[0054] As shown in Figure 2, the air conditioner system includes a compressor 8, an electromagnetic four-way reversing valve 9, an outdoor heat exchanger 10, a filter 11, a throttling electronic expansion valve 12, an indoor heat exchanger 13, and the indoor The heat exchanger 13 is divided into the indoor heat exchanger dehumidification section 13a and the indoor heat exchanger heating section 13b. A dehumidification solenoid valve is provided between the indoor heat exchanger dehumidification section 13a and the indoor heat exchanger heating section 13b. 14.
[0055] In order to achieve the purpose of intelligent control, several temperature and humidity sensors are installed in the air conditioner system, which are the indoor coil temperature sensor 16, the indoor temperature sensor 17, the indoor humidity sensor 18, the outdoor defrost temperature sensor 19, and the indoor coil temperature sensor. The outer ring temperature sensor 20, the compressor discharge temperature sensor 21, and the compressor suction temperature sensor 22.
[0056] The indoor coil temperature sensor 16 is located on the indoor heat exchanger dehumidification section 13a, the indoor temperature sensor 17 and the indoor humidity sensor 18 are located on the indoor heat exchanger 13, and the indoor humidity sensor 18 can detect room air humidity. In the dehumidifying state of the air conditioner, the on and off of the compressor 8 and the operating frequency are fuzzy controlled by the air conditioner controller according to the difference between the indoor humidity and the set humidity. The indoor temperature sensor 17 is used The operating frequency of the compressor 8 is controlled in the cooling and heating operation modes. The dehumidification operation mode is also controlled by the difference between the indoor temperature and the set temperature. The outdoor defrost temperature sensor 19 is located in the outdoor heat exchanger. Between 10 and the filter 11, the outdoor ambient temperature sensor 20 is used to control the rotation speed of the outdoor DC fan 15 or the ratio of the on-off time of the AC fan under the dehumidification state.
[0057] The outdoor fan 15 is a DC continuously variable speed motor or an AC motor with at least 2 wind speeds.
[0058] When the air conditioner is in the dehumidification operation mode, the throttling electronic expansion valve 12 is fully open, and the indoor dehumidification solenoid valve 14 is energized and is in throttling working state, which plays the role of throttling, pressure reduction and temperature reduction. The outdoor fan 15 is automatically controlled by the controller. Speed adjustment. In the dehumidification operation mode, due to the low rotation speed of the outdoor fan 15 or the constant on and off operation, the cooling capacity is low, so the high temperature and high pressure refrigerant discharged from the compressor 8 is only partially condensed in the outdoor heat exchanger 10. At the same time, because the throttling electronic expansion valve 12 is in the fully open state, the refrigerant in the outdoor heat exchanger 10 will be easily transported to the heating section 13b of the indoor heat exchanger. The indoor heat exchanger heating section 13b actually acts as a refrigeration system. A part of the condenser, due to the temperature of the refrigerant in the heating section 13b of the indoor heat exchanger, plays a role in heating the indoor air. It is cooled by the indoor air into a supercooled liquid, which is throttled by the dehumidification solenoid valve 14. The depressurization effect becomes a low-temperature and low-pressure gas-liquid mixed refrigerant vapor. In the dehumidification section 13a of the indoor heat exchanger, the refrigerant evaporates and cools down. Since its temperature is lower than the dew point temperature of the indoor air, the water vapor in the indoor air exchanges heat in the room. Condensation on the dehumidification section 13a of the heat exchanger reduces the indoor air humidity. The air heated through the heating section 13b of the indoor heat exchanger is mixed with the cooled and dehumidified air flowing through the dehumidification section 13a of the indoor heat exchanger, and then blown out from the indoor unit. The indoor temperature reaches the set temperature, and the humidity also reaches the set humidity.
[0059] By reasonably distributing the ratio of the dehumidification section 13a to the heating section 13b, as well as intelligent control of the throttling electronic expansion valve 12, dehumidification solenoid valve 14, outdoor fan 15 speed and compressor 8 operating frequency in the refrigeration system, cooling, dehumidification and constant temperature are realized. The purpose of dehumidification or heating and dehumidification.
[0060] In the normal cooling and heating operation state, the indoor dehumidification solenoid valve 14 is not energized and is in an open state. Due to the large flow diameter of the valve, the pressure loss of the refrigerant flowing through the valve can be ignored, and its existence will not affect Normal cooling and heating effect. The throttling and refrigerant flow adjustment at this time are completed by the throttling electronic expansion valve 12. Others, such as the control of the rotation speed of the outdoor fan 15 and the operating frequency of the compressor 8, are the same as the cooling and heating control methods in the prior art.
[0061] As shown in Figure 3, the control method of the constant temperature dehumidification air conditioner is as follows:
[0062] (1) The indoor temperature sensor 17 installed in the air conditioner detects the indoor temperature and compares the detected indoor temperature tr with the set temperature ts to obtain the temperature difference e. The temperature difference e conforms to the following expression, e= tr-ts, the set temperature ts is set by a controller such as a remote control;
[0063] (2) According to the temperature difference e obtained in step (1), the dehumidification operation mode of the air conditioner is divided into dehumidification and refrigeration zone and dehumidification and dehumidification zone, and further, the dehumidification and dehumidification zone is subdivided into cooling and dehumidification zone A', constant temperature dehumidification zone A, heating and dehumidification zone B, heating zone C;
[0064] (3) When the above temperature difference e≥3, the air conditioner is in the dehumidification and cooling zone. At this time, the indoor dehumidification solenoid valve 14 is de-energized and is in an open state. The air conditioner controller sends a cooling operation signal to the outdoor unit, and the frequency of the outdoor compressor 8 The control, the speed control of the outdoor fan 15 and the control of the throttling electronic expansion valve 12 are controlled according to the cooling operation mode. At this time, the air conditioner indoors will operate at a lower air outlet temperature to reduce the temperature of the indoor room while dehumidifying, reaching the desired value. Set temperature;
[0065] (4) When the above temperature difference e<3, the air conditioner is in the dehumidification and dehumidification area. At this time, the indoor dehumidification solenoid valve 14 is energized and is in a throttling state. The air conditioner controller sends a dehumidification operation signal to the outdoor unit, and the outdoor compressor 8 The frequency control, the speed control of the outdoor fan 15 and the control of the throttling electronic expansion valve 12 are controlled according to the dehumidification operation mode;
[0066] (5) Further, when the above temperature difference e<3, when the air conditioner is in the dehumidification and dehumidification zone, the zone is further subdivided. When 1≤e<3, it is set as the cooling and dehumidification zone A', when -1≤ When e<1, it is set as constant temperature dehumidification zone A, when -2
[0067] When the detected indoor temperature tr or the set temperature ts changes, resulting in a change in the temperature difference e, the air conditioner dynamically switches the corresponding operating mode at any time until the set requirements (which are set by the remote control and other controllers) are met , So that users can feel a comfortable indoor environment.
[0068] When the air conditioner is in the dehumidification and dehumidification area of the dehumidification operation mode, the outdoor throttle electronic expansion valve 12 is fully opened. At this time, the air conditioner adjusts the air output of the indoor heat exchanger 13 by adjusting the heat dissipation of the outdoor heat exchanger 10 Temperature, as known in the prior art, the greater the heat dissipation of the outdoor heat exchanger, the lower the air outlet temperature of the indoor heat exchanger.
[0069] There are two situations for controlling the heat dissipation of the outdoor heat exchanger 10:
[0070] The first situation: when the outdoor fan motor 15 adopts a DC continuously variable speed motor, the heat dissipation of the outdoor heat exchanger 10 is controlled by directly adjusting the speed of the outdoor fan 15.
[0071] Now according to Table 1, when the outdoor fan motor adopts a DC stepless variable speed motor, the control mode of the outdoor fan speed is described in detail:
[0072] Table 1
[0073] Outdoor ambient temperature
[0074] &SPEED-FAN-A', &SPEED-FAN-A, &SPEED-FAN-B, &SPEED-FAN-C, &SPEED-FAN-D are the corresponding outdoor fan speed variables in each area, among which &SPEED-FAN-A'> &SPEED-FAN-A>&SPEED-FAN-B>&SPEED-FAN-C≥&SPEED-FAN-D, the speed variable values are stored in the EEPROM of the outdoor unit, and different controls can be written according to the specifications of different air conditioners data.
[0075] Here is an example of an air conditioner of one specification:
[0076]When the outdoor ambient temperature detected by the outdoor ambient temperature sensor 20 is greater than 15°C, the outdoor fan speed is controlled according to the dehumidification operation area determined by the air conditioner indoor unit controller according to the above steps. When the air conditioner is in the cooling and dehumidifying zone A', The outdoor fan rotates at a high speed of 650 rpm to increase the heat dissipation of the outdoor heat exchanger 10 and reduce the air outlet temperature of the indoor heat exchanger 13. When the air conditioner is in the constant temperature dehumidification zone A, the outdoor fan rotates at 500 rpm. When the air conditioner is in the heating and dehumidifying zone B, the outdoor fan runs at 350 rpm. When the air conditioner is in the heating zone C, the outdoor fan runs at a low speed of 200 rpm to reduce the outdoor speed. The heat dissipation capacity of the heat exchanger 10 increases the air outlet temperature of the indoor heat exchanger 13; when the detected outdoor ambient temperature is less than or equal to 15°C, the outdoor fan 15 is forced to run at a low speed of 150 rpm. The speed is decreasing. When the frequency of the compressor 8 is 0, and it stops, the outdoor fan 15 also stops.
[0077] The second situation: when the outdoor fan motor 15 adopts an AC motor with at least 2 wind speeds, the heat dissipation of the outdoor heat exchanger 10 is controlled by adjusting the ratio of the on-off time of the outdoor fan 15.
[0078] Now according to Table 2, when the outdoor fan motor adopts an AC motor, the control mode of the outdoor fan on/off time ratio is described in detail.
[0079] Table 2
[0080] Outdoor ambient temperature
[0081] The parameters &TM_FAN-ON, &TM-FAN-OFF-A, &TM-FAN-OFF-B, &TM-FAN-OFF-C represent different open and stop times of outdoor fans, where &TM-FAN-OFF-A
[0082] Here is an example of an air conditioner of one specification:
[0083] When the outdoor ambient temperature detected by the outdoor ambient temperature sensor 20 is 38°C or higher, the air conditioner controller forces the outdoor fan 15 to continuously operate at a high speed (H) of 820 rpm.
[0084] When the outdoor environment temperature is between 31°C and 37°C, the outdoor fan 15 is forced to run continuously at a low speed (L) of 500 rpm.
[0085] When the outdoor environment temperature is below 18°C, the outdoor fan 15 is forced to shut down for a long time, and the shut down time is 70 seconds.
[0086] When the outdoor environment temperature is between 18°C and 30°C, the outdoor fan 15 will be switched on and off at different times according to the dehumidification operation area determined by the air conditioner indoor unit controller according to the above steps. When the air conditioner is in the cooling and dehumidifying zone A', The outdoor fan 15 runs continuously at a low speed (L) of 500 rpm. When the air conditioner is in the constant temperature dehumidification zone A, the outdoor fan 15 will stop for 30 seconds. When the air conditioner is in the heating dehumidification zone B, the outdoor fan The time for 15 to stop is 50 seconds. When the air conditioner is in the heating zone A, the time for the outdoor fan 15 to stop is 70 seconds, and the time for the outdoor fan 15 to stop is increasing. The longer the outdoor fan 15 is stopped, the less the heat dissipation of the outdoor heat exchanger 10 will be, and the higher the air outlet temperature of the indoor heat exchanger 13 will be.
[0087] When the frequency of the compressor 8 is 0, and it stops, the outdoor fan 15 also stops.
[0088] When the air conditioner is in the dehumidification operation mode, the operating frequency of the outdoor compressor 8 is fuzzy controlled based on the difference between the current indoor humidity detected by the indoor humidity sensor 18 installed in the air conditioner and the set humidity. The steps are:
[0089] a) The indoor humidity sensor 18 installed in the air conditioner detects the current indoor humidity, and compares the detected current indoor humidity with the set humidity (which is set by the remote control and other controllers). At this time, the air conditioner will The received relative humidity values are respectively converted into their corresponding dew point temperature according to the conversion method of the prior art, and the dew point temperature deviation e'of the two is obtained. The dew point temperature deviation e'conforms to the following expression, e'= current indoor humidity Corresponding dew point temperature-the dew point temperature corresponding to the set humidity;
[0090] b) After the dehumidification operation mode of the air conditioner is started, the target frequency of the compressor 8 is set to the rated dehumidification frequency DRY_F_ST, and then the controller calculates the dew point temperature deviation e'every 30 seconds, and performs a compressor frequency correction;
[0091] c) If the dew point temperature deviation e'≥2.0℃, the target frequency of compressor 8 is increased by 2Hz, and the upper limit of the target frequency is the maximum dehumidification frequency DRY_F_MAX;
[0092] When the dew point temperature deviation e'≤0.5°C, the target frequency of the compressor 8 drops by 2Hz, and the lower limit of the target frequency is the minimum dehumidification frequency DRY_F_MIN;
[0093] d) During the frequency increase of the compressor 8, when the indoor coil temperature sensor 16 of the air conditioner detects that the indoor coil temperature is too low, close to 0°C, the indoor coil temperature anti-freezing protection is implemented. At this time, the compressor 8 The frequency is forbidden to rise;
[0094] In the process of decreasing the frequency of the compressor 8, if the indoor coil temperature Texp+3>the current indoor dew point temperature, the frequency of stopping the compressor 8 decreases;
[0095] e) When the air conditioner is in the dehumidification operation mode and the outdoor ambient temperature is ≤ 0°C, the target frequency of the compressor 8 is set to 0 Hz;
[0096] f) When the air conditioner is in the dehumidification operation mode, and the current indoor humidity is ≤ (target setting humidity -10%), the target frequency of the compressor 8 is set to 0 Hz.
[0097] The above-mentioned compressor target frequency, dehumidification rated frequency DRY_F_ST, dehumidification maximum frequency DRY_F_MAX, dehumidification minimum frequency DRY_F_MIN and other parameters are all stored in the EEPROM data of the outdoor unit, and different controls can be written according to the specifications of different air conditioners data.
[0098] When the air conditioner is in the described dehumidification operation mode, the required indoor temperature can be set by a remote control and other controllers, but because the temperature and humidity can be set separately, in order to prevent unexpected temperatures when switching the dehumidification mode Setting and design control. When the indoor unit only receives the dehumidification and humidity adjustment signal, it defaults to the current indoor temperature as the set temperature. Only when the remote control adjusts the temperature signal is received, the set temperature is changed. When indoor humidity, the air conditioner works in the above-mentioned constant temperature dehumidification zone A mode.
[0099] As mentioned above, similar technical solutions can be derived from the content of the solutions given in the drawings and the embodiments. However, without departing from the technical solution of the present invention, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.
