Variable frequency air conditioner and control method and control device thereof

Abstract

The application discloses a variable frequency air conditioner and a control method and a control device thereof, so as to improve the stability and reliability of the air conditioner system operation and realize the intelligent air conditioner function. The control method comprises the following steps: acquiring the current outdoor environment temperature when the variable frequency air conditioner operates; judging whether the current outdoor environment temperature meets the preset outer ring temperature condition; acquiring the current power module temperature and the current indoor temperature difference when the current outdoor environment temperature meets the preset outer ring temperature condition; controlling the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature and the current indoor temperature difference; and controlling the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature when the current outdoor environment temperature does not meet the preset outer ring temperature condition.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of air conditioning technology, in particular, it relates to an air conditioner, more particularly, it relates to a variable frequency air conditioner and a control method and control device thereof. BACKGROUND

[0002] Variable frequency air conditioners are widely used because of their fast temperature adjustment speed, high temperature control accuracy, low running noise and low energy consumption. A core component of a variable frequency air conditioner is a power module. The power module generates a large amount of heat and the temperature rises quickly when the variable frequency air conditioner is working. If the heat cannot be dissipated in time, the variable frequency air conditioner will malfunction or shut down due to the excessively high temperature of the power module, affecting the normal and stable operation of the air conditioner.

[0003] To improve the cooling effect of the power module, the existing variable frequency air conditioner uses refrigerant to cool the power module. Although the use of refrigerant can improve the cooling effect of the power module, the use of some refrigerant for cooling the power module will affect the amount of refrigerant provided by the air conditioner system to provide heating / cooling capacity, thereby affecting the cooling / heating capacity of the air conditioner.

[0004] In view of this, it is urgent to provide a technical solution that can balance the cooling / heating capacity of the air conditioner and the cooling capacity of the power module, and improve the stability and reliability of the operation of the air conditioner system. SUMMARY

[0005] One of the purposes of the present application is to provide a control method and control device for a variable frequency air conditioner, which balances the cooling / heating capacity of the air conditioner and the cooling capacity of the power module by controlling the opening degrees of two electronic expansion valves, improves the stability and reliability of the operation of the air conditioner system, and realizes the function of an intelligent air conditioner.

[0006] To achieve the above-mentioned purposes of the application, the control method for a variable frequency air conditioner provided by the present application adopts the following technical solution:

[0007] A control method for a variable frequency air conditioner, the variable frequency air conditioner comprising a power module, further comprising a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve being arranged in a main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve being arranged in a refrigerant branch circuit for cooling the power module;

[0008] The control method comprises:

[0009] When the variable frequency air conditioner is running, the current outdoor environment temperature is obtained;

[0010] It is judged whether the current outdoor environment temperature meets a preset outer ring temperature condition;

[0011] when the current outdoor environment temperature meets the preset outdoor ring temperature condition, obtaining a current power module temperature and a current indoor temperature difference, and controlling opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature and the current indoor temperature difference; the current indoor temperature difference is determined according to a current indoor temperature and a current set temperature;

[0012] when the current outdoor environment temperature does not meet the preset outdoor ring temperature condition, controlling the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature.

[0013] In some embodiments of the present application, controlling the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature and the current indoor temperature difference includes:

[0014] when the current indoor temperature difference meets a preset indoor temperature difference condition, performing the following control on the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature:

[0015] when the current power module temperature is less than a first temperature threshold, increasing the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be an initial opening degree;

[0016] when the current power module temperature is not less than the first temperature threshold and is less than a second temperature threshold, increasing the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree;

[0017] when the current power module temperature is not less than the second temperature threshold and is less than a third temperature threshold, and a change rate of the current power module temperature is greater than 0, maintaining the opening degree of the first electronic expansion valve and increasing the opening degree of the second electronic expansion valve.

[0018] In some embodiments of the present application, the control method further includes:

[0019] when the current power module temperature is not less than the third temperature threshold and the opening degree of the second electronic expansion valve reaches a second opening degree, controlling the variable frequency air conditioner to stop.

[0020] In some embodiments of the present application, controlling the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature and the current indoor temperature difference further includes:

[0021] when the current indoor temperature difference does not meet a preset indoor temperature difference condition, performing the following control on the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature:

[0022] when the current power module temperature is less than the first temperature threshold, maintaining the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree;

[0023] when the current power module temperature is less than the first temperature threshold, maintaining the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree;

[0024] when the current power module temperature is less than the first temperature threshold, maintaining the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree;

[0025] when the current power module temperature is less than the first temperature threshold, maintaining the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree.

[0026] In some embodiments of the present application, the control method further comprises:

[0027] when the current power module temperature is less than the first temperature threshold, maintaining the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree.

[0028] In some embodiments of the present application, when the current outdoor environment temperature does not satisfy the preset outer ring temperature condition, the control of the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature comprises:

[0029] when the current power module temperature is less than the first temperature threshold, maintaining the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree;

[0030] when the current power module temperature is less than the first temperature threshold, maintaining the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree.

[0031] when the current power module temperature is less than the first temperature threshold, maintaining the opening degree of the first electronic expansion valve and controlling the opening degree of the second electronic expansion valve to be a first opening degree.

[0032] In some embodiments of the present application, the control method further comprises:

[0033] control the variable frequency air conditioner to stop running when the current power module temperature is not less than the fifth temperature threshold.

[0034] To achieve the aforementioned purposes, the control device of the variable frequency air conditioner provided by the present application adopts the following technical solutions:

[0035] The control device of the variable frequency air conditioner comprises a power module, and further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, wherein the first electronic expansion valve is arranged in a main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in a refrigerant branch circuit for cooling the power module.

[0036] The control device comprises:

[0037] a current outdoor environment temperature acquisition unit configured to acquire a current outdoor environment temperature when the variable frequency air conditioner is running;

[0038] a current outdoor environment temperature judgment unit configured to judge whether the current outdoor environment temperature meets a preset outdoor ring temperature condition;

[0039] a current power module temperature acquisition unit configured to acquire a current power module temperature at least when the current outdoor environment temperature meets the preset outdoor ring temperature condition;

[0040] a current indoor temperature difference acquisition unit configured to acquire a current indoor temperature difference at least when the current outdoor environment temperature meets the preset outdoor ring temperature condition, wherein the current indoor temperature difference is determined according to a current indoor temperature and a current set temperature;

[0041] an expansion valve opening degree control unit configured to control opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature and the current indoor temperature difference when the current outdoor environment temperature meets the preset outdoor ring temperature condition, and to control the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature when the current outdoor environment temperature does not meet the preset outdoor ring temperature condition.

[0042] Still another purpose of the present application is to provide a variable frequency air conditioner comprising a power module, wherein the variable frequency air conditioner further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, wherein the first electronic expansion valve is arranged in a main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in a refrigerant branch circuit for cooling the power module; and the variable frequency air conditioner further comprises the control device of the variable frequency air conditioner described above.

[0043] Still another object of the present application is to provide an electronic device comprising a processor, a memory and a computer program stored on the memory, the processor being configured to execute the computer program to implement the control method of the variable frequency air conditioner.

[0044] Compared with the prior art, the present application has the advantages and positive effects that:

[0045] The variable frequency air conditioner, the control method and the control device provided by the present application set a first electronic expansion valve in the main refrigerant circuit and a second electronic expansion valve in the refrigerant branch circuit for cooling the power module, take the outdoor ambient temperature as the judgment parameter for regulating the opening degrees of the two electronic expansion valves, further combine the power module temperature and the indoor temperature difference to control the opening degrees of the two valves when the outdoor ambient temperature meets the preset outdoor ring temperature condition, so as to balance the cooling and heating capacity of the air conditioner and the cooling capacity of the power module; only control the opening degrees of the two valves according to the power module temperature when the outdoor ambient temperature does not meet the preset outdoor ring temperature condition, so as to cool the power module without affecting the cooling and heating capacity demand; thus, the stability and reliability of the air conditioner system operation are improved, and the intelligent variable frequency air conditioner function is realized.

[0046] Other features and advantages of the present application will become more apparent after reading the specific embodiments of the present application in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0048] Figure 1 is a structural schematic diagram of one embodiment of the variable frequency air conditioner of the present application;

[0049] Figure 2 is a flow schematic diagram of one embodiment of the control method of the variable frequency air conditioner of the present application;

[0050] Figure 3 is a flow schematic diagram of another embodiment of the control method of the variable frequency air conditioner of the present application;

[0051] Figure 4 is a structural schematic diagram of one embodiment of the control device of the variable frequency air conditioner of the present application;

[0052] Figure 5 is a structural schematic diagram of one embodiment of the electronic device of the present application. DETAILED DESCRIPTION

[0053] In order to make the objects, technical solutions and advantages of the present application clearer, further detailed description will be made to the present application with reference to the accompanying drawings and examples.

[0054] It should be noted that the technical solutions of various embodiments of the present application can be combined with each other, but it must be based on the implementation by ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection claimed by the present application.

[0055] In view of the problem that the existing variable frequency air conditioner lacks a reasonable distribution control technical solution for the refrigerant in the technology of using refrigerant to cool the power module, the present application creatively proposes to set a first electronic expansion valve in the refrigerant main circuit of the variable frequency air conditioner, set a second electronic expansion valve in the refrigerant branch for cooling the power module, take the outdoor environment temperature as the judgment parameter for regulating the opening degree of the two electronic expansion valves, select to use the power module temperature or the combination of the power module temperature and the indoor temperature difference to control the opening degree of the two electronic expansion valves according to the different outdoor environment temperature, realize the balance of the refrigeration and heating capacity of the air conditioner and the cooling capacity of the power module, improve the stability and reliability of the air conditioner system operation, and realize the intelligent variable frequency air conditioner function.

[0056] Figure 1 As shown in the structural schematic diagram of one embodiment of the variable frequency air conditioner of the present application.

[0057] As Figure 1 shown, the variable frequency air conditioner of this embodiment includes a compressor 11, a condenser 12, a first electronic expansion valve 14 and an evaporator 13 connected in sequence, constituting the refrigerant main circuit of the variable frequency air conditioner, and performing the refrigeration and heating cycle of the air conditioner. The variable frequency air conditioner further includes a power module (not shown in the figure) and a second electronic expansion valve 15, the second electronic expansion valve 15 is connected in parallel with the first electronic expansion valve 14 and is arranged in the refrigerant branch for cooling the power module. The variable frequency air conditioner further includes a control device 16 for realizing the control of the opening degree of the first electronic expansion valve 14 and the second electronic expansion valve 15. The specific control method and control process are described in the subsequent examples.

[0058] Among them, the refrigeration and heating cycle includes a series of processes, involving compression, condensation, expansion and evaporation, and refrigeration or heating for the indoor space.

[0059] The refrigeration working principle of the variable frequency air conditioner is that the compressor 11 works to make the evaporator 13 (at this time, the heat exchanger of the indoor unit) in a super-low pressure state, the liquid refrigerant in the evaporator 13 rapidly evaporates to absorb heat, and the wind blown by the indoor fan is cooled by the coil of the evaporator 13 and becomes cold wind to blow into the room. The evaporated refrigerant is pressurized by the compressor 11, and is condensed into liquid in the high-pressure environment of the condenser 12 (at this time, the heat exchanger of the outdoor unit), and releases heat, which is dissipated to the atmosphere by the outdoor fan, so that the refrigeration effect is achieved through the cycle.

[0060] The heating working principle of the variable frequency air conditioner is that the gaseous refrigerant is pressurized by the compressor 11 to become a high-temperature and high-pressure gas, enters the condenser 12 (at this time, the heat exchanger of the indoor unit), and is condensed to release heat to become a liquid, and at the same time, the indoor air is heated to achieve the purpose of increasing the indoor temperature. The liquid refrigerant is reduced in pressure by the first electronic expansion valve, enters the evaporator 13 (at this time, the heat exchanger of the outdoor unit), evaporates and absorbs heat to become a gas, and at the same time, absorbs the heat of the outdoor air (the outdoor air becomes cooler), and becomes gaseous refrigerant, which enters the compressor 11 again to start the next cycle.

[0061] Figure 2 Fig. 1 shows a flowchart of an embodiment of the control method of the variable frequency air conditioner. In this embodiment, the structure of the variable frequency air conditioner is shown in Fig. 1. Figure 1 As shown in Fig. 1, the variable frequency air conditioner comprises a power module, and further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve is arranged in the main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in the refrigerant branch circuit for cooling the power module.

[0062] As shown in Fig. 1, the variable frequency air conditioner comprises a power module, and further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve is arranged in the main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in the refrigerant branch circuit for cooling the power module. Figure 2 As shown in Fig. 1, the variable frequency air conditioner comprises a power module, and further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve is arranged in the main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in the refrigerant branch circuit for cooling the power module.

[0063] Step 21: When the variable frequency air conditioner is running, the current outdoor environment temperature is obtained.

[0064] The current outdoor environment temperature is the real-time temperature of the outdoor environment where the outdoor unit of the variable frequency air conditioner is located, which is obtained according to the set sampling frequency, and can be obtained by the temperature detection device arranged on the outdoor unit or obtained from a meteorological server through the Internet.

[0065] Step 22: It is judged whether the current outdoor environment temperature meets the preset outer ring temperature condition. If yes, step 23 is executed; otherwise, step 24 is executed.

[0066] The preset outer ring temperature condition is a known condition, which can be a fixed condition or a dynamically variable condition, and is used as a judgment condition for implementing different control strategies for the opening degree of the expansion valve. The setting principle of the preset outer ring temperature condition is that when the outdoor environment temperature does not satisfy the preset outer ring temperature condition, the temperature of the power module is reduced by sacrificing the refrigeration / heating capacity of the air conditioner, so as to realize the stable operation of the air conditioner.

[0067] In some embodiments, the preset outer ring temperature condition is that the outer ring temperature is not less than an outer ring temperature threshold. In some embodiments, the outer ring temperature threshold is 35℃. When the current outdoor environment temperature is not less than the outer ring temperature threshold, it is determined that the current outdoor environment temperature satisfies the preset outer ring temperature condition.

[0068] Step 23: obtaining the current power module temperature and the current indoor temperature difference, and controlling the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature and the current indoor temperature difference.

[0069] The current power module temperature is the temperature of the power module of the variable frequency air conditioner, which is obtained by a temperature detection device arranged on the surface of the power module. The current indoor temperature difference is the difference between the current indoor temperature of the indoor environment where the indoor unit of the variable frequency air conditioner is located and the current set temperature of the variable frequency air conditioner, which is obtained by a temperature detection device arranged on the surface of the power module.

[0070] When the outdoor environment temperature satisfies the preset outer ring temperature condition, the current power module temperature and the current indoor temperature difference are comprehensively considered, and the opening degrees of the first electronic expansion valve and the second electronic expansion valve are controlled according to the two temperatures as control parameters.

[0071] Step 24: obtaining the current power module temperature, and controlling the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature.

[0072] When the outdoor environment temperature does not satisfy the preset outer ring temperature condition, only the current power module temperature is obtained, and the opening degrees of the two electronic expansion valves are controlled according to the current power module temperature, without considering the influence of the indoor temperature difference.

[0073] The control method of this embodiment uses the outdoor environment temperature as a judgment parameter for regulating the opening degrees of the two electronic expansion valves. When the outdoor environment temperature satisfies the preset outer ring temperature condition, the opening degrees of the two valves are further controlled by combining the power module temperature and the indoor temperature difference, so as to balance the refrigeration / heating capacity of the air conditioner and the cooling capacity of the power module. When the outdoor environment temperature does not satisfy the preset outer ring temperature condition, the opening degrees of the two valves are controlled according to the power module temperature, so as to cool the power module without affecting the demand for refrigeration / heating capacity. Therefore, the stability and reliability of the air conditioner system operation are provided, and the intelligent variable frequency air conditioner function is realized.

[0074] Figure 3 Fig. 3 shows a flowchart of another embodiment of the control method of the variable frequency air conditioner of the present application. The structure of the variable frequency air conditioner in this embodiment is the same as that shown in Fig. 1, and thus will not be described again. Figure 1 As shown, the variable frequency air conditioner comprises the power module, and further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve is arranged in the main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in the refrigerant branch circuit for cooling the power module.

[0075] As shown in Fig. 3, the embodiment realizes the control of the air conditioner by using the following process. Figure 3 As shown in Fig. 3, the embodiment realizes the control of the air conditioner by using the following process.

[0076] Step 31: When the variable frequency air conditioner is running, the current outdoor environment temperature is obtained.

[0077] Step 32: It is judged whether the current outdoor environment temperature meets the preset outdoor ring temperature condition. If yes, step 33 is executed; otherwise, step 37 is executed.

[0078] Step 33: When it is judged that the current outdoor environment temperature meets the preset outdoor ring temperature condition, the current power module temperature and the current indoor temperature difference are obtained.

[0079] The specific implementation process, parameter meaning, parameter acquisition method, determination of the preset outdoor ring temperature condition, etc. of the above three steps are referred to the corresponding description of the embodiment. Figure 2 The corresponding description of the embodiment.

[0080] Step 34: It is judged whether the current indoor temperature difference meets the preset indoor temperature difference condition. If yes, step 35 is executed; otherwise, step 36 is executed.

[0081] The preset indoor temperature difference condition is a judgment condition for executing different control strategies of the opening degree of the electronic expansion valve when the current outdoor environment temperature meets the preset outdoor ring temperature condition, and is a known condition. The preset indoor temperature difference condition can be a fixed condition or a dynamically variable condition. The setting principle of the preset indoor temperature difference condition is that when the indoor temperature difference meets the preset indoor temperature difference condition, the refrigeration / heating capacity of the air conditioner is preferentially considered.

[0082] In some embodiments, the preset indoor temperature difference condition is that the indoor temperature difference is greater than a set temperature difference threshold. In some embodiments, the set temperature difference threshold is 4℃. When the current indoor temperature difference is greater than the set temperature difference threshold, it is judged that the current indoor temperature difference meets the preset indoor temperature difference condition. Then, different controls are executed according to whether the current indoor temperature difference meets the preset indoor temperature difference condition.

[0083] Step 35: According to the relationship between the current power module and the first temperature threshold, the second temperature threshold and the third temperature threshold, the opening degrees of the two electronic expansion valves are controlled.

[0084] When the current indoor temperature difference meets the preset indoor temperature difference condition, the opening degrees of the first electronic expansion valve and the second electronic expansion valve are controlled according to the relationship between the current power module temperature and the three temperature thresholds.

[0085] The specific control process includes:

[0086] (1) When the current power module temperature is less than the first temperature threshold, the opening degree of the first electronic expansion valve is increased, and the opening degree of the second electronic expansion valve is controlled to be the initial opening degree. By increasing the opening degree of the first electronic expansion valve, the refrigerant flow in the refrigerant main circuit is increased, the refrigeration / heating capacity of the air conditioner is improved, and the demand for indoor temperature regulation is quickly met. At the same time, the second electronic expansion valve maintains the initial opening degree, and the stable operation of the air conditioner system is maintained.

[0087] The first temperature threshold is a known value, which can be a fixed value or a dynamically variable value. In some embodiments, the first temperature threshold is 85°C.

[0088] The opening degree of the first electronic expansion valve can be increased by 10 pls based on the opening degree of the first electronic expansion valve determined by other control strategies currently used by the air conditioner.

[0089] The initial opening degree of the second electronic expansion valve is a known opening degree value. In some embodiments, the initial opening degree is 120 pls.

[0090] (2) When the current power module temperature is not less than the first temperature threshold and less than the second temperature threshold, the opening degree of the first electronic expansion valve is increased, and the opening degree of the second electronic expansion valve is controlled to be the first opening degree.

[0091] The first opening degree is a known opening degree value, and its value is greater than the initial opening degree. In some embodiments, the first opening degree is 150 pls. By increasing the opening degree of the first electronic expansion valve, the refrigerant flow in the refrigerant main circuit is increased, the refrigeration / heating capacity of the air conditioner is improved, and the demand for indoor temperature regulation is quickly met. At the same time, the second electronic expansion valve maintains the first opening degree, increases the cooling capacity of the power module, and realizes the stable operation of the air conditioner system.

[0092] The second temperature threshold is a known value, which is greater than the first temperature threshold, and can be a fixed value or a dynamically variable value. In some embodiments, the second temperature threshold is 90°C.

[0093] The opening degree of the first electronic expansion valve can be increased by 10 pls based on the opening degree of the first electronic expansion valve determined by other control strategies currently used by the air conditioner.

[0094] (3) when the current power module temperature is not less than the second temperature threshold and is less than the third temperature threshold, and the change rate of the current power module temperature is greater than 0, maintaining the opening degree of the first electronic expansion valve and increasing the opening degree of the second electronic expansion valve. By increasing the opening degree of the second electronic expansion valve, the cooling capacity of the power module is increased; at the same time, the opening degree of the first electronic expansion valve is maintained to maintain the stable operation of the system.

[0095] In some embodiments, the increase in the opening degree of the second electronic expansion valve cannot exceed the second opening degree. The second opening degree is a known opening degree, and its value is greater than the first opening degree. In some embodiments, the second opening degree is 350 pls.

[0096] The third temperature threshold is a known value, and its value is greater than the second temperature threshold. It can be a fixed value or a dynamically variable value. In some embodiments, the third temperature threshold is 105℃.

[0097] The change rate of the current power module temperature being greater than 0 indicates that the current power module temperature presents an upward trend.

[0098] Maintaining the opening degree of the first electronic expansion valve means that the opening degree of the first electronic expansion valve is no longer adjusted according to the power module temperature. The opening degree of the first electronic expansion valve is not necessarily a fixed opening degree. It can still work according to the opening degree determined by other control strategies.

[0099] In other embodiments, when the current indoor temperature difference meets the preset indoor temperature difference condition, the control method further comprises:

[0100] When the current power module temperature is not less than the third temperature threshold, and the opening degree of the second electronic expansion valve reaches the second opening degree, the variable frequency air conditioner is controlled to stop to avoid the adverse effects caused by the high power module temperature. In other embodiments, an alarm or a reminder of the high power module temperature is also issued.

[0101] Step 36: According to the relationship between the current power module and the first temperature threshold, the second temperature threshold, the third temperature threshold and the fourth temperature threshold, the opening degrees of the two electronic expansion valves are controlled.

[0102] When the current indoor temperature difference does not meet the preset indoor temperature difference condition, the opening degrees of the first electronic expansion valve and the second electronic expansion valve will be controlled according to the relationship between the current power module temperature and the four temperature thresholds. Compared with the control process of step 35, when the indoor temperature difference does not meet the preset indoor temperature difference threshold, the cooling / heating load demand is small, and more temperature thresholds are set by the fourth temperature threshold to realize slow adjustment of the valve opening degree, and the stability of the system operation is further improved.

[0103] The specific control process includes:

[0104] (1) When the current power module temperature is less than the first temperature threshold, keep the opening degree of the first electronic expansion valve, and control the opening degree of the second electronic expansion valve to be the first opening degree.

[0105] Since the refrigeration / heating load demand is small, the opening degree of the first electronic expansion valve is kept, and the second electronic expansion valve is controlled to be at a medium opening degree, so as to keep a certain cooling capacity for the power module, avoid the power module temperature being too high, and keep the stable operation of the air conditioner system.

[0106] (2) When the current power module temperature is not less than the first temperature threshold and less than the second temperature threshold, keep the opening degree of the first electronic expansion valve, and control the opening degree of the second electronic expansion valve to be the third opening degree. The third opening degree is a known value, and its value is greater than the first opening degree. In some embodiments, the third opening degree is 200 pls. When the power module temperature is not less than the first temperature threshold and is high, the second electronic expansion valve is controlled to operate at a larger third opening degree, so as to improve the cooling capacity for the power module.

[0107] (3) When the current power module temperature is not less than the second temperature threshold and less than the fourth temperature threshold, and the change rate of the current power module temperature is greater than 0, keep the opening degree of the first electronic expansion valve, and increase the opening degree of the second electronic expansion valve.

[0108] The fourth temperature threshold is a known value, and its value is greater than the second temperature threshold but less than the third temperature threshold. In some embodiments, the fourth temperature threshold is 100°C. When the power module temperature is further increased, the opening degree of the second electronic expansion valve is further increased, so as to improve the cooling capacity for the power module.

[0109] (4) When the current power module temperature is not less than the fourth temperature threshold and less than the third temperature threshold, and the opening degree of the second electronic expansion valve is not less than the third opening degree, reduce the opening degree of the first electronic expansion valve. By reducing the opening degree of the first electronic expansion valve, the refrigeration / heating capacity of the air conditioner is sacrificed, so that more refrigerant is used to cool the power module, and the stable and long-term operation of the air conditioner is realized.

[0110] In other embodiments, when the current indoor temperature difference does not satisfy the preset indoor temperature difference condition, the control method further comprises:

[0111] When the current power module temperature is not less than the third temperature threshold, and the opening degree of the second electronic expansion valve reaches the second opening degree, the variable frequency air conditioner is controlled to stop, so as to avoid the adverse effects caused by the high power module temperature. In other embodiments, an alarm or reminder of the high power module temperature is also issued.

[0112] Step 37: When it is determined in step 32 that the current outdoor environment temperature does not satisfy the preset outdoor ring temperature condition, the current power module temperature is obtained.

[0113] When the outdoor ambient temperature does not satisfy the preset outer ring temperature condition, only the current power module temperature is obtained, and the opening degrees of the two electronic expansion valves are controlled according to the current power module temperature, without considering the influence of the indoor temperature difference.

[0114] Step 38: According to the relationship between the current power module and the first temperature threshold, the second temperature threshold and the fifth temperature threshold, the opening degrees of the two electronic expansion valves are controlled.

[0115] When the current outdoor ambient temperature does not satisfy the preset outer ring temperature condition, the power module cooling is taken as the main control purpose, and the opening degrees of the first electronic expansion valve and the second electronic expansion valve are controlled according to the relationship between the current power module temperature and the three temperature thresholds.

[0116] The specific control process includes:

[0117] (1) When the current power module temperature is less than the first temperature threshold, the opening degree of the first electronic expansion valve is maintained, and the opening degree of the second electronic expansion valve is controlled to be the fourth opening degree.

[0118] The fourth opening degree is a known value, and the value is between the first opening degree and the third opening degree. In some embodiments, the fourth opening degree is 170 pls. By controlling the opening degree of the second electronic expansion valve to be the fourth opening degree, and maintaining the opening degree of the first electronic expansion valve, a certain cooling capacity for the power module can be maintained, the power module temperature is prevented from being too high, and the stable operation of the air conditioner system is maintained.

[0119] (2) When the current power module temperature is not less than the first temperature threshold and less than the second temperature threshold, and the change rate of the current power module temperature is greater than 0, the opening degree of the first electronic expansion valve is maintained, and the opening degree of the second electronic expansion valve is increased.

[0120] When the power module temperature further increases, the opening degree of the second electronic expansion valve is further increased, and the cooling capacity for the power module is improved.

[0121] (3) When the current power module temperature is not less than the second temperature threshold and less than the fifth temperature threshold, the opening degree of the first electronic expansion valve is reduced, and the opening degree of the second electronic expansion valve is increased, so as to improve the cooling capacity for the power module and enhance the power module cooling effect.

[0122] The fifth temperature threshold is a known value, and the value is less than the third temperature threshold. In some embodiments, the fifth temperature threshold is 95℃. When the current outdoor ambient temperature does not satisfy the preset outer ring temperature condition, by setting the fifth temperature threshold less than the third temperature threshold as the judgment temperature of whether to stop, the effective protection degree for the power module can be improved.

[0123] In some other embodiments, when the current outdoor ambient temperature does not satisfy the preset outdoor ring temperature condition, the control method further comprises:

[0124] When the current power module temperature is not less than the fifth temperature threshold, the control variable frequency air conditioner stops. Avoid the adverse effects caused by the high temperature of the power module. In some other embodiments, an alarm or a reminder of the high temperature of the power module is also sent out.

[0125] Figure 4 The structural schematic diagram of one embodiment of the control device of the variable frequency air conditioner of the present application is shown. The structure of the variable frequency air conditioner in this embodiment is shown in Figure 1 It comprises a power module, and further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve is arranged in the main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in the refrigerant branch circuit for cooling the power module.

[0126] The structural units included in the control device of this embodiment, the functions of the structural units and the relationship between them are as follows:

[0127] The control device comprises:

[0128] The current outdoor ambient temperature acquisition unit 41 is used to acquire the current outdoor ambient temperature when the variable frequency air conditioner is running.

[0129] The current outdoor ambient temperature judgment unit 42 is used to judge whether the current outdoor ambient temperature acquired by the current outdoor ambient temperature acquisition unit 41 satisfies the preset outdoor ring temperature condition.

[0130] The current power module temperature acquisition unit 43 is used to acquire the current power module temperature at least when the current outdoor ambient temperature judgment unit 42 determines that the current outdoor ambient temperature satisfies the preset outdoor ring temperature condition.

[0131] The current indoor temperature difference acquisition unit 44 is used to acquire the current indoor temperature difference at least when the current outdoor ambient temperature judgment unit 42 determines that the current outdoor ambient temperature satisfies the preset outdoor ring temperature condition. The current indoor temperature difference is determined according to the current indoor temperature and the current set temperature.

[0132] The expansion valve opening degree control unit 45 is used to control the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature acquired by the current power module temperature acquisition unit 43 and the current indoor temperature difference acquired by the current indoor temperature difference acquisition unit 44 when the current outdoor ambient temperature judgment unit 42 determines that the current outdoor ambient temperature satisfies the preset outdoor ring temperature condition; and is also used to control the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature acquired by the current power module temperature acquisition unit 43 when the current outdoor ambient temperature judgment unit 42 determines that the current outdoor ambient temperature does not satisfy the preset outdoor ring temperature condition.

[0133] The control device of the above structure runs the corresponding software program, performs the corresponding functions, and follows the instructions. Figure 2 , Figure 3 The control method embodiment and other embodiments of the variable frequency air conditioner control process are used to control the air conditioner to achieve the same effect as... Figure 2 , Figure 3 The corresponding technical effects of the embodiments and other embodiments.

[0134] The air conditioner control device described above is applied to a variable frequency air conditioner, which can improve the stability and reliability of the air conditioner system and realize the function of an intelligent air conditioner.

[0135] Figure 5 A structural block diagram of an embodiment of the electronic device of the present invention is shown. The electronic device includes a processor 51, a memory 52, and a computer program 521 stored in the memory 52. ​​The processor 51 is configured to execute the computer program 521 to implement… Figure 2 Implementation examples Figure 3 The embodiments and other embodiments describe air conditioner control methods and achieve the technical effects of the corresponding embodiments. The electronic equipment may be the main control board, controller, etc., of the air conditioner.

[0136] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions claimed by the present invention.

Claims

1. A control method of a variable frequency air conditioner including a power module, characterized by, The variable frequency air conditioner further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve is arranged in a main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in a refrigerant branch circuit for cooling the power module; The control method comprises: When the variable frequency air conditioner is running, a current outdoor environment temperature is obtained; It is judged whether the current outdoor environment temperature meets a preset outer ring temperature condition; When the current outdoor environment temperature meets the preset outer ring temperature condition, a current power module temperature and a current indoor temperature difference are obtained, and the opening degrees of the first electronic expansion valve and the second electronic expansion valve are controlled according to the current power module temperature and the current indoor temperature difference; the current indoor temperature difference is determined according to a current indoor temperature and a current set temperature; When the current outdoor environment temperature does not meet the preset outer ring temperature condition, the opening degrees of the first electronic expansion valve and the second electronic expansion valve are controlled according to the current power module temperature; Controlling the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature and the current indoor temperature difference comprises: When the current indoor temperature difference meets a preset indoor temperature difference condition, the opening degrees of the first electronic expansion valve and the second electronic expansion valve are controlled according to the current power module temperature as follows: When the current power module temperature is less than a first temperature threshold, the opening degree of the first electronic expansion valve is increased, and the opening degree of the second electronic expansion valve is controlled to be an initial opening degree; When the current power module temperature is not less than the first temperature threshold and is less than a second temperature threshold, the opening degree of the first electronic expansion valve is increased, and the opening degree of the second electronic expansion valve is controlled to be a first opening degree; When the current power module temperature is not less than the second temperature threshold and is less than a third temperature threshold, and a change rate of the current power module temperature is greater than 0, the opening degree of the first electronic expansion valve is kept, and the opening degree of the second electronic expansion valve is increased; When the current outdoor environment temperature does not meet the preset outer ring temperature condition, the opening degrees of the first electronic expansion valve and the second electronic expansion valve are controlled according to the current power module temperature, comprising: When the current power module temperature is less than the first temperature threshold, the opening degree of the first electronic expansion valve is kept, and the opening degree of the second electronic expansion valve is controlled to be a fourth opening degree; When the current power module temperature is not less than the first temperature threshold and is less than a second temperature threshold, and a change rate of the current power module temperature is greater than 0, the opening degree of the first electronic expansion valve is kept, and the opening degree of the second electronic expansion valve is increased; When the current power module temperature is not less than the second temperature threshold and is less than a fifth temperature threshold, the opening degree of the first electronic expansion valve is decreased, and the opening degree of the second electronic expansion valve is increased; the fifth temperature threshold is less than the third temperature threshold.

2. The control method of a variable frequency air conditioner according to claim 1, characterized by, The control method further comprises: When the current power module temperature is not less than the third temperature threshold, and the opening degree of the second electronic expansion valve reaches a second opening degree, the variable frequency air conditioner is controlled to stop.

3. The control method of a variable frequency air conditioner according to claim 2, characterized by, The control method further comprises: When the current power module temperature is not less than the fifth temperature threshold, the variable frequency air conditioner is controlled to stop. The variable frequency air conditioner further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve is arranged in a main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in a refrigerant branch circuit for cooling the power module. The control device comprises: A current outdoor environment temperature acquisition unit is configured to acquire a current outdoor environment temperature when the variable frequency air conditioner is running. A current outdoor environment temperature judgment unit is configured to judge whether the current outdoor environment temperature meets a preset outdoor ring temperature condition.

4. The control method of a variable frequency air conditioner according to claim 3, characterized by, A current power module temperature acquisition unit is configured to acquire a current power module temperature at least when the current outdoor environment temperature meets the preset outdoor ring temperature condition. A current indoor temperature difference acquisition unit is configured to acquire a current indoor temperature difference at least when the current outdoor environment temperature meets the preset outdoor ring temperature condition, the current indoor temperature difference being determined according to a current indoor temperature and a current set temperature.

5. The control method of a variable frequency air conditioner according to claim 1, characterized by, An expansion valve opening degree control unit is configured to control opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature and the current indoor temperature difference when the current outdoor environment temperature meets the preset outdoor ring temperature condition, and to control the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature when the current outdoor environment temperature does not meet the preset outdoor ring temperature condition. ​ 6. A control device of a variable frequency air conditioner, the variable frequency air conditioner comprising a power module, characterized in that, ​ ​ ​ ​ ​ ​ ​ The control of the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature comprises: When the current indoor temperature difference meets a preset indoor temperature difference condition, the control of the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature comprises: When the current power module temperature is less than a first temperature threshold, the opening degree of the first electronic expansion valve is increased, and the opening degree of the second electronic expansion valve is controlled as an initial opening degree; When the current power module temperature is not less than the first temperature threshold and less than a second temperature threshold, the opening degree of the first electronic expansion valve is increased, and the opening degree of the second electronic expansion valve is controlled as a first opening degree; When the current power module temperature is not less than the second temperature threshold and less than a third temperature threshold, and the change rate of the current power module temperature is greater than 0, the opening degree of the first electronic expansion valve is kept, and the opening degree of the second electronic expansion valve is increased. When the current outdoor environment temperature does not meet the preset outdoor ring temperature condition, the control of the opening degrees of the first electronic expansion valve and the second electronic expansion valve according to the current power module temperature comprises: When the current power module temperature is less than the first temperature threshold, the opening degree of the first electronic expansion valve is kept, and the opening degree of the second electronic expansion valve is controlled as a fourth opening degree; When the current power module temperature is not less than the first temperature threshold and less than a second temperature threshold, and the change rate of the current power module temperature is greater than 0, the opening degree of the first electronic expansion valve is kept, and the opening degree of the second electronic expansion valve is increased; When the current power module temperature is not less than the second temperature threshold and less than a fifth temperature threshold, the opening degree of the first electronic expansion valve is decreased, and the opening degree of the second electronic expansion valve is increased; the fifth temperature threshold is less than the third temperature threshold.

7. A variable frequency air conditioner comprising a power module, characterized by, The variable frequency air conditioner further comprises a first electronic expansion valve and a second electronic expansion valve connected in parallel, the first electronic expansion valve is arranged in a main refrigerant circuit of the variable frequency air conditioner, and the second electronic expansion valve is arranged in a refrigerant branch circuit for cooling the power module; the variable frequency air conditioner further comprises the variable frequency air conditioner control device in claim 6.

8. An electronic device comprising a processor, a memory, and a computer program stored on the memory, wherein, The processor is configured to execute the computer program to implement the control method of the variable frequency air conditioner in any one of claims 1 to 5. The processor is configured to execute the computer program to implement the control method of the variable frequency air conditioner in any one of claims 1 to 5.

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