Defrosting control method suitable for multiple scenes

Abstract

The invention relates to the technical field of heat pump cooling and heating equipment, and discloses a defrosting control method suitable for multiple scenes, which comprises the following specific steps: enabling a user to set a time threshold value and a temperature threshold value of a heat pump system; a defrosting judgment condition set of the heat pump system is set; the defrosting judgment condition group comprises a heating condition, an ultralow-temperature environment condition and a high-humidity environment condition; a defrosting quitting judgment condition is set; if any condition in the defrosting judgment condition set is met, the heat pump system is defrosted, in the defrosting process, time and temperature parameters of the heat pump system and the environment where the heat pump system is located are monitored in real time, whether a set defrosting quitting judgment condition is met or not is judged, and if the set defrosting quitting judgment condition is met, the heat pump system quits defrosting. Otherwise, the defrosting is continued. The method solves the problem that flexible adjustment cannot be carried out according to different climatic environments in the prior art, and has the characteristics that the unit operation performance can be improved, and the user comfort is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pump cooling and heating equipment, and more specifically, to a defrosting control method applicable to multiple scenarios. Background Art

[0002] During the use of heat pump cooling and heating equipment, especially in cold and humid environments, frost easily forms on the equipment surface, affecting its operating efficiency and service life. Traditional defrosting methods often cannot accurately judge the frosting situation, resulting in false defrosting or untimely defrosting, which in turn affects the user's comfort and the operating performance of the equipment.

[0003] The prior art has a defrost determination method for an air source heat pump unit. When the air source heat pump unit operates normally without frosting, the average value of the difference T between the ambient temperature and the fin temperature of the air source heat pump unit is calculated; when the air source heat pump unit operates normally at the operating site, the comparison value AT between the measured difference between the ambient temperature and the fin temperature and the difference T measured in the laboratory is stored; after the normal operating time of the unit is greater than the defrost interval time of the unit, the difference ST between the ambient temperature and the fin temperature of the frosted air source heat pump unit under different ambient temperatures and ambient humidity conditions is established; the difference QT between the ambient temperature and the fin temperature difference of the air source heat pump unit operating normally under different ambient temperatures and ambient humidity conditions and the ambient temperature and the fin temperature difference ST of the frosted air source heat pump unit under different ambient temperatures and ambient humidity conditions is calculated; when (T+AT)≤(ST-QT), it is determined that the air source heat pump needs to be defrosted to avoid the energy efficiency degradation of the unit caused by frequent defrosting.

[0004] However, the current heat pump defrost control method is relatively fixed and single, and its test conditions cannot be flexibly adjusted for different climate environments. Therefore, how to invent an intelligent defrost control method that can be flexibly adjusted for different climate environments is a technical problem that urgently needs to be solved in this technical field. Summary of the invention

[0005] In order to solve the problem that the prior art cannot be flexibly adjusted for different climate environments, the present invention provides a defrost control method and system applicable to multiple scenarios, which has the characteristics of improving the operating performance of the unit and improving the comfort of users.

[0006] In order to achieve the above-mentioned purpose of the present invention, the technical scheme adopted is as follows:

[0007] A defrosting control method applicable to multiple scenarios includes the following specific steps:

[0008] S1: Set the time threshold and temperature threshold of the heat pump system;

[0009] S2: Setting a defrost judgment condition group for the heat pump system; the defrost judgment condition group includes a temperature rise condition, an ultra-low temperature environment condition, and a high humidity environment condition;

[0010] The temperature rising condition includes the compressor continuous operation time condition item;

[0011] The ultra-low temperature environment condition includes a minimum temperature environment threshold environment;

[0012] The high humidity environment condition includes a difference condition item between the environment and the coil temperature;

[0013] Set the defrost exit judgment condition;

[0014] S3: If any condition in the defrost judgment condition group is met, the heat pump system will be defrosted. During the defrost process, the time and temperature parameters of the heat pump system and its environment are monitored in real time, and it is determined whether the set defrost exit judgment condition is met. If the set defrost exit judgment condition is met, the heat pump system exits defrosting and returns to step S2, otherwise it continues to defrost.

[0015] Preferably, in the step S1, the time threshold specifically includes the defrost cycle time D01; the temperature threshold specifically includes the inlet water temperature D02 for allowing defrosting, the coil temperature threshold D03 for exiting defrosting, the ambient temperature D04 for allowing defrosting, the set difference D05 between the ambient temperature for starting defrosting and the coil temperature, the defrost coil humidity difference threshold D06, the inlet water temperature D07 for allowing defrosting, the inlet water temperature threshold D08 for exiting defrosting, the coil temperature offset value D09 for exiting defrosting, the coil temperature offset value D10 for exiting defrosting, the special defrost low ambient temperature threshold D11, the defrost ambient temperature correction value FT, and the defrost return water correction value FW.

[0016] Furthermore, the temperature rise conditions are specifically as follows: the following conditions are met at the same time: the compressor continuous operation time tc ≥ C02 time; the ambient temperature Te ≤ D04 continues for T02 time; the coil temperature Tt ≤ D02 continues for T01 time; the difference between the ambient and coil temperatures △T ≥ the ring wing difference △Tf entering defrosting continues for T01 time; wherein △Tf = D08 + FT + FW; wherein T01 and T02 are respectively the preset first and second time thresholds; C02 is the preset second compressor minimum continuous operation time threshold.

[0017] Furthermore, the high humidity environmental conditions are specifically as follows: the following conditions are met simultaneously: the difference between the ambient and coil temperatures △T≥(△Tf+D06) lasts for a full T01 time; the coil temperature Tt≤D02 lasts for a full T01 time; the ambient temperature Te≤D04 lasts for a full T01 time; the cumulative running time of the compressor ttc≥the time to enter the defrost cycle (D01) / 2; wherein △Tf=D08+FT+FW; wherein T01 and T02 are respectively the preset first and second time thresholds; C02 is the preset second compressor minimum continuous running time threshold.

[0018] Furthermore, the ultra-low temperature environmental conditions are specifically: simultaneously satisfying: ambient temperature Te≤D11; coil temperature Tt≤D02; compressor cumulative operating time ttc≥C03; compressor continuous operating time tc≥C02; wherein C03 is the preset minimum cumulative operating time threshold.

[0019] Furthermore, in the step S2, a periodic defrosting judgment condition is also set;

[0020] The periodic defrost judgment conditions are specifically as follows: the cumulative running time of the compressor in the heating mode tH≥D01; the continuous running time of the compressor tc≥C01 time; the ambient temperature Te≤D04 continues for a full T01 time; the coil temperature Tt≤D02 continues for a full T01 time; the difference between the ambient and coil temperatures △T≥ the ring wing difference △Tf for entering defrost continues for a full T01 time; △Tf=D08+FT+FW; C01 is the preset first compressor continuous running time threshold.

[0021] Furthermore, in step S3, if the periodic defrost judgment condition in the defrost judgment condition group is met, the heat pump system enters the periodic defrost mode, exits the defrost mode every ts=D01 time, and enters the defrost mode every time the periodic defrost judgment condition is met.

[0022] Furthermore, the exit defrost judgment condition is specifically: satisfying any of the following exit conditions: coil temperature Tt≥D03 lasts for T03 time; defrost time ts≥D01; water inlet temperature Ti<D08; coil temperature failure and ts>T01; wherein T01 is the preset first time threshold, and T03 is the preset third time threshold.

[0023] Furthermore, the defrost exit judgment condition also includes an exit condition item: Tt≥(D03-D09), which lasts for T04 time; wherein T04 is a preset fourth time threshold.

[0024] Furthermore, the defrost exit judgment condition also includes an exit condition item: Tt≥(D03-D10), which lasts for T05 time; wherein T05 is a preset fifth time threshold.

[0025] The beneficial effects of the present invention are as follows:

[0026] The present invention provides an intelligent defrosting control method to solve the problems existing in the prior art. The present invention performs intelligent defrosting by combining different unit application conditions including the initial startup temperature rise stage, high humidity environment, and ultra-low temperature application scenario conditions, and operates different parameters for different frosting areas to avoid false defrosting. At the same time, the number of defrosting times can be reduced in the same time period, so that the unit is highly adapted to the climate environment, the unit operation performance is improved, and the user comfort is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of a defrosting control method applicable to multiple scenarios of the present invention.

[0028] Figure 2 It is a complete flow chart of a defrost control method applicable to multiple scenarios of the present invention in Example 3. DETAILED DESCRIPTION

[0029] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Example 1

[0031] like Figure 1 As shown, a defrosting control method applicable to multiple scenarios includes the following specific steps:

[0032] S1: Allow the user to set the time threshold and temperature threshold of the heat pump system;

[0033] S2: Setting a defrost judgment condition group for the heat pump system; the defrost judgment condition group includes a temperature rise condition, an ultra-low temperature environment condition, and a high humidity environment condition;

[0034] The temperature rising condition includes the compressor continuous operation time condition item;

[0035] The ultra-low temperature environment condition includes a minimum temperature environment threshold environment;

[0036] The high humidity environment condition includes a difference condition item between the environment and the coil temperature;

[0037] Set the defrost exit judgment condition;

[0038] S3: If any condition in the defrost judgment condition group is met, the heat pump system will be defrosted. During the defrost process, the time and temperature parameters of the heat pump system and its environment are monitored in real time, and it is determined whether the set defrost exit judgment condition is met. If the set defrost exit judgment condition is met, the heat pump system exits defrosting and returns to step S2, otherwise it continues to defrost.

[0039] Example 2

[0040] Specifically, in a specific embodiment, in the step S1, the time threshold specifically includes the defrost cycle time D01; the temperature threshold specifically includes the inlet water temperature D02 for allowing defrosting, the coil temperature threshold D03 for exiting defrosting, the ambient temperature D04 for allowing defrosting, the set difference D05 between the ambient temperature for starting defrosting and the coil temperature, the defrost coil humidity difference threshold D06, the inlet water temperature D07 for allowing defrosting, the inlet water temperature threshold D08 for exiting defrosting, the coil temperature offset value D09 for exiting defrosting, the coil temperature offset value D10 for exiting defrosting, the special defrost low ambient temperature threshold D11, the defrost ambient temperature correction value FT, and the defrost return water correction value FW.

[0041] In this embodiment, the units and precisions of the parameters set by the user and the preset factory setting parameters are shown in Table 1;

[0042] Table 1

[0043]

[0044]

[0045] In this embodiment, the defrost ambient temperature correction value FT and the defrost return water correction value FW are specifically shown in Table 2 and Table 3 respectively:

[0046] Table 2

[0047] FT(℃) (-∞,-20] (-20,-15] (-15,-10] (-10,-5] (-5,0] (0,5] (5,+∞] Correction value F01 F02 F03 F04 F05 F06 F07

[0048] Table 3

[0049] FW(℃) (-∞,20] (20,25] (25,40] (40,45] (45,50] (50,+∞] Correction value F08 F09 F10 F11 F12 F13

[0050] In the present embodiment, when the heat pump system is in the initial warm-up stage just after startup, since the state of the unit has not yet fully stabilized, defrosting at this time may lead to misjudgment or unnecessary energy consumption; therefore, the detection of the continuous operation time of the compressor is added, which means that after the continuous operation time of the compressor reaches the preset threshold C02 time, it is confirmed that the unit has truly entered a stable working state before considering starting the defrost program; the judgment of the ring-wing difference can enable the system to identify the frosting state more quickly, because when the difference between the outdoor ambient temperature and the fin temperature reaches the preset ring-wing difference, it can be judged that defrosting is required, and it can avoid entering the defrost program when defrosting is not required, thereby saving energy and avoiding energy efficiency reduction caused by defrosting too early or too late; in order to avoid triggering erroneous defrost instructions due to short-term temperature fluctuations, the ambient temperature and the coil temperature will be monitored at the same time to reach the allowable defrost temperature conditions and remain at the preset time before the defrost operation is performed.

[0051] In a specific embodiment, the temperature rise conditions are as follows: the following conditions are met at the same time: the compressor continuous operation time tc ≥ C02 time; the ambient temperature Te ≤ D04 lasts for T02 time; the coil temperature Tt ≤ D02 lasts for T01 time; the difference between the ambient and coil temperatures △T ≥ the ring wing difference △Tf entering defrost lasts for T01 time; △Tf = D08 + FT + FW; T01 and T02 are the preset first and second time thresholds respectively; C02 is the preset second compressor minimum continuous operation time threshold.

[0052] In this embodiment, when the water vapor content in the air is high in a high humidity environment, when these water vapors encounter the evaporator surface with a lower temperature, they are easily condensed into water droplets, and then form a frost layer. In the range of relative humidity>85%, frost is most serious, and the greater the humidity, the more frost there is. Therefore, the difference between the detection environment and the coil temperature and the defrosting coil temperature difference are introduced to determine the conditions for entering defrosting. At the same time, the defrosting operation is performed only when the monitoring environment temperature and the coil temperature reach the allowable defrosting temperature conditions and are maintained for a preset time, and the cumulative running time of the compressor reaches a preset value;

[0053] In a specific embodiment, the high humidity environmental conditions are specifically: the following conditions are met at the same time: the difference between the ambient and coil temperatures △T≥(△Tf+D06) lasts for a full T01 time; the coil temperature Tt≤D02 lasts for a full T01 time; the ambient temperature Te≤D04 lasts for a full T01 time; the cumulative running time of the compressor ttc≥the time to enter the defrost cycle (D01) / 2; wherein △Tf=D08+FT+FW; wherein T01 and T02 are the preset first and second time thresholds respectively; C02 is the preset second compressor minimum continuous running time threshold.

[0054] In this embodiment, when operating at an ultra-low ambient temperature, if the ambient temperature is detected to be lower than a preset value, it is automatically determined to be operating in an ultra-low temperature environment. At the same time, combined with the monitoring of the coil temperature value, the cumulative operating time of the compressor and the continuous operating time, timed defrosting is performed, which can effectively deal with the frosting problem at ultra-low ambient temperatures and ensure the efficient and stable operation of the heat pump system.

[0055] In a specific embodiment, the ultra-low temperature environmental conditions are specifically: simultaneously satisfying: ambient temperature Te≤D11; coil temperature Tt≤D02; compressor cumulative operating time ttc≥C03; compressor continuous operating time tc≥C02; wherein C03 is the preset minimum cumulative operating time threshold.

[0056] Example 3

[0057] More specifically, in this embodiment, the units, precisions and specific ranges of the parameters set by the user and the preset factory settings are shown in Table 4;

[0058] Table 4

[0059]

[0060]

[0061] like Figure 2 As shown, in a specific embodiment, in the step S2, a periodic defrosting judgment condition is also set;

[0062] The periodic defrost judgment conditions are specifically as follows: the cumulative running time of the compressor in the heating mode tH≥D01; the continuous running time of the compressor tc≥C01 time; the ambient temperature Te≤D04 continues for a full T01 time; the coil temperature Tt≤D02 continues for a full T01 time; the difference between the ambient and coil temperatures △T≥ the ring wing difference △Tf for entering defrost continues for a full T01 time; △Tf=D08+FT+FW; C01 is the preset first compressor continuous running time threshold.

[0063] In a specific embodiment, in step S3, if the periodic defrost judgment condition in the defrost judgment condition group is met, the heat pump system enters a periodic defrost mode, exits defrosting every ts=D01 time, and enters defrosting every time the periodic defrost judgment condition is met.

[0064] In a specific embodiment, the defrost exit judgment condition is specifically: satisfying any of the following exit conditions: coil temperature Tt≥D03 lasts for T03 time; defrost time ts≥D01; water inlet temperature Ti<D08; coil temperature failure and ts>T01; wherein T01 is the preset first time threshold, and T03 is the preset third time threshold.

[0065] In a specific embodiment, the defrost exit judgment condition further includes an exit condition item: Tt≥(D03-D09), which lasts for T04 time; wherein T04 is a preset fourth time threshold.

[0066] Furthermore, the defrost exit judgment condition also includes an exit condition item: Tt≥(D03-D10), which lasts for T05 time; wherein T05 is a preset fifth time threshold.

[0067] Obviously, the above embodiments of the present invention are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A defrosting control method applicable to multiple scenarios, characterized in that: The specific steps include: S1: Set the time threshold and temperature threshold of the heat pump system; S2: Setting a defrost judgment condition group for the heat pump system; the defrost judgment condition group includes a temperature rise condition, an ultra-low temperature environment condition, and a high humidity environment condition; The temperature rising condition includes the compressor continuous operation time condition item; The ultra-low temperature environment condition includes a minimum temperature environment threshold environment; The high humidity environment condition includes a difference condition item between the environment and the coil temperature; Set the defrost exit judgment condition; S3: If any condition in the defrost judgment condition group is met, the heat pump system will be defrosted. During the defrost process, the time and temperature parameters of the heat pump system and its environment are monitored in real time, and it is determined whether the set defrost exit judgment condition is met. If the set defrost exit judgment condition is met, the heat pump system exits defrosting and returns to step S2, otherwise it continues to defrost.

2. The defrosting control method applicable to multiple scenarios according to claim 1, characterized in that: In the step S1, the time threshold specifically includes the defrost cycle time D01; the temperature threshold specifically includes the inlet water temperature D02 for allowing defrosting, the coil temperature threshold D03 for exiting defrosting, the ambient temperature D04 for allowing defrosting, the set difference D05 between the ambient temperature for starting defrosting and the coil temperature, the defrost coil humidity difference threshold D06, the inlet water temperature D07 for allowing defrosting, the inlet water temperature threshold D08 for exiting defrosting, the coil temperature offset value D09 for exiting defrosting, the coil temperature offset value D10 for exiting defrosting, the special defrost low ambient temperature threshold D11, the defrost ambient temperature correction value FT, and the defrost return water correction value FW.

3. The defrosting control method applicable to multiple scenarios according to claim 2, characterized in that: The specific heating conditions are as follows: the following conditions are met at the same time: the compressor continuous operation time tc ≥ C02 time; the ambient temperature Te ≤ D04 continues for T02 time; the coil temperature Tt ≤ D02 continues for T01 time; the difference between the ambient and coil temperatures △T ≥ the ring wing difference △Tf entering defrosting continues for T01 time; △Tf = D08 + FT + FW; T01 and T02 are the preset first and second time thresholds respectively; C02 is the preset second compressor minimum continuous operation time threshold.

4. The defrosting control method applicable to multiple scenarios according to claim 2, characterized in that: The high humidity environmental conditions are specifically as follows: the following conditions are met simultaneously: the difference between the ambient and coil temperatures △T≥(△Tf+D06) lasts for a full T01 time; the coil temperature Tt≤D02 lasts for a full T01 time; the ambient temperature Te≤D04 lasts for a full T01 time; the cumulative running time of the compressor ttc≥the time to enter the defrost cycle (D01) / 2; △Tf=D08+FT+FW; T01 and T02 are the preset first and second time thresholds respectively; C02 is the preset second compressor minimum continuous running time threshold.

5. The defrosting control method applicable to multiple scenarios according to claim 2, characterized in that: The ultra-low temperature environmental conditions are specifically: simultaneously satisfying: ambient temperature Te≤D11; coil temperature Tt≤D02; compressor cumulative running time ttc≥C03; compressor continuous running time tc≥C02; wherein C03 is the preset minimum cumulative running time threshold.

6. The defrosting control method applicable to multiple scenarios according to claim 2, characterized in that: In the step S2, a periodic defrosting judgment condition is also set; The periodic defrost judgment conditions are specifically as follows: the cumulative running time of the compressor in the heating mode tH≥D01; the continuous running time of the compressor tc≥C01 time; the ambient temperature Te≤D04 continues for a full T01 time; the coil temperature Tt≤D02 continues for a full T01 time; the difference between the ambient and coil temperatures △T≥ the ring wing difference △Tf for entering defrost continues for a full T01 time; △Tf=D08+FT+FW; C01 is the preset first compressor continuous running time threshold.

7. The defrosting control method applicable to multiple scenarios according to claim 6, characterized in that: In step S3, if the periodic defrost judgment condition in the defrost judgment condition group is met, the heat pump system enters the periodic defrost mode, exits the defrost mode every ts=D01 time, and enters the defrost mode every time the periodic defrost judgment condition is met.

8. The defrosting control method applicable to multiple scenarios according to claim 2, characterized in that: The defrost exit judgment condition is specifically: satisfying any of the following exit conditions: coil temperature Tt≥D03 lasts for T03 time; defrost time ts≥D01; water inlet temperature Ti<D08; coil temperature failure and ts>T01; wherein T01 is the preset first time threshold, and T03 is the preset third time threshold.

9. The defrosting control method applicable to multiple scenarios according to claim 8, characterized in that: The defrost exit judgment condition also includes an exit condition item: Tt≥(D03-D09), which lasts for T04 time; wherein T04 is a preset fourth time threshold.

10. The defrosting control method applicable to multiple scenarios according to claim 8, characterized in that: The defrost exit judgment condition also includes an exit condition item: Tt≥(D03-D10), which lasts for T05 time; wherein T05 is a preset fifth time threshold.

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