functions and processing of the control unit 104 refer to step S120.

[0144] The acquisition unit 102 is further configured to acquire the current high pressure of the compressor according to a preset sampling period after the variable frequency heat pump unit is powered on and the compressor is turned on, specifically to acquire the current exhaust pressure of the exhaust port of the compressor as the current high pressure of the variable frequency heat pump unit, and to acquire the current frequency of the compressor. The specific functions and processing of the acquisition unit 102 are also shown in step S130.

[0145] The control unit 104 is further configured to control the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, so as to adjust the current high pressure of the compressor to within the high pressure range of the compressor, so that the variable frequency heat pump unit operates within the high pressure range of the compressor, thereby ensuring the stable and reliable operation of the variable frequency heat pump unit. The specific functions and processing of the control unit 104 are also referred to step S140.

[0146] The solution of the present invention proposes a control method for a variable frequency heat pump unit, setting a high-pressure range with more than two pressure intervals, such as dividing multiple frequency reduction spaces in detail in combination with the compressor block diagram and the high-pressure switch protection value, so as to control the high pressure within a reasonable range, avoid frequent ultra-high pressure operation and high-pressure protection of the unit, make the unit operate stably and reliably, and ensure that the unit operates within a safe range.

[0147] In some implementations, the control unit 104 controls the high pressure threshold of the compressor and the high pressure protection pressure threshold of the compressor according to the block diagram of the compressor to determine the high pressure range of the compressor, including:

[0148] The control unit 104 is further configured to determine the difference between the block diagram control high pressure threshold of the compressor and the preset first pressure threshold as the frequency-limiting high pressure pressure threshold of the compressor, such as the compressor frequency-limiting high pressure pressure P 高压限频＝ P 压缩机框图高压 -△P1. The specific functions and processing of the control unit 104 are also referred to step S210. The preset first pressure threshold is such as △P1.

[0149] The control unit 104 is further configured to determine the difference between the block diagram control high pressure threshold of the compressor and the preset second pressure threshold as the first rate frequency reduction high pressure pressure threshold of the compressor, such as the compressor constant speed frequency reduction high pressure pressure P 高压常速降频＝ P 压缩机框图高压 -ΔP2. The specific functions and processing of the control unit 104 are also referred to step S220. The preset second pressure threshold is ΔP2.

[0150] The control unit 104 is further configured to determine the sum of the block diagram control high pressure threshold of the compressor and the preset third pressure threshold as the second rate frequency reduction high pressure pressure threshold of the compressor, such as the compressor rapid frequency reduction high pressure pressure P 高压快速降频＝ P 压缩机框图高压 +△P3. The specific functions and processing of the control unit 104 can also be found in step S230. The preset third pressure threshold is △P3.

[0151] The control unit 104 is further configured to determine the difference between the high-pressure protection pressure threshold of the compressor and the preset fourth pressure threshold as the third rate frequency reduction high-pressure pressure threshold of the compressor, such as the compressor rapid frequency reduction high-pressure pressure P 高压急速降频＝ P 高压保护 -ΔP4. The specific functions and processing of the control unit 104 can also be found in step S240. The preset fourth pressure threshold is ΔP4.

[0152] The control unit 104 is further configured to determine the fourth rate frequency reduction high pressure pressure threshold of the compressor by using the difference between the high pressure protection pressure threshold of the compressor and the preset fifth pressure threshold, such as the compressor rapid frequency reduction high pressure pressure P 高压飞速降频＝ P 高压保护 -ΔP5. The specific functions and processing of the control unit 104 are also shown in step S250.

[0153] The control unit 104 is further configured to determine the high pressure range of the compressor according to the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. The specific functions and processing of the control unit 104 are also shown in step S260. Among them, the high-pressure pressure range of the compressor includes: a pressure interval divided by the frequency-limited high-pressure pressure threshold of the compressor, the block diagram control high-pressure pressure threshold of the compressor, the first rate frequency reduction high-pressure pressure threshold of the compressor, the second rate frequency reduction high-pressure pressure threshold of the compressor, the third rate frequency reduction high-pressure pressure threshold of the compressor, the fourth rate frequency reduction high-pressure pressure threshold of the compressor, and the high-pressure protection pressure threshold of the compressor; that is, more than two of the pressure intervals are specifically divided by the frequency-limited high-pressure pressure threshold of the compressor, the block diagram control high-pressure pressure threshold of the compressor, the first rate frequency reduction high-pressure pressure threshold of the compressor, the second rate frequency reduction high-pressure pressure threshold of the compressor, the third rate frequency reduction high-pressure pressure threshold of the compressor, the fourth rate frequency reduction high-pressure pressure threshold of the compressor, and the high-pressure protection pressure threshold of the compressor.

[0154] In the solution of the present invention, it is defined as follows: the high pressure pressure of the unit monitored in real time by the high pressure sensor is P 高压压力 , compressor frequency limiting high pressure P 高压限频＝ P 压缩机框图高压 -△P1, compressor constant speed frequency reduction high pressure P 高压常速降频＝ P 压缩机框图高压 -△P2, compressor block diagram high pressure P 压缩机框图高压 , the compressor quickly reduces the frequency and high pressure P 高压快速降频＝ P 压缩机框图高压 +△P3, the compressor rapidly reduces the frequency and high pressure P 高压急速降频＝ P 高压保护 -△P4, the compressor rapidly reduces the frequency and high pressure P 高压飞速降频＝ P 高压保护 -△P5, compressor high pressure protection high pressure P 高压保护 .

[0155] Fig.11 This is a schematic diagram of compressor frequency reduction pressure. Fig.11 As shown, the high pressure relationship is P 高压限频 <P 高压常速降频 <P 压缩机框图高压 <P 高压快速降频 <P 高压急速降频 <P高压飞速降频 <P 高压保护 The pressure varies according to the type of refrigerant. For example, if it is R32 refrigerant, the pressure is P 高压限频 (4300kpa)<P 高压常速降频 (4350kpa)<P 压缩机框图高压 (4400kpa)<P 高压快速降频 (4450kpa)<P 高压急速降频 (4500kpa)<P 高压飞速降频 (4600kpa)<P 高压保护 (4700kpa).

[0156] In related schemes, variable frequency heat pump units generally limit the frequency reduction of the unit by exceeding a certain high pressure value to maintain the high pressure level, but this method is relatively simple. In the scheme of the present invention, a seven-fold pressure control method of frequency limiting, constant speed frequency reduction, super compressor block diagram, fast frequency reduction, rapid frequency reduction, rapid frequency reduction, and high pressure protection is adopted to control the high pressure within a reasonable range, avoid frequent ultra-high pressure operation and high pressure protection of the unit, and make the unit operate stably and reliably.

[0157] Fig.12 is a flow chart of an embodiment of a control method for a variable frequency heat pump unit, Fig.13 FIG. 2 is a flow chart of another embodiment of a control method for a variable frequency heat pump unit. Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit includes: step 1, after the compressor is turned on, the high-pressure sensor and high-pressure switch of the unit detect the high-pressure pressure, and then selectively execute at least one of step 2, step 3, step 4, step 5, step 6, step 7, and step 8 according to the actual situation.

[0158] In the scheme of the present invention, multiple frequency reduction spaces are divided in detail in combination with the compressor block diagram and the high-voltage switch protection value, and a seven-fold pressure control method of frequency limiting, normal speed frequency reduction, ultra-compressor block diagram, fast frequency reduction, rapid frequency reduction, rapid frequency reduction and high-voltage protection is adopted. Different frequency reduction amplitudes and residence times are used according to each divided pressure interval to control the high pressure within a reasonable range, avoid frequent ultra-high pressure operation and high pressure protection of the unit, make the unit operate stably and reliably, and ensure that the unit operates within a safe range.

[0159] In the related schemes, compressor frequency modulation, electronic expansion valve action, changes in operating conditions on the evaporation and condensation sides, extreme operating conditions such as low temperature and high humidity, high temperature and high humidity, and maximum operating temperature may cause the high pressure to exceed the expected range, or even high pressure protection. Generally, the pressure is controlled within the high pressure protection -△P range, leaving a margin to prevent frequent high pressure protection of the unit. In order to accurately control the high pressure range, the scheme of the present invention combines the compressor block diagram and the high-voltage switch characteristics, and proposes a seven-layer pressure control method. According to different pressure judgments, the frequency is limited in advance, and the frequency is reduced in stages. There is a buffer judgment time for the frequency reduction, which solves the problem of too much and too fast frequency reduction causing system instability and high pressure protection caused by excessive high pressure rushing. At the same time, it avoids the problem of frequent wear of the compressor due to over-compressor block diagram, ensuring stable operation of the unit.

[0160] In the scheme of the present invention, a seven-fold pressure control method of frequency limiting, constant speed frequency reduction, super compressor block diagram, rapid frequency reduction, rapid frequency reduction, rapid frequency reduction, and high-pressure protection is adopted to control the pressure within a reasonable range to avoid frequent ultra-high pressure operation and high-pressure protection of the unit. In order to determine the rationality of the set pressure value of the frequency reduction limit, it is necessary to comprehensively determine each pressure value through the compressor operation block diagram and the high-pressure switch protection value. Different frequency reduction amplitudes and dwell times are used according to the pressure of each divided interval to ensure non-ultra-high pressure operation and non-frequent high-pressure protection, so that the unit can operate stably and reliably.

[0161] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the compressor frequency limiting high pressure pressure threshold, the compressor block diagram control high pressure pressure threshold, the compressor first rate frequency reduction high pressure pressure threshold, the compressor second rate frequency reduction high pressure pressure threshold, the compressor third rate frequency reduction high pressure pressure threshold, the compressor fourth rate frequency reduction high pressure pressure threshold, and the compressor high pressure protection pressure threshold. The control unit 104 controls the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, including: the process of pressure control under a preset frequency limiting mode (such as a high pressure frequency limiting mode), as follows:

[0162] The control unit 104 is further configured to determine whether, after the compressor is started, it is continuously detected that the current high pressure of the compressor is greater than or equal to the frequency-limited high pressure pressure threshold of the compressor and less than the first rate frequency reduction high pressure pressure threshold of the compressor within the first set time under the preset frequency-limited mode. The specific functions and processing of the control unit 104 are also referred to step S310. Among them, the preset first set time under the frequency-limited mode, such as t 连续1 time.

[0163] The control unit 104 is also specifically configured to control the compressor to enter the preset frequency limiting mode to limit the increase of the current frequency of the compressor if it is determined that the current high pressure pressure of the compressor is greater than or equal to the frequency limiting high pressure pressure threshold of the compressor and less than the first rate frequency reduction high pressure pressure threshold of the compressor continuously within the first set time of the preset frequency limiting mode; then determine whether the current high pressure pressure of the compressor is less than the frequency limiting high pressure pressure threshold of the compressor continuously within the second set time of the preset frequency limiting mode; of course, if it is determined that the current high pressure pressure of the compressor is not greater than or equal to the frequency limiting high pressure pressure threshold of the compressor and less than the first rate frequency reduction high pressure pressure threshold of the compressor continuously within the first set time of the preset frequency limiting mode, then control the compressor to maintain the current operation, and return to re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor. Among them, the preset second set time under the frequency limiting mode, such as t 连续2 The specific functions and processing of the control unit 104 also refer to step S320.

[0164] The control unit 104 is also specifically configured to control the compressor to exit the preset frequency limiting mode after maintaining the current frequency of the compressor for a third set time in the preset frequency limiting mode if it is determined that the current high pressure pressure of the compressor is less than the frequency limiting high pressure pressure threshold of the compressor continuously within the second set time in the preset frequency limiting mode, so as to exit the restriction on the increase of the current frequency of the compressor and resume the control of the increase and decrease of the current frequency of the compressor. The specific functions and processing of the control unit 104 are also shown in step S330. Among them, the preset third set time in the frequency limiting mode, such as t in the frequency limiting mode, 连续3 time.

[0165] The control unit 104 is further configured to return to control the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor if it is determined that the current high pressure of the compressor is not detected to be less than the frequency-limiting high pressure pressure threshold of the compressor continuously within the second set time in the preset frequency-limiting mode. The specific functions and processing of the control unit 104 are also shown in step S340.

[0166] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 2, frequency limiting pressure control method. Frequency limiting: When the high pressure reaches a certain value, the compressor is not allowed to increase the frequency. At this time, it is necessary to maintain the current frequency to limit the increase of the compressor frequency; the compressor frequency limiting high pressure pressure P 高压限频＝ P 压缩机框图高压-△P1.

[0167] In step 2, after the compressor starts, if the continuous t 连续1 Time detected P 高压限频 ≤P 高压压力 <P 高压常速降频 , the compressor current frequency limit rises. If continuous t 连续2 Time detected P 高压压力 <P 高压限频 , maintain the current frequency F 当前 Continuous 连续3 After a certain time, the frequency limit is exited and the normal control pressure is restored without limit.

[0168] In the solution of the present invention, through frequency-limited pressure control, the high-pressure pressure reaches a certain value, and the compressor is not allowed to increase the frequency any further. At this time, it is necessary to maintain the current frequency to limit the increase in the compressor frequency, and limit the current frequency in advance to avoid excessive high pressure, thereby reducing frequent start-up and shutdown and high-pressure protection.

[0169] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the compressor's frequency-limited high pressure pressure threshold, the compressor's block diagram control high pressure pressure threshold, the compressor's first rate frequency reduction high pressure pressure threshold, the compressor's second rate frequency reduction high pressure pressure threshold, the compressor's third rate frequency reduction high pressure pressure threshold, the compressor's fourth rate frequency reduction high pressure pressure threshold, and the compressor's high pressure protection pressure threshold. The control unit 104 controls the current frequency of the compressor according to the compressor's current high pressure and the compressor's high pressure range, and also includes: a process of pressure control under a preset first rate frequency reduction mode (such as a normal speed frequency-limited mode), as follows:

[0170] The control unit 104 is further configured to determine, after the compressor is started, whether the current high pressure of the compressor is continuously detected to be greater than or equal to the first rate frequency reduction high pressure pressure threshold of the compressor and less than the block diagram control high pressure pressure threshold of the compressor within the first set time in the preset first rate frequency reduction mode. The specific functions and processing of the control unit 104 are also referred to step S410. The first set time in the preset first rate frequency reduction mode, such as t in the first rate frequency reduction mode, is greater than or equal to the first rate frequency reduction high pressure pressure threshold of the compressor. 连续1 time.

[0171] The control unit 104 is further specifically configured to control the compressor to enter the preset first rate reduction mode to control the current frequency of the compressor to reduce the preset first rate reduction value if it is determined that the current high-pressure pressure of the compressor is greater than or equal to the first rate reduction high-pressure pressure threshold of the compressor and is less than the block diagram control high-pressure pressure threshold of the compressor continuously within the first set time in the preset first rate reduction mode; and then re-determine whether it is continuously detected within the first set time in the preset first rate reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the first rate reduction high-pressure pressure threshold of the compressor and is less than the block diagram control high-pressure pressure threshold of the compressor: if so, control the The current frequency of the compressor is reduced by the preset first rate frequency reduction value every preset first rate frequency reduction time; otherwise, the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the first rate frequency reduction high pressure pressure threshold of the compressor and less than the first rate frequency reduction high pressure pressure threshold of the compressor within the first set time of the preset first rate frequency reduction mode, the compressor is controlled to maintain the current operation, and the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor. The specific functions and processing of the control unit 104 are also shown in step S420.

[0172] The control unit 104 is further configured to control the current frequency of the compressor to reduce the preset first rate frequency reduction value at every preset first rate frequency reduction time, and then determine whether the current high pressure pressure of the compressor is detected to be less than the first rate frequency reduction high pressure pressure threshold of the compressor within the second set time in the preset first rate frequency reduction mode. The specific functions and processing of the control unit 104 are also shown in step S430. The second set time in the preset first rate frequency reduction mode, such as t in the first rate frequency reduction mode, is 连续2 The preset first rate frequency reduction time is t 降频时间 , the preset first rate frequency reduction value is such as △F 常速降频 .

[0173] The control unit 104 is also specifically configured to control the compressor to exit the preset first rate frequency reduction mode after maintaining the current frequency of the compressor for a third set time in the preset first rate frequency reduction mode, if it is determined that the current high pressure pressure of the compressor is less than the first rate frequency reduction high pressure pressure threshold of the compressor continuously within the second set time in the preset first rate frequency reduction mode, so as to exit the current frequency reduction of the compressor controlled according to the preset first rate frequency reduction mode, and then re-control the current frequency of the compressor according to the current high pressure of the compressor and the high pressure pressure range of the compressor. The specific functions and processing of the control unit 104 can also be found in step S440. Among them, the third set time in the preset first rate frequency reduction mode, such as t in the first rate frequency reduction mode, is 连续3 time.

[0174] The control unit 104 is further configured to return to control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure range of the compressor if it is determined that the current high pressure pressure of the compressor is not detected to be less than the first rate frequency reduction high pressure pressure threshold of the compressor within the second set time in the preset first rate frequency reduction mode. The specific functions and processing of the control unit 104 are also shown in step S450.

[0175] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 3, a pressure control method of constant speed frequency reduction. Constant speed frequency reduction: When the high pressure exceeds the frequency limit pressure and reaches the pressure of constant speed frequency reduction, the compressor is not allowed to increase the frequency and must reduce the frequency at a certain speed to prevent the pressure from rising. Since there is still space between the high pressure and the boundary, only a small frequency △F needs to be reduced. 常速降频 ; Compressor normal speed frequency reduction high pressure P 高压常速降频＝ P 压缩机框图高压 -△P2.

[0176] In step 3, after the compressor starts, if the continuous t 连续1 Time detected P 高压常速降频 ≤P 高压压力 <P 压缩机框图高压 , when the condition is met for the first time, the frequency is immediately reduced △F 常速降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 常速降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 高压常速降频 , maintain the current frequency F 当前 Continuous 连续3After a certain time, exit the normal speed frequency reduction, and determine whether to resume normal control or enter frequency limit control according to the real-time monitoring pressure.

[0177] In the scheme of the present invention, through the pressure control of constant speed frequency reduction, the high pressure exceeds the frequency limit pressure and reaches the pressure of constant speed frequency reduction, the compressor is not allowed to increase the frequency and must reduce the frequency at a certain speed to prevent the pressure from rising. Since there is still room for the high pressure to reach the boundary, only a small frequency △F needs to be reduced. 常速降频 ; The frequency reduction is small and the unit reliability is high.

[0178] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the compressor's frequency-limited high pressure pressure threshold, the compressor's block diagram control high pressure pressure threshold, the compressor's first rate frequency reduction high pressure pressure threshold, the compressor's second rate frequency reduction high pressure pressure threshold, the compressor's third rate frequency reduction high pressure pressure threshold, the compressor's fourth rate frequency reduction high pressure pressure threshold, and the compressor's high pressure protection pressure threshold. The control unit 104 controls the current frequency of the compressor according to the compressor's current high pressure and the compressor's high pressure range, and also includes: a process of pressure control under a preset block diagram control mode (such as a compressor block diagram control mode), as follows:

[0179] The control unit 104 is further configured to determine whether, after the compressor is started, it is continuously detected within a first set time in a preset block diagram control mode that the current high pressure of the compressor is greater than or equal to the block diagram control high pressure pressure threshold of the compressor and less than the second rate reduction high pressure pressure threshold of the compressor. The specific functions and processing of the control unit 104 are also referred to step S510. The first set time in the preset block diagram control mode, such as t in the block diagram control mode, is continuously detected within a first set time in a preset block diagram control mode. 连续1 time.

[0180] The control unit 104 is further specifically configured to control the compressor to enter a preset block diagram control mode to control the current frequency of the compressor to reduce a preset block diagram control frequency reduction value if it is determined that the current high pressure pressure of the compressor is greater than or equal to the block diagram control high pressure pressure threshold of the compressor and is less than the second rate frequency reduction high pressure pressure threshold of the compressor continuously within a first set time under a preset block diagram control mode; and then re-determine whether it is continuously detected within a first set time under the preset block diagram control mode that the current high pressure pressure of the compressor is greater than or equal to the block diagram control high pressure pressure threshold of the compressor and is less than the second rate frequency reduction high pressure pressure threshold of the compressor: if so, control The current frequency of the compressor is reduced by the preset block diagram control frequency reduction value at every preset block diagram control time; otherwise, the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the block diagram control high pressure pressure threshold of the compressor and less than the block diagram control high pressure pressure threshold of the compressor within the first set time under the preset block diagram control mode, the compressor is controlled to maintain the current operation, and the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure range of the compressor. The specific functions and processing of the control unit 104 are also shown in step S520.

[0181] The control unit 104 is further configured to control the current frequency of the compressor to reduce the preset block diagram control frequency reduction value at every preset block diagram control time, and then determine whether it is continuously detected that the current high pressure pressure of the compressor is less than the block diagram control high pressure pressure threshold of the compressor within the second set time under the preset block diagram control mode. The specific functions and processing of the control unit 104 are also shown in step S530. The second set time under the preset block diagram control mode, such as t under the block diagram control mode, is 连续2 Time. The preset block diagram control time is t 降频时间 , the preset block diagram controls the frequency reduction value such as △F 常速降频 .

[0182] The control unit 104 is also specifically configured to control the compressor to exit the preset block diagram control mode after maintaining the current frequency of the compressor for the third set time in the preset block diagram control mode, if it is determined that the current high pressure pressure of the compressor is less than the block diagram control high pressure pressure threshold of the compressor continuously within the second set time in the preset block diagram control mode, so as to exit the current frequency reduction of the compressor controlled according to the preset block diagram control mode, and then re-control the current frequency of the compressor according to the current high pressure of the compressor and the high pressure pressure range of the compressor. The specific functions and processing of the control unit 104 can also be found in step S540. Among them, the third set time in the preset block diagram control mode, such as t in the block diagram control mode, 连续3 time.

[0183] The control unit 104 is also specifically configured to control the compressor to stop and the variable frequency heat pump unit to stop if it is determined that the current high pressure pressure of the compressor is not continuously detected within the second set time under the preset block diagram control mode and is not continuously detected within the continuous control time under the preset block diagram control mode and is not continuously detected that the current high pressure pressure of the compressor is less than the block diagram control high pressure pressure threshold of the compressor. The specific functions and processing of the control unit 104 are also shown in step S550. Among them, the continuous control under the preset block diagram control mode, such as t 压缩机框图持续 .

[0184] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 4, the pressure control method of the compressor block diagram. Super compressor block diagram: The high pressure has reached the limit of the range allowed for the compressor to operate. In order to ensure the reliability of the unit, a pressure margin is reserved and to prevent the high pressure from continuing to rise, the unit reduces △F 超框图降频 Frequency; High pressure compressor block diagram High pressure P 压缩机框图高压 .

[0185] In step 4, after the compressor starts, if the continuous t 连续1 Time detected P 压缩机框图高压 ≤P 高压压力 <P 高压快速降频 , when the condition is met for the first time, the frequency is immediately reduced △F 超框图降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 超框图降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 压缩机框图高压 , maintain the current frequency F 当前 Continuous 连续3After a certain time, the compressor block diagram control is exited, and the real-time monitoring pressure is used to determine whether to resume normal control or enter other pressure limit frequency reduction control; if continuous t 压缩机框图持续 If the high pressure still does not exit the compressor block diagram control during the operating time, the unit will shut down.

[0186] In the scheme of the present invention, through the pressure control of the compressor block diagram, the high pressure has reached the limit of the range allowed for the compressor to operate. In order to ensure the reliability of the unit, a pressure margin is reserved and to prevent the high pressure from continuing to rise, the unit reduces △F 超框图降频 The frequency is buffered; if the high pressure continues to rise for a certain period of time, the unit's super compressor block diagram will shut down.

[0187] In the related schemes, the electronic expansion valve and the compressor frequency are adjusted at the same time, and the external working conditions change in real time. If the coordination and control are not good, the high pressure of the unit is likely to exceed the range; that is, when the electronic expansion valve or the compressor frequency of the unit is adjusted too much, it is easy to cause the high pressure to exceed the range. In the scheme of the present invention, before the high pressure exceeds the range, the adjustment space margin is reserved to prevent the unit from running to high pressure protection every time, or reducing the frequency too quickly; in this way, the scheme of the present invention adopts the seven-level pressure control method to reduce the risk of over-adjustment of the unit and ensure the reliable operation of the unit.

[0188] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor; the control unit 104 controls the current frequency of the compressor according to the current high pressure of the compressor and the high pressure pressure range of the compressor, and also includes: a process of pressure control under a preset second rate frequency reduction mode (such as a fast frequency reduction mode), which is specifically as follows:

[0189] After the compressor is started, it is determined whether the current high pressure of the compressor is detected to be greater than or equal to the second rate frequency reduction high pressure pressure threshold of the compressor and less than the third rate frequency reduction high pressure pressure threshold of the compressor within the first set time in the preset second rate frequency reduction mode. The specific functions and processing of the control unit 104 are also referred to step S610. Among them, the first set time in the preset second rate frequency reduction mode, such as t in the second rate frequency reduction mode, is greater than or equal to the second rate frequency reduction high pressure pressure threshold of the compressor. 连续1 time.

[0190] The control unit 104 is further specifically configured to control the compressor to enter the preset second rate reduction mode to control the current frequency of the compressor to reduce the preset second rate reduction value if it is determined that the current high pressure pressure of the compressor is greater than or equal to the second rate reduction high pressure pressure threshold of the compressor and is less than the third rate reduction high pressure pressure threshold of the compressor within the first set time under the preset second rate reduction mode; and then re-determine whether it is detected that the current high pressure pressure of the compressor is greater than or equal to the second rate reduction high pressure pressure threshold of the compressor and is less than the third rate reduction high pressure pressure threshold of the compressor within the first set time under the preset second rate reduction mode: if so, control The current frequency of the compressor is controlled to reduce the preset second rate frequency reduction value every preset second rate frequency reduction time; otherwise, the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the second rate frequency reduction high pressure pressure threshold of the compressor and less than the second rate frequency reduction high pressure pressure threshold of the compressor within the first set time under the preset second rate frequency reduction mode, the compressor is controlled to maintain the current operation, and the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor. The specific functions and processing of the control unit 104 are also shown in step S620.

[0191] The control unit 104 is further configured to control the current frequency of the compressor to reduce the preset second rate frequency reduction value at every preset second rate frequency reduction time, and then determine whether the current high pressure pressure of the compressor is detected to be less than the second rate frequency reduction high pressure pressure threshold of the compressor continuously within the second set time in the preset second rate frequency reduction mode. The specific functions and processing of the control unit 104 are also shown in step S630. The second set time in the preset second rate frequency reduction mode, such as t in the second rate frequency reduction mode, is 连续2 The preset second rate frequency reduction time is t 降频时间 The preset second rate reduction value is △F 常速降频 .

[0192] The control unit 104 is also specifically configured to control the compressor to exit the preset second rate frequency reduction mode after maintaining the current frequency of the compressor for a third set time in the preset second rate frequency reduction mode, if it is determined that the current high pressure pressure of the compressor is less than the second rate frequency reduction high pressure pressure threshold of the compressor continuously within the second set time in the preset second rate frequency reduction mode, so as to exit the current frequency reduction of the compressor controlled according to the preset second rate frequency reduction mode, and then re-control the current frequency of the compressor according to the current high pressure of the compressor and the high pressure pressure range of the compressor. The specific functions and processing of the control unit 104 can also be found in step S640. Among them, the third set time in the preset second rate frequency reduction mode, such as t in the second rate frequency reduction mode, is 连续3 time.

[0193] The control unit 104 is also specifically configured to control the compressor to stop and the variable frequency heat pump unit to stop if it is determined that the current high pressure pressure of the compressor is not detected to be less than the second rate frequency reduction high pressure pressure threshold of the compressor within the second set time in the preset second rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not detected to be less than the second rate frequency reduction high pressure pressure threshold of the compressor within the continuous control time in the preset second rate frequency reduction mode. The specific functions and processing of the control unit 104 are also shown in step S650. Among them, the continuous control in the preset second rate frequency reduction mode, such as t 快速降频持续 .

[0194] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 5, a pressure control method for rapid frequency reduction. Rapid frequency reduction: The high pressure has exceeded the compressor block diagram range limit, but the excess is not much, to prevent further exceeding the range, and to allow the pressure to quickly return to the compressor block diagram range, the unit frequency reduction range is increased to reduce △F 快速降频 ; Compressor rapid frequency reduction high pressure P 高压快速降频＝ P 压缩机框图高压 +△P3.

[0195] In step 5, after the compressor starts, if the continuous t 连续1 Time detected P 高压快速降频 ≤P 高压压力 <P 高压急速降频 , when the condition is met for the first time, the frequency is immediately reduced △F 快速降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 快速降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P高压快速降频 , maintain the current frequency F 当前 Continuous 连续3 After a certain time, the system exits the rapid frequency reduction control and determines whether to resume normal control or enter other pressure-limited frequency reduction control according to the real-time monitoring pressure. 快速降频持续 If the high voltage still does not exit the rapid frequency reduction control during the operating time, the unit will shut down.

[0196] In the scheme of the present invention, through the pressure control of rapid frequency reduction, the high pressure has exceeded the compressor block diagram range limit, but the excess is not much, to prevent further exceeding the range, and to make the pressure quickly return to the compressor block diagram range, the unit frequency reduction amplitude is increased to reduce △F 快速降频 If the high pressure continues to rise for a certain period of time, the unit's super compressor block diagram will shut down.

[0197] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. The control unit 104 controls the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, and also includes: the process of pressure control under the preset third rate frequency reduction mode (such as rapid frequency reduction mode), which is specifically as follows:

[0198] The control unit 104 is further configured to determine, after the compressor is started, whether the current high pressure of the compressor is detected to be greater than or equal to the third rate frequency reduction high pressure pressure threshold of the compressor and less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the first set time in the third rate frequency reduction mode. The specific functions and processing of the control unit 104 are also referred to step S710. The first set time in the third rate frequency reduction mode is such as t in the third rate frequency reduction mode. 连续1 time.

[0199] The control unit 104 is further specifically configured to control the compressor to enter the preset third rate reduction mode to control the current frequency of the compressor to reduce the preset third rate reduction value if it is determined that the current high pressure pressure of the compressor is greater than or equal to the third rate reduction high pressure pressure threshold of the compressor and less than the fourth rate reduction high pressure pressure threshold of the compressor within the first set time in the preset third rate reduction mode; and then re-determine whether it is detected that the current high pressure pressure of the compressor is greater than or equal to the third rate reduction high pressure pressure threshold of the compressor and less than the fourth rate reduction high pressure pressure threshold of the compressor within the first set time in the preset third rate reduction mode: if so, control The current frequency of the compressor is controlled to be reduced by the preset third rate frequency reduction value at every preset third rate frequency reduction time; otherwise, the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the third rate frequency reduction high pressure pressure threshold of the compressor and less than the third rate frequency reduction high pressure pressure threshold of the compressor within the first set time of the preset third rate frequency reduction mode, the compressor is controlled to maintain the current operation, and the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor. The specific functions and processing of the control unit 104 are also shown in step S720.

[0200] The control unit 104 is further configured to control the current frequency of the compressor to reduce the preset third rate frequency reduction value at every preset third rate frequency reduction time, and then determine whether the current high pressure pressure of the compressor is detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the third set time in the preset third rate frequency reduction mode. The specific functions and processing of the control unit 104 are also shown in step S730. The third set time in the preset third rate frequency reduction mode, such as t in the third rate frequency reduction mode, is continuously detected within the third set time in the preset third rate frequency reduction mode. 连续2 The preset third rate frequency reduction time is t 降频时间 The preset third rate frequency reduction value is △F 常速降频 .

[0201] The control unit 104 is also specifically configured to control the compressor to exit the preset third rate frequency reduction mode after maintaining the current frequency of the compressor for the fourth time in the preset third rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset third rate frequency reduction mode, and then re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor if it is determined that the current high pressure pressure of the compressor is less than the third rate frequency reduction high pressure pressure threshold of the compressor continuously within the third set time in the preset third rate frequency reduction mode. The specific functions and processing of the control unit 104 can also be found in step S740. Among them, the fourth time in the preset third rate frequency reduction mode, such as t in the third rate frequency reduction mode, is 连续3 time.

[0202] The control unit 104 is further configured to control the compressor to stop and the variable frequency heat pump unit to stop if it is determined that the current high pressure pressure of the compressor is not detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the third set time in the preset third rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not detected to be less than the third rate frequency reduction high pressure pressure threshold of the compressor within the continuous control time in the preset third rate frequency reduction mode. The specific functions and processing of the control unit 104 are also shown in step S750. Among them, the continuous control in the preset third rate frequency reduction mode, such as t 急速降频持续 .

[0203] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 6, a pressure control method for rapid frequency reduction. Rapid frequency reduction: the high pressure has exceeded the compressor block diagram range limit by a certain pressure, to prevent further exceeding the range, the unit immediately increases the frequency reduction range △F 急速降频 ; The compressor rapidly reduces the frequency and high pressure P 高压急速降频＝ P 高压保护 -△P4.

[0204] In step 6, after the compressor starts, if the continuous 连续1 Time detected P 高压急速降频 ≤P 高压压力 <P 高压飞速降频 , when the condition is met for the first time, the frequency is immediately reduced △F 急速降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 急速降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 高压急速降频 , maintain the current frequency F当前 Continuous 连续3 After a certain time, the system will exit the rapid frequency reduction control and determine whether to resume normal control or enter other pressure-limited frequency reduction control according to the real-time monitoring pressure. 急速降频持续 If the high voltage still does not exit the rapid frequency reduction control during the operating time, the unit will shut down.

[0205] In the scheme of the present invention, through the pressure control of rapid frequency reduction, the high pressure has exceeded the compressor block diagram range limit by a certain pressure, to prevent further exceeding the range, the unit immediately increases the frequency reduction amplitude △F 急速降频 Let the pressure return to the compressor block diagram range quickly. If the high pressure continues to rise for a certain period of time, the unit will shut down.

[0206] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. The control unit 104 controls the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor, and also includes: a process of pressure control under a preset fourth rate frequency reduction mode (such as a rapid frequency reduction mode), which is specifically as follows:

[0207] The control unit 104 is further configured to determine, after the compressor is started, whether the current high pressure of the compressor is detected to be greater than or equal to the fourth rate frequency reduction high pressure pressure threshold of the compressor and less than the high pressure protection high pressure pressure threshold of the compressor within the first set time in the fourth rate frequency reduction mode. The specific functions and processing of the control unit 104 are also referred to step S810. The first set time in the fourth rate frequency reduction mode is such as t in the fourth rate frequency reduction mode. 连续1 time.

[0208] The control unit 104 is further specifically configured to control the compressor to enter the preset fourth rate reduction mode to control the current frequency of the compressor to reduce the preset fourth rate reduction value if it is determined that the current high-pressure pressure of the compressor is greater than or equal to the fourth rate reduction high-pressure pressure threshold of the compressor and is less than the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time in the preset fourth rate reduction mode; and then re-determine whether it is continuously detected within the first set time in the preset fourth rate reduction mode that the current high-pressure pressure of the compressor is greater than or equal to the fourth rate reduction high-pressure pressure threshold of the compressor and is less than the high-pressure protection high-pressure pressure threshold of the compressor: if so, control the The current frequency of the compressor is reduced by the preset fourth rate frequency reduction value at every preset fourth rate frequency reduction time; otherwise, the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor; of course, if it is determined that the current high pressure pressure of the compressor is not continuously detected to be greater than or equal to the fourth rate frequency reduction high pressure pressure threshold of the compressor and less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the first set time of the preset fourth rate frequency reduction mode, the compressor is controlled to maintain the current operation, and the current frequency of the compressor is controlled again according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor. The specific functions and processing of the control unit 104 can also be found in step S820.

[0209] The control unit 104 is further configured to control the current frequency of the compressor to reduce the preset fourth rate frequency reduction value at every preset fourth rate frequency reduction time, and then determine whether the current high pressure pressure of the compressor is detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the fourth time in the preset fourth rate frequency reduction mode. The specific functions and processing of the control unit 104 are also shown in step S830. The fourth time in the preset fourth rate frequency reduction mode, such as t in the fourth rate frequency reduction mode, is 连续2 The preset fourth rate frequency reduction time is t 降频时间 , the preset fourth rate frequency reduction value is such as △F constant speed frequency reduction.

[0210] The control unit 104 is also specifically configured to control the compressor to exit the preset fourth rate frequency reduction mode after maintaining the current frequency of the compressor for the fourth time in the preset fourth rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset fourth rate frequency reduction mode, and then re-control the current frequency of the compressor according to the current high pressure pressure of the compressor and the high pressure pressure range of the compressor if it is determined that the current high pressure pressure of the compressor is less than the fourth rate frequency reduction high pressure pressure threshold of the compressor continuously within the fourth time in the preset fourth rate frequency reduction mode. The specific functions and processing of the control unit 104 can also be found in step S840. Among them, the fourth time in the preset fourth rate frequency reduction mode, such as t in the fourth rate frequency reduction mode, is 连续3 time.

[0211] The control unit 104 is further configured to control the compressor to stop and the variable frequency heat pump unit to stop if it is determined that the current high pressure pressure of the compressor is not detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the fourth time period of the preset fourth rate frequency reduction mode, and it is determined that the current high pressure pressure of the compressor is not detected to be less than the fourth rate frequency reduction high pressure pressure threshold of the compressor within the continuous control time of the preset fourth rate frequency reduction mode. The specific functions and processing of the control unit 104 are also shown in step S850. Among them, the continuous control in the preset fourth rate frequency reduction mode, such as t 飞速降频持续 .

[0212] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 7, a pressure control method of rapid frequency reduction. Rapid frequency reduction: When the high pressure is about to reach the high pressure protection value, it is necessary to quickly reduce △F 飞速降频 ; The compressor rapidly reduces the frequency and high pressure P 高压飞速降频＝ P 高压保护 -△P5.

[0213] In step 7, after the compressor starts, if the continuous 连续1 Time detected P 高压飞速降频 ≤P 高压压力 <P 高压保护 , when the condition is met for the first time, the frequency is immediately reduced △F 飞速降频 , if this condition is still met after the frequency reduction, then F 当前 According to each t 降频时间 Reduce △F 飞速降频 Adjust until continuous t 连续2 Time detected P 高压压力 <P 高压飞速降频 , maintain the current frequency F 当前 Continuous 连续3After a certain time, the system will exit the rapid frequency reduction control and determine whether to resume normal control or enter other pressure limit frequency reduction control according to the real-time monitoring pressure. 飞速降频持续 If the high voltage still does not exit the rapid frequency reduction control during the operating time, the unit will shut down.

[0214] Among them, the frequency reduction relationship is △F 常速降频 <△F 超框图降频 <△F 快速降频 <△F 急速降频 <△F 飞速降频 For example: △F 常速降频 (2Hz)<△F 超框图降频 (4Hz)<△F 快速降频 (8Hz)<△F 急速降频 (10Hz)<△F 飞速降频 (12Hz).

[0215] The continuous running time and shutdown relationship is t 压缩机框图持续 >t 快速降频持续 >t 急速降频持续 >t 飞速降频持续 For example: 压缩机框图持续 (30min)>t 快速降频持续 (15min)>t 急速降频持续 (5min)>t 飞速降频持续 (3min).

[0216] In the solution of the present invention, through the rapid frequency reduction pressure control, the high pressure is about to reach the high pressure protection value, and it is necessary to quickly reduce △F 飞速降频 See if the high pressure can be unloaded. If the high pressure continues to rise for a certain period of time, the unit will shut down.

[0217] In some embodiments, the high pressure range of the compressor includes: a pressure interval divided by the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure pressure threshold of the compressor, the fourth rate frequency reduction high pressure pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor. The control unit 104 controls the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, and also includes: the process of pressure control under the preset high pressure protection mode, which is specifically as follows:

[0218] The control unit 104 is further configured to determine, after the compressor is started, whether the current high pressure of the compressor is detected to be greater than or equal to the high pressure protection high pressure threshold of the compressor continuously within the first set time in the preset high pressure protection mode. The specific functions and processing of the control unit 104 are also referred to step S910. The first set time in the preset fourth rate reduction mode, such as t 连续1 time.

[0219] The control unit 104 is also specifically configured to control the high-voltage switch of the variable frequency heat pump unit to disconnect and control the variable frequency heat pump unit to shut down if it is determined that the current high-voltage pressure of the compressor is greater than or equal to the high-voltage protection high-voltage pressure threshold of the compressor continuously within the first set time under the preset high-voltage protection mode; of course, if it is determined that the current high-voltage pressure of the compressor is not continuously detected within the first set time under the preset high-voltage protection mode to be greater than or equal to the high-voltage protection high-voltage pressure threshold of the compressor, the compressor is controlled to maintain the current operation, and returns to re-control the current frequency of the compressor according to the current high-voltage pressure of the compressor and the high-voltage pressure range of the compressor. The specific functions and processing of the control unit 104 are also shown in step S920.

[0220] like Fig.12 and Fig.13 As shown, the control method of the variable frequency heat pump unit also includes: step 8, a pressure control method for high pressure protection. High pressure protection: when the high pressure exceeds the protection value of the high pressure switch, the unit will shut down due to a fault; the high pressure protection pressure P of the compressor 高压保护 .

[0221] In step 8, after the compressor starts, if the continuous 连续1 Time detected P 高压压力 ≥P 高压保护 , the high-voltage switch is disconnected and the unit shuts down.

[0222] In the solution of the present invention, through the pressure control of high-pressure protection, if the high-pressure exceeds the protection value of the high-pressure switch, the unit will fail and shut down.

[0223] In the scheme of the present invention, a seven-fold pressure control method is proposed, including frequency limiting, constant speed frequency reduction, super compressor block diagram, fast frequency reduction, rapid frequency reduction, rapid frequency reduction, and high-pressure protection. Different frequency reduction amplitudes and dwell times are used according to each divided pressure interval to control the high pressure within a reasonable range. Thus, the problem of excessive high pressure range caused by over-adjustment of the electronic expansion valve or compressor frequency is solved, and frequent ultra-high pressure operation and high-pressure protection of the unit are avoided, so that the unit can operate stably and reliably.

[0224] Since the processing and functions implemented by the device of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0225] According to an embodiment of the present invention, a variable frequency heat pump unit corresponding to the control device of the variable frequency heat pump unit is also provided. The variable frequency heat pump unit may include: the control device of the variable frequency heat pump unit described above.

[0226] Since the processing and functions implemented by the variable frequency heat pump unit of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned device, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0227] According to an embodiment of the present invention, a computer program product corresponding to a variable frequency heat pump unit is also provided, including a computer program, which implements the steps of the control method of the variable frequency heat pump unit described above when executed by a processor.

[0228] Since the processing and functions implemented by the product of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned variable frequency heat pump unit, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0229] According to an embodiment of the present invention, a storage medium corresponding to the control method of the variable frequency heat pump unit is also provided, wherein the storage medium includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the steps of the control method of the variable frequency heat pump unit described above.

[0230] Since the processing and functions implemented by the storage medium of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0231] In summary, it is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0232] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A control method for a variable frequency heat pump unit, characterized in that: The variable frequency heat pump unit has a compressor; the control method of the variable frequency heat pump unit includes: Obtaining a block diagram control high pressure threshold of the compressor, and obtaining a high pressure protection pressure threshold of the compressor; Determine the high pressure range of the compressor according to the high pressure threshold of the compressor block diagram control and the high pressure protection pressure threshold of the compressor; After the variable frequency heat pump unit is powered on and the compressor is turned on, obtaining the current high pressure of the compressor and the current frequency of the compressor; According to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, the current frequency of the compressor is controlled to adjust the current high-pressure pressure of the compressor to within the high-pressure pressure range of the compressor.

2. The control method of the variable frequency heat pump unit according to claim 1, characterized in that: Controlling a high pressure threshold value of the compressor and a high pressure protection threshold value of the compressor according to the block diagram of the compressor to determine a high pressure range of the compressor includes: Determine the difference between the block diagram control high pressure threshold of the compressor and the preset first pressure threshold as the frequency-limiting high pressure threshold of the compressor; Determine the difference between the block diagram control high pressure threshold of the compressor and the preset second pressure threshold as the first rate frequency reduction high pressure threshold of the compressor; Determine the sum of the block diagram control high pressure threshold of the compressor and the preset third pressure threshold as the second rate frequency reduction high pressure threshold of the compressor; Determine the difference between the high-pressure protection pressure threshold of the compressor and the preset fourth pressure threshold as the third rate frequency reduction high-pressure pressure threshold of the compressor; Determine the fourth rate reduction high-pressure pressure threshold of the compressor by taking the difference between the high-pressure protection pressure threshold of the compressor and the preset fifth pressure threshold; The high pressure range of the compressor is determined based on the frequency-limited high pressure pressure threshold of the compressor, the block diagram control high pressure pressure threshold of the compressor, the first rate frequency reduction high pressure pressure threshold of the compressor, the second rate frequency reduction high pressure pressure threshold of the compressor, the third rate frequency reduction high pressure threshold of the compressor, the fourth rate frequency reduction high pressure threshold of the compressor, and the high pressure protection pressure threshold of the compressor.

3. The control method of the variable frequency heat pump unit according to claim 1 or 2, characterized in that: The high-pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor, which are successively increased; Controlling the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor includes: Determine whether it is continuously detected within a first set time in a preset frequency limiting mode that the current high pressure pressure of the compressor is greater than or equal to a frequency limiting high pressure pressure threshold of the compressor and less than a first rate frequency reduction high pressure pressure threshold of the compressor; If it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the frequency-limiting high-pressure pressure threshold of the compressor and less than the first rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time under the preset frequency-limiting mode, the compressor is controlled to enter the preset frequency-limiting mode to limit the increase of the current frequency of the compressor; then it is determined whether the current high-pressure pressure of the compressor is detected to be less than the frequency-limiting high-pressure pressure threshold of the compressor continuously within the second set time under the preset frequency-limiting mode; If it is determined that the current high-pressure pressure of the compressor is detected to be less than the frequency-limiting high-pressure pressure threshold of the compressor continuously within the second set time under the preset frequency-limiting mode, then after maintaining the current frequency of the compressor under the preset frequency-limiting mode for a third set time, the compressor is controlled to exit the preset frequency-limiting mode to exit limiting the increase of the current frequency of the compressor and resume the control of raising and lowering the current frequency of the compressor; If it is determined that the current high-pressure pressure of the compressor is not continuously detected to be less than the frequency-limiting high-pressure pressure threshold of the compressor within the second set time under the preset frequency-limiting mode, the control returns to re-control the current frequency of the compressor based on the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor.

4. The control method of the variable frequency heat pump unit according to any one of claims 1 to 3, characterized in that: The high-pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor, which are successively increased; Controlling the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, further comprising: Determine whether it is continuously detected within a first set time in a preset first rate frequency reduction mode that the current high pressure pressure of the compressor is greater than or equal to a first rate frequency reduction high pressure pressure threshold of the compressor and less than a block diagram control high pressure pressure threshold of the compressor; If it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and less than the block diagram control high-pressure pressure threshold of the compressor continuously within the first set time in the preset first rate frequency reduction mode, the compressor is controlled to enter the preset first rate frequency reduction mode to control the current frequency of the compressor to reduce the preset first rate frequency reduction value; then it is re-determined whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the first rate frequency reduction high-pressure pressure threshold of the compressor and less than the block diagram control high-pressure pressure threshold of the compressor continuously within the first set time in the preset first rate frequency reduction mode: if so, the current frequency of the compressor is controlled to reduce the preset first rate frequency reduction value at every preset first rate frequency reduction time; otherwise, the control is returned to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; After controlling the current frequency of the compressor to reduce the preset first rate frequency reduction value at every preset first rate frequency reduction time, determining whether it is continuously detected that the current high pressure pressure of the compressor is less than the first rate frequency reduction high pressure pressure threshold of the compressor within a second set time in the preset first rate frequency reduction mode; If it is determined that the current high-pressure pressure of the compressor is detected to be less than the first-rate frequency reduction high-pressure pressure threshold of the compressor continuously within the second set time in the preset first-rate frequency reduction mode, then after maintaining the current frequency of the compressor in the preset first-rate frequency reduction mode for a third set time, the compressor is controlled to exit the preset first-rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset first-rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; If it is determined that the current high-pressure pressure of the compressor is not continuously detected to be less than the first-rate frequency reduction high-pressure pressure threshold of the compressor within the second set time in the preset first-rate frequency reduction mode, the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor.

5. The control method of the variable frequency heat pump unit according to any one of claims 1 to 4, characterized in that: The high-pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor, which are successively increased; Controlling the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, further comprising: Determine whether it is continuously detected within a first set time in a preset block diagram control mode that the current high pressure pressure of the compressor is greater than or equal to a block diagram control high pressure pressure threshold of the compressor and less than a second rate reduction high pressure pressure threshold of the compressor; If it is determined that the current high-pressure pressure of the compressor is greater than or equal to the block diagram control high-pressure pressure threshold of the compressor and less than the second rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time under the preset block diagram control mode, the compressor is controlled to enter the preset block diagram control mode to control the current frequency of the compressor to reduce the preset block diagram control frequency reduction value; then it is re-determined whether the current high-pressure pressure of the compressor is greater than or equal to the block diagram control high-pressure pressure threshold of the compressor and less than the second rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time under the preset block diagram control mode: if so, the current frequency of the compressor is controlled to reduce the preset block diagram control frequency reduction value at every preset block diagram control time; otherwise, it returns to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; After controlling the current frequency of the compressor to be reduced by a preset block diagram control frequency reduction value at every preset block diagram control time, determining whether it is continuously detected that the current high pressure pressure of the compressor is less than the block diagram control high pressure pressure threshold value of the compressor within a second set time in the preset block diagram control mode; If it is determined that the current high-pressure pressure of the compressor is detected to be less than the block diagram control high-pressure pressure threshold of the compressor continuously within the second set time under the preset block diagram control mode, then after maintaining the current frequency of the compressor for a third set time under the preset block diagram control mode, the compressor is controlled to exit the preset block diagram control mode to exit the current frequency reduction of the compressor controlled according to the preset block diagram control mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; If it is determined that the current high-pressure pressure of the compressor is not continuously detected to be less than the block diagram control high-pressure pressure threshold of the compressor within the second set time under the preset block diagram control mode, and if it is determined that the current high-pressure pressure of the compressor is not continuously detected to be less than the block diagram control high-pressure pressure threshold of the compressor within the continuous control time under the preset block diagram control mode, the compressor is controlled to shut down, and the variable frequency heat pump unit is controlled to shut down.

6. The control method of the variable frequency heat pump unit according to any one of claims 1 to 5, characterized in that: The high-pressure range of the compressor includes: a pressure interval divided by a frequency-limited high-pressure pressure threshold of the compressor, a block diagram control high-pressure pressure threshold of the compressor, a first rate frequency reduction high-pressure pressure threshold of the compressor, a second rate frequency reduction high-pressure pressure threshold of the compressor, a third rate frequency reduction high-pressure pressure threshold of the compressor, a fourth rate frequency reduction high-pressure pressure threshold of the compressor, and a high-pressure protection pressure threshold of the compressor, which are successively increased; in, Controlling the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, further comprising: Determine whether it is continuously detected within a first set time in a preset second rate frequency reduction mode that the current high pressure pressure of the compressor is greater than or equal to a second rate frequency reduction high pressure pressure threshold of the compressor and less than a third rate frequency reduction high pressure pressure threshold of the compressor; If it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the second rate frequency reduction high-pressure pressure threshold of the compressor and less than the third rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time of the preset second rate frequency reduction mode, the compressor is controlled to enter the preset second rate frequency reduction mode to control the current frequency of the compressor to reduce the preset second rate frequency reduction value; then it is re-determined whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the second rate frequency reduction high-pressure pressure threshold of the compressor and less than the third rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time of the preset second rate frequency reduction mode: if so, the current frequency of the compressor is controlled to reduce the preset second rate frequency reduction value at every preset second rate frequency reduction time; otherwise, the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; After controlling the current frequency of the compressor to reduce the preset second rate frequency reduction value at every preset second rate frequency reduction time, determining whether it is continuously detected that the current high pressure pressure of the compressor is less than the second rate frequency reduction high pressure pressure threshold of the compressor within a second set time in the preset second rate frequency reduction mode; If it is determined that the current high-pressure pressure of the compressor is detected to be less than the second-rate frequency reduction high-pressure pressure threshold of the compressor continuously within the second set time in the preset second-rate frequency reduction mode, then after maintaining the current frequency of the compressor in the preset second-rate frequency reduction mode for a third set time, the compressor is controlled to exit the preset second-rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset second-rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; If it is determined that the current high-pressure pressure of the compressor is not detected to be less than the second rate-reduction high-pressure pressure threshold of the compressor within the second set time in the preset second rate-reduction frequency mode, and it is determined that the current high-pressure pressure of the compressor is not detected to be less than the second rate-reduction high-pressure pressure threshold of the compressor within the continuous control time in the preset second rate-reduction frequency mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop; and / or, Controlling the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, further comprising: Determine whether it is detected that the current high pressure pressure of the compressor is greater than or equal to the third rate frequency reduction high pressure pressure threshold of the compressor and less than the fourth rate frequency reduction high pressure pressure threshold of the compressor continuously within a first set time in the preset third rate frequency reduction mode; If it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the third-rate frequency reduction high-pressure pressure threshold of the compressor and less than the fourth-rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time in the preset third-rate frequency reduction mode, the compressor is controlled to enter the preset third-rate frequency reduction mode to control the current frequency of the compressor to reduce the preset third-rate frequency reduction value; then it is re-determined whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the third-rate frequency reduction high-pressure pressure threshold of the compressor and less than the fourth-rate frequency reduction high-pressure pressure threshold of the compressor continuously within the first set time in the preset third-rate frequency reduction mode: if so, the current frequency of the compressor is controlled to reduce the preset third-rate frequency reduction value at every preset third-rate frequency reduction time; otherwise, the control is returned to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; After controlling the current frequency of the compressor to decrease by a preset third rate frequency reduction value at every preset third rate frequency reduction time, determining whether it is continuously detected within a third set time in the preset third rate frequency reduction mode that the current high pressure pressure of the compressor is less than a third rate frequency reduction high pressure pressure threshold of the compressor; If it is determined that the current high-pressure pressure of the compressor is detected to be less than the third-rate frequency reduction high-pressure pressure threshold of the compressor continuously within the third set time in the preset third-rate frequency reduction mode, then after maintaining the current frequency of the compressor in the preset third-rate frequency reduction mode for a fourth time, the compressor is controlled to exit the preset third-rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset third-rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; If it is determined that the current high-pressure pressure of the compressor is not detected to be less than the third rate frequency reduction high-pressure pressure threshold of the compressor within the third set time in the preset third rate frequency reduction mode, and it is determined that the current high-pressure pressure of the compressor is not detected to be less than the third rate frequency reduction high-pressure pressure threshold of the compressor within the continuous control time in the preset third rate frequency reduction mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop; and / or, Controlling the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, further comprising: Determine whether it is continuously detected within a first set time in a preset fourth rate frequency reduction mode that the current high pressure of the compressor is greater than or equal to a fourth rate frequency reduction high pressure pressure threshold of the compressor and less than a high pressure protection high pressure pressure threshold of the compressor; If it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the fourth-rate frequency reduction high-pressure pressure threshold of the compressor and less than the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time in the preset fourth-rate frequency reduction mode, the compressor is controlled to enter the preset fourth-rate frequency reduction mode to control the current frequency of the compressor to reduce the preset fourth-rate frequency reduction value; then it is re-determined whether the current high-pressure pressure of the compressor is detected to be greater than or equal to the fourth-rate frequency reduction high-pressure pressure threshold of the compressor and less than the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time in the preset fourth-rate frequency reduction mode: if so, the current frequency of the compressor is controlled to reduce the preset fourth-rate frequency reduction value at every preset fourth-rate frequency reduction time; otherwise, the control is returned to re-control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; After controlling the current frequency of the compressor to decrease by a preset fourth rate frequency reduction value at every preset fourth rate frequency reduction time, determining whether it is continuously detected within a fourth time in the preset fourth rate frequency reduction mode that the current high pressure pressure of the compressor is less than a fourth rate frequency reduction high pressure pressure threshold of the compressor; If it is determined that the current high-pressure pressure of the compressor is detected to be less than the fourth-rate frequency reduction high-pressure pressure threshold of the compressor continuously within the fourth time in the preset fourth-rate frequency reduction mode, then after maintaining the current frequency of the compressor in the preset fourth-rate frequency reduction mode for the fourth time, the compressor is controlled to exit the preset fourth-rate frequency reduction mode, so as to exit the frequency reduction of the current frequency of the compressor controlled according to the preset fourth-rate frequency reduction mode, and then the current frequency of the compressor is controlled again according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor; If it is determined that the current high-pressure pressure of the compressor is not detected to be less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor within the fourth time period in the preset fourth rate frequency reduction mode, and it is determined that the current high-pressure pressure of the compressor is not detected to be less than the fourth rate frequency reduction high-pressure pressure threshold of the compressor within the continuous control time in the preset fourth rate frequency reduction mode, the compressor is controlled to stop, and the variable frequency heat pump unit is controlled to stop; and / or, Controlling the current frequency of the compressor according to the current high pressure of the compressor and the high pressure range of the compressor, further comprising: Determining whether it is continuously detected within a first set time in a preset high pressure protection mode that the current high pressure pressure of the compressor is greater than or equal to a high pressure protection high pressure threshold of the compressor; If it is determined that the current high-pressure pressure of the compressor is detected to be greater than or equal to the high-pressure protection high-pressure pressure threshold of the compressor continuously within the first set time in the preset high-pressure protection mode, the high-pressure switch of the variable frequency heat pump unit is controlled to be disconnected, and the variable frequency heat pump unit is controlled to be shut down.

7. A control device for a variable frequency heat pump unit, characterized in that: The variable frequency heat pump unit has a compressor; the control device of the variable frequency heat pump unit includes: an acquisition unit, configured to acquire a block diagram control high pressure threshold of the compressor, and acquire a high pressure protection pressure threshold of the compressor; a control unit configured to control a high pressure threshold value of the compressor and a high pressure protection pressure threshold value of the compressor according to a block diagram of the compressor, and determine a high pressure range of the compressor; The acquisition unit is further configured to acquire the current high pressure of the compressor and the current frequency of the compressor after the variable frequency heat pump unit is powered on and the compressor is turned on; The control unit is further configured to control the current frequency of the compressor according to the current high-pressure pressure of the compressor and the high-pressure pressure range of the compressor, so as to adjust the current high-pressure pressure of the compressor to within the high-pressure pressure range of the compressor.

8. A variable frequency heat pump unit, characterized in that: include: The control device of the variable frequency heat pump unit as claimed in claim 7.

9. A storage medium, characterized in that: The storage medium includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the control method of the variable frequency heat pump unit according to any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the control method of the variable frequency heat pump unit according to any one of claims 1 to 6 are implemented.

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