Air conditioner and control method thereof

Abstract

The invention provides an air conditioner and a control method thereof.The air conditioner comprises a controller, and the controller is configured to control PFC channels to operate at the same current after a multi-channel PFC circuit is started; when the PFC channel operates with the same current, obtaining the temperature of a switch element of the PFC channel; determining an average temperature value of the switch elements in the multi-channel PFC circuit according to the temperatures of the switch elements of the PFC channels; determining a target current distribution coefficient of the PFC channel according to the average temperature value; and the current of the corresponding PFC channel is correspondingly adjusted according to the target current distribution coefficient of the PFC channel, so that the temperature of the switch element of the PFC channel is changed and finally kept consistent. According to the invention, the temperature balance control of the switch elements of a plurality of PFC channels can be realized, so that the temperatures of the switch elements are kept consistent, the condition that the PFC circuit is damaged due to overhigh temperatures of the switch elements is avoided, and the operation stability and reliability of the PFC circuit are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning, and in particular to an air conditioner and a control method of the air conditioner. Background Art

[0002] An interleaved PFC (Power Factor Correction) circuit is a circuit that sets multiple PFC channels in parallel and is applicable to two or more PFC channels.

[0003] In the related art, after the PFC circuit is started, the current values ​​of multiple PFC channels are usually controlled to maintain a balance, that is, current equalization control. However, in actual applications, due to certain deviations in the heat dissipation conditions, device parameters and circuit parameters of each switching element, maintaining the current balance of each PFC channel cannot ensure that the actual temperature value of each switching element is consistent. It is easy for one or some switching elements to have too high a temperature, causing damage to the PFC circuit, and the stability and safety of the PFC circuit operation are low. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0005] To this end, an object of the present invention is to provide an air conditioner that can achieve temperature balance control of switch elements of multiple PFC channels, so that the temperatures of each switch element remain consistent, avoiding the situation where the temperature of one or some switch elements is too high and causing damage to the PFC circuit, thereby improving the operating stability and reliability of the PFC circuit.

[0006] Therefore, a second object of the present invention is to provide a control method for an air conditioner.

[0007] In order to achieve the above-mentioned purpose, an embodiment of the first aspect of the present invention proposes an air conditioner, comprising: a casing; a refrigerant circulation loop, so that the refrigerant performs a refrigeration cycle in a loop composed of a compressor, a condenser, an electronic expansion valve, and an evaporator, wherein one of the condenser and the evaporator is an outdoor heat exchanger and the other is an indoor heat exchanger; a multi-channel PFC circuit, connected in parallel between a power input terminal and a power output terminal of the air conditioner, the multi-channel PFC circuit comprising a plurality of parallel PFC channels, for correcting an input current waveform of the air conditioner, wherein each of the PFC channels is provided with a switching element; and a temperature monitoring module, for monitoring the switching elements of each of the PFC channels. a controller configured to: after the multi-channel PFC circuit is started, control each of the PFC channels to operate at the same current; obtain the temperature of the switch element of each of the PFC channels in the process of each of the PFC channels operating at the same current; determine the average temperature value of the switch element in the multi-channel PFC circuit according to the temperature of the switch element of each of the PFC channels; determine the target current distribution coefficient of each of the PFC channels according to the average temperature value; and adjust the current size of the corresponding PFC channel according to the target current distribution coefficient of each of the PFC channels, so that the temperature of the switch element of each of the PFC channels changes and finally remains consistent.

[0008] According to the air conditioner of the embodiment of the present invention, by monitoring the temperature of the switching element, an average temperature value of the switching element is obtained, and the target current distribution coefficient of each PFC channel corresponding thereto is determined, and the current value of the corresponding PFC channel is reasonably distributed according to the target current distribution coefficient, so that the temperature value of the switching element is adjusted according to the distributed current value, so that the actual temperature value of the switching element tends to be consistent. Therefore, by determining the target current distribution coefficient corresponding to the average temperature value of the switching element and adjusting the current value of the PFC channel, the temperature balance control of the switching elements of multiple PFC channels can be achieved, so that the temperature of each switching element is kept consistent, and the situation that the temperature of one or some switching elements is too high, causing damage to the PFC circuit, is avoided, and the operation stability and reliability of the PFC circuit are improved.

[0009] In some embodiments, when adjusting the current size of the corresponding PFC channel according to the target current distribution coefficient of each PFC channel, the controller is configured to: obtain a total current target value of the multi-channel PFC circuit; obtain the target current of the corresponding PFC channel according to the product of the total current target value and the target current distribution coefficient of each PFC channel, and adjust the current of each PFC channel to the corresponding target current, so as to adjust the current size of the corresponding PFC channel.

[0010] In some embodiments, when determining the initial current distribution coefficient of each of the PFC channels according to the average temperature value, the controller is configured to: subtract the average temperature from the temperature of the switch element of each of the PFC channels, respectively, input the obtained differences into the temperature compensation controller for calculation, and then output the initial current distribution coefficient of each of the PFC channels respectively, wherein the temperature compensation controller is used to perform a proportional integral logic operation on the input differences.

[0011] In some embodiments, when determining the target current distribution coefficient of each of the PFC channels according to the average temperature value, if the temperature of the switch element of the PFC channel is higher, the corresponding initial current distribution coefficient and target current distribution coefficient are lower; if the temperature of the switch element of the PFC channel is lower, the corresponding initial current distribution coefficient and target current distribution coefficient are higher.

[0012] In some embodiments, when determining the target current distribution coefficient of each PFC channel according to the initial current distribution coefficient of each PFC channel, the controller is configured to: determine the current distribution coefficient of each PFC channel by the following formula, wherein the formula includes:

[0013] Rn=(R_Tn+R_OFFSET) / (R_T1+…+R_TN+R_OFFSET×N);

[0014] Among them, N is the number of the PFC channels, N is an integer greater than 1, n is the current PFC channel, Rn is the target current distribution coefficient of PFC channel n, R_Tn is the initial current distribution coefficient of PFC channel n, n is a positive integer and n is less than or equal to N, and R_OFFSET is a preset coefficient compensation offset value.

[0015] In some embodiments, when controlling each of the PFC channels to operate with the same current, the controller is configured to: divide the total current target value of the multi-channel PFC circuit according to the number of the PFC channels to obtain an equalized current; and control each of the PFC channels to operate with the equalized current.

[0016] In some embodiments, before determining the average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each of the PFC channels, the controller is further configured to: determine whether the multi-channel PFC circuit has run to a stable state; if it is determined that the multi-channel PFC circuit has run to a stable state, perform an action of determining the average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each of the PFC channels; if it is determined that the multi-channel PFC circuit has not run to a stable state, temporarily refrain from performing the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each of the PFC channels, until the multi-channel PFC circuit has not run to a stable state, then perform the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each of the PFC channels.

[0017] In some embodiments, when it is determined that the temperature of the switch element of each of the PFC channels is continuously and stably within a set temperature range within a set time period, it is determined that the multi-channel PFC circuit has run to a stable state.

[0018] In some embodiments, when adjusting the current value of each PFC channel to the corresponding target current value, the controller is further configured to: determine a PWM modulation pulse corresponding to the target current value of each PFC channel; and control the on or off time of the switch element according to the PWM modulation pulse to adjust the current value of each PFC channel.

[0019] In order to achieve the above-mentioned object, an embodiment of a second aspect of the present invention provides a control method for an air conditioner, comprising the following steps: after a multi-channel PFC circuit of the air conditioner is started, controlling each PFC channel in the multi-channel PFC circuit to operate with the same current, wherein the multi-channel PFC circuit comprises a plurality of PFC channels connected in parallel, and each of the PFC channels is provided with a switch element; in the process of each of the PFC channels operating with the same current, acquiring the temperature of the switch element of each of the PFC channels; determining an average temperature value of the switch element in the multi-channel PFC circuit according to the temperature of the switch element of each of the PFC channels; determining a target current distribution coefficient of each of the PFC channels according to the average temperature value; and adjusting the current size of the corresponding PFC channel according to the target current distribution coefficient of each of the PFC channels, so that the temperature of the switch element of each of the PFC channels changes and finally remains consistent.

[0020] According to the control method of the PFC circuit of the embodiment of the present invention, by monitoring the temperature of the switching element, an average temperature value of the switching element is obtained, and the target current distribution coefficient of each PFC channel corresponding thereto is determined, and the current value of the corresponding PFC channel is reasonably distributed according to the target current distribution coefficient, so that the temperature value of the switching element is adjusted according to the distributed current value, so that the actual temperature value of the switching element tends to be consistent. Therefore, by determining the target current distribution coefficient corresponding to the average temperature value of the switching element and adjusting the current value of the PFC channel, the temperature balance control of the switching elements of multiple PFC channels can be achieved, so that the temperature of each switching element is kept consistent, and the situation that the temperature of one or some switching elements is too high, causing damage to the PFC circuit, is avoided, and the operation stability and reliability of the PFC circuit are improved.

[0021] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0023] Figure 1 is a structural schematic diagram of an air conditioner according to an embodiment of the present invention;

[0024] Figure 2 is a hardware configuration block diagram of a controller according to an embodiment of the present invention;

[0025] Figure 3 is a structural block diagram of an air conditioner according to an embodiment of the present invention;

[0026] Figure 4 is a schematic diagram of a control method for a PFC circuit of an air conditioner according to an embodiment of the present invention;

[0027] Figure 5 is a circuit diagram of an air conditioner according to an embodiment of the present invention;

[0028] Figure 6 is a flow chart of a control method of a PFC circuit of an air conditioner according to an embodiment of the present invention;

[0029] Figure 7 is a flow chart of a control method of a PFC circuit according to an embodiment of the present invention.

[0030] Description of the drawings: air conditioner 100;

[0031] Indoor unit 11; air outlet 12; return air outlet 13; outdoor unit 14;

[0032] Wind deflector 2; control device 200;

[0033] Controller 71;

[0034] Bus 81; Memory 82; Processor 83; Communication interface 84;

[0035] Casing 101 ; refrigerant circulation circuit 102 ; multi-channel PFC circuit 103 ; temperature monitoring module 104 . DETAILED DESCRIPTION

[0036] The present invention is described in detail below by way of exemplary embodiments. However, it should be understood that elements, structures, and features in one embodiment may also be beneficially combined in other embodiments without further description.

[0037] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0038] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] The embodiment of the present invention provides an air conditioner 100, referring to Figure 1 The air conditioner 100 includes a refrigeration system for exchanging heat with indoor air to meet cooling or heating needs.

[0041] The refrigeration system includes a compressor, a condenser, an expansion valve, and an evaporator, and the air conditioner 100 in the present invention performs a refrigeration cycle of the air conditioner 100 by using the compressor, the condenser, the expansion valve, and the evaporator. The refrigeration cycle includes a series of processes involving compression, condensation, expansion, and evaporation, and supplies refrigerant to the conditioned and heat-exchanged air.

[0042] The compressor compresses the refrigerant gas in a high temperature and high pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and the heat is released to the surrounding environment through the condensation process.

[0043] The expansion valve expands the high-temperature and high-pressure liquid refrigerant condensed in the condenser into a low-pressure liquid refrigerant. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the low-temperature and low-pressure refrigerant gas to the compressor.

[0044] The evaporator can achieve a refrigeration effect by using the latent heat of evaporation of the refrigerant to perform heat exchange with the material to be cooled. In the whole cycle, the air conditioner 100 can adjust the temperature of the indoor space.

[0045] The outdoor unit of the air conditioner 100 refers to a portion of a refrigeration cycle including a compressor and an outdoor heat exchanger, the indoor unit of the air conditioner 100 includes an indoor heat exchanger, and an expansion valve may be provided in the indoor unit or the outdoor unit.

[0046] The indoor heat exchanger and the outdoor heat exchanger function as a condenser or an evaporator. When the indoor heat exchanger functions as a condenser, the air conditioner 100 functions as a heater in a heating mode, and when the indoor heat exchanger functions as an evaporator, the air conditioner 100 functions as a cooler in a cooling mode.

[0047] The air conditioner 100 of the present invention includes an indoor unit 11 and an outdoor unit 14, and the indoor unit 11 and the outdoor unit 14 can be set as an integrated unit or a split unit. The indoor unit 11 can be set as a wall-mounted type, a ceiling unit, a duct unit, etc., and the indoor unit 11 is installed at the top or top of the indoor room.

[0048] Reference Figure 1 Taking an indoor wall mounted unit as an example, the indoor wall mounted unit is usually installed at a location such as an indoor wall. For another example, an indoor cabinet unit (not shown in the figure) is also a form of the indoor unit 11 .

[0049] Taking a split unit as an example, the air conditioner 100 includes an indoor unit 11 and an outdoor unit 14, wherein the outdoor unit 14 is usually arranged outdoors for heat exchange in the indoor environment.

[0050] In addition, if Figure 1As shown in the figure, the air conditioner 100 is provided with a controller 71 to control the operation of various components in the air conditioner 100, so that the various components of the air conditioner 100 operate to realize various predetermined functions of the air conditioner 100. Among them, the air conditioner 100 is also provided with a control device 200. Exemplarily, the control device 200 is specifically configured as a remote controller, and the remote controller has the function of communicating with the controller 71, for example, using infrared or other communication methods. The remote controller is used for the user to perform various controls on the air conditioner 100 and realize the interaction between the user and the air conditioner 100.

[0051] The indoor unit 11 of the air conditioner 100 in the embodiment of the present invention is arranged at the top or upper part of the room. Generally speaking, the installation height of the indoor unit 11 is higher than the user activity area. The indoor unit 11 includes a return air port 13 and an air outlet 12 connected to the room. The indoor air enters the indoor unit 11 through the return air port 13 and flows back to the room through the air outlet 12.

[0052] The refrigerant circulation loop 102 in the present invention allows the refrigerant to circulate in a loop consisting of a compressor, a condenser, an expansion valve, and an evaporator. One of the condenser and the evaporator is an outdoor heat exchanger, and the other is an indoor heat exchanger. The indoor heat exchanger is used to exchange heat with the air in the indoor unit 11, and the outdoor unit 14 heat exchanger is used to exchange heat with the air in the outdoor unit 14, thereby achieving the cooling or heating requirements of the air conditioner 100.

[0053] The indoor unit 11 also includes an indoor fan, which is arranged in the indoor heat exchanger near the return air port 13 or the air outlet 12 to deliver the heat-exchanged air to the room. The indoor fan includes multiple gears to change the air outlet speed of the air outlet 12.

[0054] An air guide plate 2 is provided at the position of the air outlet 12. The air guide plate 2 adjusts the outflow direction of the air flowing through the air outlet 12 by changing the relative rotation angle between the air guide plate 2 and the air outlet 12, thereby affecting the indoor air temperature stratification.

[0055] In the embodiment shown in the present invention, the air conditioner 100 further includes a controller 71, which refers to a device that can generate an operation control signal according to the instruction operation code and the timing signal to instruct the air conditioner 100 to execute the control instruction. For example, in response to a power-on or power-off instruction received from a user, the controller 71 can execute an operation related to the object selected by the power-on or power-off instruction.

[0056] The embodiment of the present invention also provides a hardware structure diagram of a controller 71, as shown in FIG. Figure 2 As shown, the controller 71 includes a processor 83, and optionally, further includes a memory 82 and a communication interface 84 connected to the processor 83. The processor 83, the memory 82 and the communication interface 84 are connected via a bus 81.

[0057] The processor 83 may be a central processing unit 83 (CPU), a general processor 83, a network processor 83 (NP), a digital signal processor 83 (DSP), a microprocessor 83, a microcontroller 83, a programmable logic device (PLD), or any combination thereof. The processor 83 may also be any other device having a processing function, such as a circuit, a device, or a software module. The processor 83 may also include multiple CPUs, and the processor 83 may be a single-CPU processor 83 or a multi-CPU processor 83. The processor 83 here may refer to one or more devices, circuits, or processing cores for processing data (such as computer program instructions).

[0058] The memory 82 may be a read-only memory 82 (ROM) or other types of static storage devices that can store static information and instructions, a random access memory 82 (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory 82 (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of an instruction or data structure and can be accessed by a computer, and the embodiment of the present invention does not impose any restrictions on this. The memory 82 may exist independently or be integrated with the processor 83. Among them, the memory 82 may contain a computer program code. The processor 83 is used to execute the computer program code stored in the memory 82, so as to realize the control method of the PFC circuit of the air conditioner provided in the embodiment of the present invention.

[0059] The communication interface 84 can be used to communicate with other devices or communication networks (such as Ethernet, radio access network (RAN), wireless local area networks (WLAN), etc. The communication interface 84 can be a module, a circuit, a transceiver or any device that can achieve communication.

[0060] The bus 81 may be a peripheral component interconnect (PCI) bus 81 or an extended industry standard architecture (EISA) bus 81, etc. The bus 81 may be divided into an address bus 81, a data bus 81, a control bus 81, etc. For ease of representation, Figure 1 Although only one thick line is used in the figure, it does not mean that there is only one bus 81 or only one type of bus 81.

[0061] Combine the following Figure 3-Figure 6 An air conditioner 100 according to an embodiment of the present invention is described.

[0062] like Figure 3 As shown, the air conditioner 100 of the embodiment of the present invention includes: a housing 101, a refrigerant circulation loop 102, a multi-channel PFC circuit 103, a temperature monitoring module 104 and a controller 71, wherein the multi-channel PFC circuit 103 is connected in parallel between the power input end and the power output end of the air conditioner, and the multi-channel PFC circuit 103 includes a plurality of parallel PFC channels for correcting the input current waveform of the air conditioner, wherein each PFC channel is provided with a switch element, and the switch element includes but is not limited to an IGBT (Insulated Gate Bipolar Transistor) switch tube; the temperature monitoring module 104 is used to monitor the temperature of the switch element of each PFC channel. In a specific embodiment, the temperature monitoring module 104 can be a temperature sensor or a calculation processor, and the calculation processor can calculate the temperature of each switch element according to the relevant operating parameters of each switch element in each PFC channel.

[0063] The controller 71 is configured to: after the multi-channel PFC circuit 103 is started, control each PFC channel to operate with the same current; obtain the temperature of the switch element of each PFC channel during the operation of each PFC channel with the same current; determine the average temperature value of the switch element in the multi-channel PFC circuit 103 according to the temperature of the switch element of each PFC channel; determine the target current distribution coefficient of each PFC channel according to the average temperature value; and adjust the current size of the corresponding PFC channel according to the target current distribution coefficient of each PFC channel, so that the temperature of the switch element of each PFC channel changes and finally remains consistent.

[0064] In the embodiment, after the multi-channel PFC circuit 103 is started, the controller 71 controls each PFC channel to operate with the same current, that is, current sharing control, to ensure that the current of each PFC channel of the multi-channel PFC circuit 103 remains balanced; when each PFC channel operates with the same current, the temperature monitoring module 104 is controlled to obtain the temperature value of the switch element of each PFC channel in real time, for example, recorded as Tn. After obtaining the temperature value Tn of the switch element in each PFC channel, the average temperature value of the switch element in the multi-channel PFC circuit 103 is calculated according to a preset algorithm, for example, recorded as Tavg, and the target current distribution coefficient of each PFC channel is adjusted in real time according to the average temperature value Tavg of the switch element, for example, recorded as Rn, so as to reasonably distribute the current value of each PFC channel according to the target current distribution coefficient Rn, and the current value of the corresponding PFC channel is adjusted in real time, for example, recorded as Iacn, and the on or off time of the switch element is controlled according to the current value Iacn of the corresponding PFC channel, so that the temperature value Tn of the switch element of each PFC channel changes until the temperature value Tn of the switch element is consistent, so as to achieve temperature balance control of the switch element of each PFC channel, avoid the multi-channel PFC circuit 103 being damaged due to the excessively high temperature value Tn of one or some switch elements, thereby improving the stability and reliability of the operation of the multi-channel PFC circuit 103.

[0065] According to the air conditioner 100 of the embodiment of the present invention, the average temperature value of the switching elements is obtained by monitoring the temperature of the switching elements, and the target current distribution coefficients of the corresponding PFC channels are determined. The current values ​​of the corresponding PFC channels are reasonably distributed according to the target current distribution coefficients, so that the temperature values ​​of the switching elements are adjusted according to the distributed current values, so that the actual temperature values ​​of the switching elements tend to be consistent. Therefore, by determining the target current distribution coefficients corresponding to the average temperature value of the switching elements, the current values ​​of the PFC channels are adjusted, and the temperature balance control of the switching elements of the multiple PFC channels is achieved, so that the damage of the multi-channel PFC circuit 103 caused by the excessive temperature of one or some switching elements is avoided, thereby improving the stability and reliability of the operation of the multi-channel PFC circuit 103.

[0066] In some embodiments, when adjusting the current size of the corresponding PFC channel according to the target current distribution coefficient of each PFC channel, the controller 71 is configured to: obtain a total current target value of the multi-channel PFC circuit 103; obtain the target current of the corresponding PFC channel according to the product of the total current target value and the target current distribution coefficient of each PFC channel, and adjust the current of each PFC channel to the corresponding target current, so as to adjust the current size of the corresponding PFC channel.

[0067] In an embodiment, when each PFC channel is operating at the same current, the controller 71 obtains the bus target voltage value of the multi-channel PFC circuit 103, for example, recorded as Vdc_ref and the actual voltage value, for example, recorded as Vdc, and calculates the voltage error between the target voltage value Vdc_ref and the actual voltage value Vdc. The voltage controller performs PI (proportional, integral) voltage control on the target voltage value Vdc_ref and the actual voltage value Vdc according to the voltage error to obtain the output current value, and calculates the product of the output current value and the absolute value of the power supply voltage value Vac, that is, |Vac|, and uses the product as the total current target value, for example, recorded as Iac_ref.

[0068] After obtaining the total current target value Iac_ref of the multi-channel PFC circuit 103, the product of the total current target value Iac_ref and the target current distribution coefficient Rn of the PFC channel is calculated respectively, and the target current value Iacn_ref of the corresponding PFC channel is obtained accordingly. The current difference between the target current value Iacn_ref and the actual current value Iac_ref is calculated respectively, and the current controller of each channel performs PI current control on the target current value Iacn_ref and the actual current value Iac_ref according to the current difference, and adjusts the current value of the PFC channel to the corresponding target current value. By determining the target current value Iacn_ref of each PFC channel, the current of the channel can be reasonably distributed according to the target current value Iacn_ref of each PFC channel.

[0069] by Figure 4 For example, the multi-channel PFC circuit 103 sets three PFC channels in parallel, and the target current distribution coefficients include R1, R2 and R3. The products of the total current target value Iac_ref and the target current distribution coefficients R1, R2 and R3 are calculated respectively, and the target current values ​​Iac1_ref, Iac2_ref and Iac3_ref of the corresponding PFC channels are obtained, that is, Iac1_ref=R1×Iac_ref, Iac2_ref=R2×Iac_ref, Iac3_ref=R3×Iac_ref. The current controller 1 is based on the current error Iac1_ref-Iac1 performs PI current control, and adjusts the current value Iac1 of the PFC channel in real time until it reaches the corresponding target current value Iac1_ref; current controller 2 performs PI current control according to the current error Iac2_ref-Iac2, and adjusts the current value Iac2 of the PFC channel in real time until it reaches the corresponding target current value Iac2_ref; current controller 3 performs PI current control according to the current error Iac3_ref-Iac3, and adjusts the current value Iac3 of the PFC channel in real time until it reaches the corresponding target current value Iac3_ref.

[0070] In some embodiments, when determining the current distribution coefficient of each PFC channel according to the average temperature value, the controller 71 is configured to: determine the initial current distribution coefficient of each PFC channel according to the average temperature value; and determine the target current distribution coefficient of each PFC channel according to the initial current distribution coefficient of each PFC channel.

[0071] In the embodiment, after the multi-channel PFC circuit 103 is started, the temperature monitoring module 104 acquires the temperature value Tn of the switch element of each PFC channel in real time, and calculates the average temperature value of the switch element in the multi-channel PFC circuit 103 according to a preset algorithm, for example, recorded as Tavg. Then, the initial current distribution coefficient of each PFC channel can be determined according to the average temperature value Tavg, that is, the current distribution coefficient corresponding to the current average temperature value Tavg of the switch element; the target current distribution coefficient of each PFC channel can be determined according to the initial current distribution coefficient of each PFC channel, that is, on the basis of the initial current distribution coefficient, the target current distribution coefficient of each PFC channel is obtained by a preset algorithm.

[0072] In some embodiments, when determining the initial current distribution coefficient of each PFC channel according to the average temperature value, the controller 71 is configured to: subtract the average temperature from the temperature of the switch element of each PFC channel, respectively, input the obtained difference values ​​into the temperature compensation controller for calculation, and then output the initial current distribution coefficient of each PFC channel respectively, wherein the temperature compensation controller is used to perform proportional integral logic operation on the input difference values.

[0073] In the embodiment, when determining the initial current distribution coefficient of each PFC channel according to the average temperature value Tavg, first, the controller 71 subtracts the average temperature from the temperature of the switch element of each PFC channel to obtain the difference, that is, the error between the switch element of each channel and the average temperature; then the obtained difference is respectively input into the temperature compensation controller for proportional integral logic operation, that is, after PI control, the difference is adjusted and optimized, so as to calculate the initial current distribution coefficient of each PFC channel.

[0074] like Figure 4 and Figure 5 FIG. 1 is a circuit diagram of an air conditioner according to an embodiment of the present invention. The air conditioner 100 is provided with a plurality of PFC channels in parallel. Figure 4 and Figure 5The example shown in the figure includes three PFC channels, each of which is provided with a switch element, for example, switch element 1, switch element 2 and switch element 3. After the controller 71 controls the three PFC channels to operate at the same current, the temperature value of switch element 1 monitored in real time by the temperature monitoring module 104 is obtained, for example, as T1, the temperature value of switch element 2 is for example, as T2, and the temperature value of switch element 3 is for example, as T3; then, the average temperature value Tavg of the switch element is calculated, that is, Tavg = (T1 + T2 + T3) / 3. The average temperature value Tavg is subtracted from the temperature values ​​T1, T2, and T3 of the switch elements of each PFC channel, and the difference is calculated by the temperature compensation controller, and the initial current distribution coefficients R_T1, R_T2, and R_T3 of each PFC channel are output respectively.

[0075] In some embodiments, when determining the target current distribution coefficient of each PFC channel according to the average temperature value, if the temperature of the switch element of the PFC channel is higher, the corresponding initial current distribution coefficient and target current distribution coefficient are smaller; if the temperature of the switch element of the PFC channel is lower, the corresponding initial current distribution coefficient and target current distribution coefficient are larger.

[0076] In an embodiment, when determining the target current distribution coefficient of each PFC channel according to the average temperature value, the initial current distribution coefficient and the target current distribution coefficient of each PFC channel can be adjusted in real time according to the temperature value of the switch element. If the temperature of the switch element of the PFC channel is higher, the corresponding initial current distribution coefficient and the target current distribution coefficient are lower, so as to reduce the current distribution and prevent the temperature of the switch element from being too high. If the temperature of the switch element of the PFC channel is lower, the corresponding initial current distribution coefficient and the target current distribution coefficient are higher, so as to increase the current distribution and increase the temperature of the switch element, so as to achieve the temperature balance of each switch element of the multiple PFC channels. That is, the temperature Tn of the switch element of each PFC channel is inversely proportional to the corresponding current distribution coefficient Rn.

[0077] In some embodiments, when determining the target current distribution coefficient of each PFC channel according to the initial current distribution coefficient of each PFC channel, the controller 71 is configured to: determine the current distribution coefficient of each PFC channel by the following formula, which includes:

[0078] Rn=(R_Tn+R_OFFSET) / (R_T1+…+R_TN+R_OFFSET×N);

[0079] Wherein, N is the number of PFC channels, N is an integer greater than 1, n is the current PFC channel, Rn is the target current distribution coefficient of PFC channel n, R_Tn is the initial current distribution coefficient of PFC channel n, n is a positive integer and n is less than or equal to N, and R_OFFSET is a preset coefficient compensation offset value.

[0080] In the embodiment, when determining the target current distribution coefficient of each PFC channel according to the initial current distribution coefficient of each PFC channel, the temperature value Tn of the switch element is substituted into the calculation formula of the target current distribution coefficient Rn=(R_Tn+R_OFFSET) / (R_T1+…+R_TN+R_OFFSET×N) to obtain the target current distribution coefficient Rn of the corresponding PFC channel. Figure 4 For example, the number of PFC channels is N=3, the temperature value of switch element 1 is T1, the temperature value of switch element 2 is T2, and the temperature value of switch element 3 is T3. The current distribution coefficient calculation formulas corresponding to each PFC channel are as follows:

[0081] R1=(R_T1+R_OFFSET) / (R_T1+R_T2+R_T3+R_OFFSET×3)

[0082] R2=(R_T2+R_OFFSET) / (R_T1+R_T2+R_T3+R_OFFSET×3)

[0083] R3=(R_T3+R_OFFSET) / (R_T1+R_T2+R_T3+R_OFFSET×3)

[0084] Among them, R_OFFSET is the compensation bias value. In order to avoid abnormal current distribution caused by the negative outputs R_T1, R_T2, and R_T3 of the switching element temperature compensation controller, the switching element temperature compensation controller and R_OFFSET can be reasonably designed to ensure that the current distribution coefficients R1, R2, and R3 are always positive.

[0085] In some embodiments, when controlling each PFC channel to operate with the same current, the controller 71 is configured to: divide the total current target value of the multi-channel PFC circuit 103 according to the number of PFC channels to obtain an equal current; and control each PFC channel to operate with the equal current.

[0086] In an embodiment, after the multi-channel PFC circuit 103 is started, when the controller 71 controls each PFC channel to operate with the same current, the controller 71 may determine the number of PFC channels, and evenly divide the total current target value Iac_ref of the multi-channel PFC circuit 103 according to the number of PFC channels to obtain an evenly divided current, thereby controlling each PFC channel to operate with the evenly divided current.

[0087] like Figure 4 and Figure 5 As shown, the number of PFC channels N=3, the total current target value Iac_ref of the multi-channel PFC circuit 103 is evenly divided to obtain an evenly divided current, ie, Iac1=Iac2=Iac3=Iac_ref / 3, and the three PFC channels are controlled to operate with the above evenly divided current.

[0088] In some embodiments, before determining the average temperature value of the switch elements in the multi-channel PFC circuit 103 according to the temperature of the switch elements of each PFC channel, the controller 71 is further configured to: determine whether the multi-channel PFC circuit 103 runs to a stable state; if it is determined that the multi-channel PFC circuit 103 runs to a stable state, perform an action of determining the average temperature value of the switch elements in the multi-channel PFC circuit 103 according to the temperature of the switch elements of each PFC channel; if it is determined that the multi-channel PFC circuit 103 does not run to a stable state, temporarily do not perform the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit 103 according to the temperature of the switch elements of each PFC channel, until the multi-channel PFC circuit 103 does not run to a stable state, then perform the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit 103 according to the temperature of the switch elements of each PFC channel.

[0089] In the embodiment, before determining the average temperature value of the switch elements in the multi-channel PFC circuit 103 according to the temperature of the switch elements of each PFC channel, it is first determined whether the multi-channel PFC circuit 103 runs to a stable state. If the multi-channel PFC circuit 103 runs to a stable state, an action of determining the average temperature value of the switch elements in the multi-channel PFC circuit 103 according to the temperature of the switch elements of each PFC channel is performed; if the multi-channel PFC circuit 103 does not run to a stable state, the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit 103 according to the temperature of the switch elements of each PFC channel is temporarily not performed until the multi-channel PFC circuit 103 does not run to a stable state, and then the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit 103 according to the temperature of the switch elements of each PFC channel is performed. Therefore, when the system is in a stable state, the detection result of the temperature parameter of each channel is ensured to be more accurate, and the result of the subsequent calculation of the current distribution coefficient is also made more accurate, which is conducive to more accurate adjustment of the current of each channel, so that the temperature control of the switch elements of each channel is more accurate, and the stability of the multi-channel PFC circuit 103 is fully guaranteed.

[0090] In some embodiments, when it is determined that the temperature of the switch element of each PFC channel is continuously and stably within a set temperature range within a set time period, it is determined that the multi-channel PFC circuit 103 has run to a stable state.

[0091] In the embodiment, since the temperature value Tn of the switching element usually changes very slowly, it is necessary to wait until the system runs stably before adjusting the target current distribution coefficient Rn. Therefore, whether the multi-channel PFC circuit 103 runs to a stable state is judged according to whether the temperature value Tn of the switching element is continuously stable within the set temperature range within the set time period. When the temperature value Tn of the switching element is continuously stable within the set temperature range within the set time period, it is considered that the temperature value Tn of the switching element is relatively stable, and it is determined that the multi-channel PFC circuit 103 has run to a stable state; when the temperature value Tn of the switching element is not continuously stable within the set temperature range within the set time period, it is considered that the temperature value Tn of the switching element changes greatly, and it is determined that the multi-channel PFC circuit 103 has not run to a stable state.

[0092] In some embodiments, when adjusting the current value of each PFC channel to its corresponding target current value, the controller 71 is further configured to: determine a PWM modulation pulse corresponding to the target current value of each PFC channel; and control the on or off time of the switching element according to the PWM modulation pulse to adjust the current value of each PFC channel.

[0093] In an embodiment, after the current controller of each channel performs PI current control on the target current value Iacn_ref and the actual current value Iac_ref according to the current difference, the current error output by the current controller of each channel is compensated according to the grid voltage Vac, for example, the current error output by the current controller of each channel is compensated according to the absolute value |Vac| of the grid voltage Vac and the compensation coefficient k, so as to determine the duty cycle of multiple channels, for example, recorded as dn, and after comparing the duty cycle dn of the multiple channels with the carrier, the corresponding PWM modulation pulse is determined, for example, recorded as PWMn, and the on or off time of the switching element is controlled according to the PWM modulation pulse PWMn, and the current value of the PFC channel is adjusted in real time, so as to achieve the consistency of the temperature value of each switching element of each PFC channel, thereby improving the reliability of the multi-channel PFC circuit 103.

[0094] by Figure 4 and Figure 5For example, the grid voltage Vac compensates the current error Iac1_ref-Iac1 output by the current controller 1, determines the corresponding duty cycle d1, and compares the duty cycle d1 with the carrier to determine the corresponding PWM modulation pulse PWM1. According to the on or off time of the switch element 1 controlled by PWM1, the current value Iac1 of the PFC channel is adjusted; the grid voltage Vac compensates the current error Iac2_ref-Iac2 output by the current controller 2, determines the corresponding duty cycle d2, and compares the duty cycle d2 with the carrier to determine the corresponding PWM modulation pulse PWM2. According to the on or off time of the switch element 2 controlled by PWM2, the current value Iac2 of the PFC channel is adjusted; the grid voltage Vac compensates the current error Iac3_ref-Iac3 output by the current controller 3, and the corresponding duty cycle is determined to be d3. After comparing the duty cycle d3 with the carrier, the corresponding PWM modulation pulse is determined to be PWM3. According to the on or off time of the switch element 3 controlled by PWM modulation pulse PWM3, the current value Iac3 of the PFC channel is adjusted to ensure that the temperature value T1 of the switch element 1, the temperature value T2 of the switch element 2 and the temperature value T3 of the switch element 3 are consistent.

[0095] Reference below Figure 6 The control method of the air conditioner according to the embodiment of the present invention is described by way of example.

[0096] like Figure 6 As shown, the air conditioner control method according to the embodiment of the present invention at least includes steps S11 to S25.

[0097] Step S11, the multi-channel PFC circuit is started.

[0098] Step S12, dividing the total current target value of the multi-channel PFC circuit according to the number of PFC channels to obtain an evenly distributed current; and controlling each PFC channel to operate with the evenly distributed current.

[0099] Step S13, obtaining the temperature value of the switch element in each PFC channel.

[0100] Step S14, determining an average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature value of the switch elements of each PFC channel.

[0101] Step S15: If the temperature of the switch element of the PFC channel is higher, the corresponding initial current distribution coefficient and target current distribution coefficient are smaller.

[0102] Step S16: If the temperature of the switch element of the PFC channel is smaller, the corresponding initial current distribution coefficient and target current distribution coefficient are larger.

[0103] Step S17, determining whether the temperature value of the switch element is continuously and stably within the set temperature range within the set time period, if so, executing step S18; otherwise, executing step S19.

[0104] Step S18, determining that the multi-channel PFC circuit has run to a stable state.

[0105] Step S19: the multi-channel PFC circuit does not run to a stable state.

[0106] Step S20 , temporarily not performing the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each PFC channel.

[0107] Step S21 , determining an average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements in each PFC channel.

[0108] Step S22, obtaining a total current target value of the multi-channel PFC circuit.

[0109] Step S23, calculating the product of the total current target value and the target current distribution coefficient of the PFC channel, and obtaining the target current value of the corresponding PFC channel.

[0110] Step S24, determining the PWM modulation pulse corresponding to the target current value of each PFC channel.

[0111] Step S25, controlling the on or off time of the switch element according to the PWM modulation pulse to adjust the current value of the PFC channel.

[0112] According to the air conditioner 100 of the embodiment of the present invention, by monitoring the temperature of the switching element, an average temperature value of the switching element is obtained, and a target current distribution coefficient of each PFC channel corresponding thereto is determined, and the current value of the corresponding PFC channel is reasonably distributed according to the target current distribution coefficient, so that the temperature value of the switching element is adjusted according to the distributed current value, so that the actual temperature value of the switching element tends to be consistent. Therefore, by determining the target current distribution coefficient corresponding to the average temperature value of the switching element and adjusting the current value of the PFC channel, the temperature balance control of the switching elements of multiple PFC channels can be achieved, so that the temperature of each switching element is kept consistent, and the situation that the temperature of one or some switching elements is too high, causing damage to the PFC circuit, is avoided, and the operation stability and reliability of the PFC circuit are improved.

[0113] Combine the following Figure 7 The control method of the air conditioner according to the embodiment of the present invention is described by way of example. The control method of the air conditioner can be used for the air conditioner described in any one of the above embodiments of the present invention.

[0114] like Figure 7As shown, the air conditioner control method according to the embodiment of the present invention at least includes steps S1 to S5.

[0115] Step S1, after the multi-channel PFC circuit of the air conditioner is started, each PFC channel in the multi-channel PFC circuit is controlled to operate with the same current, wherein the multi-channel PFC circuit includes a plurality of parallel PFC channels, and each PFC channel is provided with a switch element.

[0116] In an embodiment, after the multi-channel PFC circuit is started, the multiple PFC channels are controlled to operate with the same current, that is, current sharing control is performed to ensure that the currents of the multiple PFC channels of the multi-channel PFC circuit remain balanced.

[0117] Step S2: when each PFC channel is running at the same current, obtaining the temperature of the switch element of each PFC channel.

[0118] In an embodiment, when each PFC channel is running at the same current, the temperature monitoring module is controlled to monitor the temperature of the switch element in each PFC channel in real time, for example, recorded as Tn.

[0119] Step S3, determining an average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each PFC channel.

[0120] In an embodiment, after the temperature Tn of the switch element in the PFC channel is obtained, the average temperature value of the switch element in the multi-channel PFC circuit may be calculated and recorded as Tavg, for example.

[0121] Step S4, determining the target current distribution coefficient of each PFC channel according to the average temperature value.

[0122] In an embodiment, after determining the average temperature value Tavg of the switch elements in each PFC channel, the target current distribution coefficient of the multiple PFC channels is adjusted in real time according to the average temperature value Tavg, for example, recorded as Rn, so as to reasonably distribute the current values ​​of the multiple PFC channels according to the target current distribution coefficient Rn.

[0123] Step S5: adjusting the current of the corresponding PFC channel according to the target current distribution coefficient of each PFC channel, so that the temperature of the switch element of each PFC channel changes and finally remains consistent.

[0124] In the embodiment, after the target current distribution coefficient Rn is determined, the current value of the corresponding PFC channel is adjusted in real time according to the target current distribution coefficient Rn, for example, recorded as Iacn, and the on or off time of the switch element is controlled according to the current value Iacn of the corresponding PFC channel, so as to adjust the current size of the corresponding PFC channel accordingly, so that the temperature of the switch element of each PFC channel changes and finally remains consistent, so as to achieve temperature balance control of the switch element of each PFC channel, avoid damage to the multi-channel PFC circuit due to excessive temperature of one or some switch elements, and thus improve the stability and reliability of the operation of the multi-channel PFC circuit.

[0125] It should be noted that when controlling the air conditioner, the specific implementation method of the control method of the air conditioner is similar to the specific implementation method of the above-mentioned air conditioner of the present invention. Therefore, for a detailed exemplary description of the control method of the air conditioner, please refer to the aforementioned description of the air conditioner. In order to reduce redundancy, it will not be repeated here.

[0126] According to the control method of the air conditioner of the embodiment of the present invention, by monitoring the temperature of the switching element, an average temperature value of the switching element is obtained, and the target current distribution coefficient of each PFC channel corresponding thereto is determined, and the current value of the corresponding PFC channel is reasonably distributed according to the target current distribution coefficient, so that the temperature value of the switching element is adjusted according to the distributed current value, so that the actual temperature value of the switching element tends to be consistent. Therefore, by determining the target current distribution coefficient corresponding to the average temperature value of the switching element and adjusting the current value of the PFC channel, the temperature balance control of the switching elements of multiple PFC channels can be achieved, so that the temperature of each switching element is kept consistent, and the situation that the temperature of one or some switching elements is too high, causing damage to the PFC circuit, is avoided, and the operation stability and reliability of the PFC circuit are improved.

[0127] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0128] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An air conditioner, characterized in that: include: chassis; A refrigerant circulation loop, wherein the refrigerant performs a refrigeration cycle in a loop consisting of a compressor, a condenser, an electronic expansion valve, and an evaporator, wherein one of the condenser and the evaporator is an outdoor heat exchanger and the other is an indoor heat exchanger; a multi-channel PFC circuit connected in parallel between a power input terminal and a power output terminal of the air conditioner, wherein the multi-channel PFC circuit comprises a plurality of parallel PFC channels for correcting an input current waveform of the air conditioner; Wherein, each of the PFC channels is provided with a switch element; A temperature monitoring module, used to monitor the temperature of the switch element of each PFC channel; The controller is configured as: After the multi-channel PFC circuit is started, controlling each of the PFC channels to operate with the same current; When each of the PFC channels is operated at the same current, obtaining the temperature of the switch element of each of the PFC channels; Determining an average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each of the PFC channels; Determine a target current distribution coefficient for each of the PFC channels according to the average temperature value; The current magnitude of the corresponding PFC channel is adjusted accordingly according to the target current distribution coefficient adjustment of each PFC channel, so that the temperature of the switch element of each PFC channel changes and finally remains the same.

2. The air conditioner according to claim 1, characterized in that: When the current magnitude of the corresponding PFC channel is adjusted according to the target current distribution coefficient of each PFC channel, the controller is configured as follows: Obtaining a total current target value of the multi-channel PFC circuit; Calculating the product of the total current target value and the target current distribution coefficient of each of the PFC channels to obtain target current values ​​of the corresponding PFC channels respectively; The current of each of the PFC channels is adjusted to the corresponding target current, so as to adjust the current magnitude of the corresponding PFC channel.

3. The air conditioner according to claim 1, characterized in that: When determining the current distribution coefficient of each of the PFC channels according to the average temperature value, the controller is configured to: Determining an initial current distribution coefficient of each of the PFC channels according to the average temperature value; The target current distribution coefficient of each PFC channel is correspondingly determined according to the initial current distribution coefficient of each PFC channel.

4. The air conditioner according to claim 3, characterized in that: When determining the initial current distribution coefficient of each of the PFC channels according to the average temperature value, the controller is configured to: The average temperature is subtracted from the temperature of the switch element of each PFC channel, and the obtained differences are input into the temperature compensation controller for calculation, and then the initial current distribution coefficients of each PFC channel are outputted respectively, wherein the temperature compensation controller is used to perform proportional integral logic operation on the input differences.

5. The air conditioner according to claim 4, characterized in that: When determining the target current distribution coefficient of each of the PFC channels according to the average temperature value, if the temperature of the switch element of the PFC channel is higher, the corresponding initial current distribution coefficient and the target current distribution coefficient are lower; if the temperature of the switch element of the PFC channel is lower, the corresponding initial current distribution coefficient and the target current distribution coefficient are higher.

6. The air conditioner according to claim 3, characterized in that: When determining the target current distribution coefficient of each PFC channel according to the initial current distribution coefficient of each PFC channel, the controller is configured to: determine the current distribution coefficient of each PFC channel by the following formula, wherein the formula includes: Rn=(R_Tn+R_OFFSET) / (R_T1+…+R_TN+R_OFFSET×N); Among them, N is the number of the PFC channels, N is an integer greater than 1, n is the current PFC channel, Rn is the target current distribution coefficient of PFC channel n, R_Tn is the initial current distribution coefficient of PFC channel n, n is a positive integer and n is less than or equal to N, and R_OFFSET is a preset coefficient compensation offset value.

7. The air conditioner according to claim 2, characterized in that: When controlling each of the PFC channels to operate at the same current, the controller is configured as follows: Dividing the total current target value of the multi-channel PFC circuit equally according to the number of the PFC channels to obtain an equally divided current; Each of the PFC channels is controlled to operate with the shared current.

8. The air conditioner according to claim 1, characterized in that: Before determining the average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each of the PFC channels, the controller is further configured to: Determining whether the multi-channel PFC circuit operates to a stable state; If it is determined that the multi-channel PFC circuit runs to a stable state, an action of determining an average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each of the PFC channels is performed; If it is determined that the multi-channel PFC circuit has not run to a stable state, the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements in each of the PFC channels is temporarily not performed, until the multi-channel PFC circuit has not run to a stable state, the action of determining the average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements in each of the PFC channels is performed again.

9. The air conditioner according to claim 8, characterized in that: The controller is specifically configured as follows: When it is determined that the temperature of the switch element of each of the PFC channels is continuously and stably within the set temperature range within the set time period, it is determined that the multi-channel PFC circuit has run to a stable state.

10. A method for controlling an air conditioner, characterized in that: The following steps are involved: After the multi-channel PFC circuit of the air conditioner is started, controlling each PFC channel in the multi-channel PFC circuit to operate with the same current, wherein the multi-channel PFC circuit includes a plurality of parallel PFC channels, each of which is provided with a switch element; When each of the PFC channels is operated at the same current, obtaining the temperature of the switch element of each of the PFC channels; Determining an average temperature value of the switch elements in the multi-channel PFC circuit according to the temperature of the switch elements of each of the PFC channels; Determine a target current distribution coefficient for each of the PFC channels according to the average temperature value; The current magnitude of the corresponding PFC channel is correspondingly adjusted according to the target current distribution coefficient of each PFC channel, so that the temperature of the switch element of each PFC channel changes and finally remains consistent.

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