Interleaved pfc circuit branch equalization control method, device and circuit and air conditioner

Abstract

The application discloses a kind of staggered PFC circuit branch equalization control method, device and circuit and air conditioner, belong to PFC circuit control field;After obtaining the branch current and dry way current of PFC circuit, according to each branch current and dry way current generation each branch IGBT control signal, then according to control signal control each branch IGBT's on-off, to make each branch current same;The target of each branch current is set to same value and is adjusted, so when generating IGBT control signal, it can guarantee that each branch IGBT current is same.Due to the scheme of the application directly according to each branch current is adjusted, so even if the component electrical parameter deviation of each branch is larger, the current obtained by final adjustment is also same, and the branch current deviation of large current does not cause the safe value that IGBT bears to be exceeded and then damage IGBT, while ensuring the normal work of PFC circuit, each branch IGBT can be protected, and the service life of IGBT is prolonged.

Description

Technical Field

[0001] This invention relates to the field of PFC circuit control, and in particular to an interleaved PFC circuit branch equalization control method, device, circuit, and air conditioner. Background Technology

[0002] The control principle of conventional interleaved PFC circuits is as follows: Figure 1 When the electrical parameters of the components in each branch of the PFC deviate by more than 5%, the current deviation of the branch IGBT exceeds 10%, and the IGBT current between branches is unbalanced. This results in the current value of the branch with large current deviation exceeding the safe value that the IGBT can withstand, damaging the IGBT module of that branch, and the air conditioning unit cannot work normally. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention provides an interleaved PFC circuit branch equalization control method, device, circuit and air conditioner to solve the problem of large branch current deviation in existing PFC circuits, which easily damages the branch IGBT modules.

[0004] The technical solution adopted by this invention to solve its technical problem is:

[0005] Firstly, a branch equalization control method for an interleaved PFC circuit is provided, comprising the following steps:

[0006] Obtain the current in each branch and the main circuit of the PFC circuit;

[0007] The control signals for each branch IGBT are generated based on the current of each branch and the current of the main circuit.

[0008] The control signal is used to control the switching on and off of the IGBTs in each branch so that the current in each branch is the same.

[0009] Furthermore, the step of generating control signals for each branch IGBT based on the branch current and the main circuit current includes:

[0010] Obtain the input voltage, output voltage, and given voltage of the main circuit of the PFC circuit;

[0011] The target main circuit current is obtained based on the input voltage, output voltage, and given voltage;

[0012] The trunk current is PID-regulated according to the target trunk current to obtain the trunk voltage; and the adjusted voltage of each branch is obtained according to the target trunk current and the current of each branch.

[0013] The control signals for each branch IGBT are obtained by adding the regulating voltage of each branch to the main voltage and then performing pulse width modulation.

[0014] Further, obtaining the target main circuit current based on the input voltage, output voltage, and given voltage includes:

[0015] The target output voltage is obtained by performing PID regulation on the output voltage based on the given voltage.

[0016] The target output voltage and the output voltage are input into a multiplier to obtain the target main circuit current.

[0017] Further, the step of obtaining the regulating voltage of each branch based on the target main circuit current and the current of each branch includes:

[0018] Divide the target main current by the number of branches to obtain the target branch current;

[0019] The regulated current of each branch is obtained by PID regulation of the current of each branch based on the target branch current;

[0020] The regulating voltage of each branch is obtained based on the regulating current of each branch.

[0021] Further, obtaining the regulating voltage of each branch based on the regulating current of each branch includes:

[0022] Obtain the inductive reactance, impedance, and duty cycle of the branch;

[0023] The formula for calculating the regulating voltage is: Where △uvx is the regulating voltage, Udc is the output voltage, d is the duty cycle, L is the inductive reactance of the branch, r is the impedance of the branch, △ivx is the regulating current, and x is the branch identifier.

[0024] Further, the step of dividing the target trunk current by the number of branches to obtain the target branch current includes:

[0025] Get the number of branches that are currently functioning normally in real time;

[0026] The target branch current is obtained by dividing the target main current by the number of branches that can operate normally.

[0027] Secondly, an interleaved PFC circuit branch equalization control device is provided, comprising:

[0028] A parameter acquisition module is used to acquire the parameters of the PFC circuit;

[0029] The signal generation module is used to generate control signals for each branch IGBT according to the parameters.

[0030] The IGBT control module is used to control the on / off state of each branch IGBT according to the control signal so that the current in each branch is the same.

[0031] Thirdly, an interleaved PFC circuit is provided, comprising: a modulation module and at least two branches, wherein any two branches are connected in parallel;

[0032] Each branch includes an inductor, a freewheeling diode, and an IGBT;

[0033] The modulation module is connected to the IGBTs of each branch and is used to control the on / off state of the IGBTs according to any one of the technical solutions provided in the first aspect.

[0034] Furthermore, it also includes: a current sampling and conditioning module, wherein the current sampling and conditioning module is respectively located on each branch, or the current sampling and conditioning module is respectively located on the main circuit and at least n-1 branches, where n is the total number of all branches.

[0035] Furthermore, the current sampling conditioning module includes a sampling resistor and an amplifier;

[0036] One end of the sampling resistor is connected to the non-inverting input of the amplifier through a resistor, and the other end is connected to the inverting input of the amplifier through another resistor. The output of the amplifier is connected to the modulation module, and the output of the amplifier is also connected to the inverting input of the amplifier through a feedback resistor.

[0037] Fourthly, an air conditioner is provided, comprising the circuit described in any one of the technical solutions provided in the third aspect.

[0038] Beneficial effects:

[0039] This invention provides a method, apparatus, circuit, and air conditioner for balanced branch control of an interleaved PFC circuit. After acquiring the current of each branch and the main circuit of the PFC circuit, control signals are generated for each branch's IGBT based on these currents. The on / off state of each branch's IGBT is then controlled according to these control signals to ensure that the current in each branch is the same. Since the on / off state of each branch's IGBT can change the voltage of that branch, thus affecting the current flowing through it, the target current for each branch is set to be the same for adjustment. This ensures that the IGBT current in each branch is the same when generating the IGBT control signal. Because this solution directly adjusts based on the current of each branch, even if the electrical parameters of the components in each branch deviate significantly, the final adjusted current will be the same. This prevents the current from exceeding the safe value that the IGBT can withstand due to large deviations in branch current, thus avoiding damage to the IGBT. While ensuring the normal operation of the PFC circuit, this method protects the IGBTs in each branch and extends their service life. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of a conventional interleaved PFC circuit control principle structure provided by an embodiment of the present invention;

[0042] Figure 2 This is a flowchart of an interleaved PFC circuit branch equalization control method provided in an embodiment of the present invention;

[0043] Figure 3 This is a diagram of a three-way parallel interleaved PFC circuit structure provided in an embodiment of the present invention;

[0044] Figure 4 This is provided by the embodiments of the present invention. Figure 3 The circuit diagram shown illustrates the principle of balanced control for each branch.

[0045] Figure 5 This is a schematic diagram of an interleaved PFC circuit branch equalization control device provided in an embodiment of the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of the present invention will be described in detail below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0047] The first embodiment, referred to Figure 2 This invention provides a branch equalization control method for an interleaved PFC circuit, comprising the following steps:

[0048] S11: Obtain the current in each branch and the main circuit of the PFC circuit;

[0049] S12: Generate control signals for each branch IGBT based on the current in each branch and the current in the main circuit.

[0050] S13: Control the on / off state of each branch IGBT according to the control signal to make the current in each branch the same.

[0051] The interleaved PFC circuit branch balancing control method provided in this invention obtains the current of each branch and the main circuit of the PFC circuit, generates control signals for each branch's IGBT based on these currents, and then controls the on / off state of each branch's IGBT according to the control signals to ensure that the current in each branch is the same. Since the on / off state of each branch's IGBT can change the voltage of that branch, thereby affecting the current flowing through that branch, setting the target current of each branch to the same value for adjustment ensures that the IGBT current in each branch is the same when generating the IGBT control signal. Because this embodiment of the invention directly adjusts based on the current of each branch, even if the electrical parameters of the components in each branch deviate significantly, the final adjusted current will be the same. This prevents the current from exceeding the safe value that the IGBT can withstand due to large deviations in the branch current, thus avoiding damage to the IGBT. While ensuring the normal operation of the PFC circuit, it can protect the IGBTs in each branch and extend the service life of the IGBTs.

[0052] The second embodiment is as follows: Figure 3 Taking the interleaved PFC circuit shown as an example, the branch balancing control method of the PFC circuit will be explained in detail. Figure 3 The PFC circuit shown consists of a rectifier bridge DB, an electrolytic capacitor C, resistors R4, R5, R6, and R7, and a sampling resistor R0. One end of R0 is grounded and connected to the non-inverting input of the third amplifier through resistor R01. The other end of resistor R0 is connected to the inverting input of the third amplifier through resistor R00. The non-inverting input of the third amplifier is grounded through resistor R03. The output of the third amplifier is connected to the modulation module DSP (i.e., the modulation module is actually a DSP chip). The output of the third amplifier is also connected to the inverting input of the third amplifier through feedback resistor R02.

[0053] The first branch includes a first inductor L1, a first IGBT module IGBT1, and a first freewheeling diode D1. The second branch includes a second inductor L2, a second IGBT module IGBT2, and a second freewheeling diode D2. IGBT2 is connected to a sampling resistor R2. One end of R2 connected to IGBT2 is connected to the inverting input of the first amplifier through a resistor R20. The other end of R2 is connected to the non-inverting input of the first amplifier through a resistor R21. The output of the first amplifier is connected to a modulation module DSP (i.e., the modulation module is actually a DSP chip). The output of the first amplifier is also connected to the inverting input of the first amplifier through a feedback resistor R22. The non-inverting input of the first amplifier is also grounded through a resistor R23. The third branch includes the third inductor L3, the third IGBT module IGBT3, the third freewheeling diode D3, and IGBT3 connected to sampling resistor R3. One end of R3 connected to IGBT3 is connected to the inverting input of the second amplifier through resistor R30, and the other end of R3 is connected to the non-inverting input of the first amplifier through resistor R31. The output of the second amplifier is connected to the modulation module DSP (i.e., the modulation module is actually a DSP chip). The output of the second amplifier is also connected to the inverting input of the second amplifier through feedback resistor R32. The non-inverting input of the second amplifier is also grounded through resistor R33. The first, second, and third branches are connected in parallel in the main circuit to achieve real-time power factor correction and current harmonic suppression for each branch.

[0054] The specific control process is as follows: Figure 4 As shown, given voltage U DCref With sampling voltage U DC The phase difference, after PID adjustment, yields the target output voltage Uvea, which is then compared with the sampled input voltage U. IN Multiplication essentially involves multiplying the target output voltage by the phase parameter of the input voltage to obtain the target main circuit current iLref. This target main circuit current iLref is then used in PID control with the main circuit current Iv0 to obtain the main circuit voltage Ucea. Simultaneously, 1 / 3 of the target main circuit current iLref is used as the target branch current, and it is multiplied by the sampling current I of each branch circuit. V1 I V2 I V3 The phase difference is adjusted by PID control to obtain the voltage Δi of each branch. V1 ,Δi V2 ,Δi V3 ΔU is obtained according to the following formula. V1 ,ΔU V2 ,ΔU V3 , Where △u vx To adjust the voltage, Udc is the output voltage, d is the duty cycle, L is the inductive reactance of the branch, r is the impedance of the branch, and Δi vxTo adjust the current, x is 1, 2, or 3.

[0055] ΔU V1 ,ΔU V2 ,ΔU V3 Then, it is added to the main circuit voltage Ucea respectively, and SPWM modulation is performed to generate the corresponding PWM for each branch, which controls the corresponding IGBT.

[0056] The control method provided in this embodiment of the invention further includes real-time acquisition of the number of branches currently operating normally; and dividing the target main circuit current by the number of branches operating normally to obtain the target branch current. That is, when a branch is open due to a fault, the target branch current is calculated based on the actual number of branches operating normally, such as... Figure 3 If the second branch fails, the target branch current will be equal to half of the target main branch current. This ensures that even if one branch fails, the current in the remaining branches will remain balanced.

[0057] The control method provided in this invention ensures that when the electrical parameters of the components in each branch of the PFC deviate significantly, the IGBT current in each branch is still evenly distributed, thereby reducing the selection values ​​of IGBTs, inductors, and diodes and lowering the design cost of key materials. At the same time, even if an IGBT in one branch fails, the other branches can still operate normally in a balanced manner, achieving fault backup without stopping the machine and improving equipment reliability.

[0058] In a third embodiment, the present invention provides an interleaved PFC circuit branch equalization control device, such as... Figure 5 As shown, it includes:

[0059] The parameter acquisition module 51 is used to acquire the current of each branch and the main current of the PFC circuit; the parameter acquisition module 51 is also used to acquire the input voltage, output voltage and given voltage of the main circuit of the PFC circuit.

[0060] The signal generation module 52 is used to generate control signals for each branch IGBT based on the current of each branch and the current of the main circuit. Specifically, the signal generation module 52 obtains the target main circuit current based on the input voltage, output voltage and given voltage; performs PID regulation on the main circuit current based on the target main circuit current to obtain the main circuit voltage; and obtains the regulating voltage of each branch based on the target main circuit current and the current of each branch; and adds the regulating voltage of each branch to the main circuit voltage and performs pulse width modulation to obtain the control signal of each branch IGBT.

[0061] The process of obtaining the target main circuit current based on the input voltage, output voltage, and given voltage includes: performing PID regulation on the output voltage based on the given voltage to obtain the target output voltage; and inputting the target output voltage and the given output voltage into a multiplier to obtain the target main circuit current.

[0062] Further, the regulating voltage of each branch is obtained based on the target main circuit current and the current of each branch, including: dividing the target main circuit current by the number of branches to obtain the target branch current; performing PID regulation on the current of each branch based on the target branch current to obtain the regulating current of each branch; and obtaining the regulating voltage of each branch based on the regulating current of each branch. Specifically, the inductive reactance, impedance, and duty cycle of the branch are obtained; the formula for calculating the regulating voltage is: Where △u vx To adjust the voltage, Udc is the output voltage, d is the duty cycle, L is the inductive reactance of the branch, r is the impedance of the branch, and Δi vx To adjust the current, x is the branch identifier.

[0063] As an optional implementation of this invention, the target branch current is obtained by dividing the target trunk current by the number of branches, including: real-time acquisition of the number of branches that are currently functioning normally; and dividing the target trunk current by the number of branches that are functioning normally to obtain the target branch current.

[0064] IGBT control module 53 is used to control the on / off state of each branch IGBT according to the control signal so that the current in each branch is the same.

[0065] The interleaved PFC circuit branch balancing control device provided in this embodiment of the invention comprises a parameter acquisition module that acquires the current of each branch and the main circuit current of the PFC circuit; a signal generation module that generates control signals for each branch IGBT based on the current of each branch and the main circuit current; and an IGBT control module that controls the on / off state of each branch IGBT based on the control signals to ensure that the current of each branch is the same. The device provided in this embodiment of the invention adjusts the target current of each branch to the same value, thus ensuring that the current of each branch IGBT is the same when generating the IGBT control signal. Because the solution in this embodiment of the invention directly adjusts based on the current of each branch, even if the electrical parameters of the components in each branch deviate significantly, the final adjusted current will be the same. This prevents the current of branches with large deviations from exceeding the safe value that the IGBT can withstand, thereby damaging the IGBT. While ensuring the normal operation of the PFC circuit, it can protect the IGBTs of each branch and extend the service life of the IGBTs.

[0066] In a fourth embodiment, the present invention provides an interleaved PFC circuit, such as... Figure 3 As shown, it includes: a modulation module and at least two branches, with any two branches connected in parallel;

[0067] Each branch includes an inductor, a freewheeling diode, and an IGBT;

[0068] The modulation module is connected to the IGBTs of each branch and is used to control the on / off state of the IGBTs according to the method provided in the first embodiment or the second embodiment.

[0069] It also includes: a current sampling and conditioning module, which is installed on each branch, or the current sampling and conditioning module is installed on the main circuit and at least n-1 branches, where n is the total number of all branches. Figure 3 The medium current sampling and conditioning module is set on the main circuit and two branches. Understandably, since the main circuit current equals the sum of the branch currents, it can also be set on only three branches. Of course, it can also be set on both the main circuit and the branches.

[0070] The current sampling and conditioning module includes a sampling resistor and an amplifier;

[0071] One end of the sampling resistor is connected to the non-inverting input of the amplifier through a resistor, and the other end is connected to the inverting input of the amplifier through another resistor. The output of the amplifier is connected to the modulation module, and the output of the amplifier is also connected to the inverting input of the amplifier through a feedback resistor.

[0072] Specifically, such as Figure 3 As shown, the current sampling and conditioning module on the main line includes a sampling resistor R0. One end of R0 is grounded and connected to the non-inverting input of the third amplifier through a resistor R01. The other end of the resistor R0 is connected to the inverting input of the third amplifier through a resistor R00. The non-inverting input of the third amplifier is grounded through a resistor R03. The output of the third amplifier is connected to the modulation module DSP (i.e., the modulation module is actually a DSP chip). The output of the third amplifier is also connected to the inverting input of the third amplifier through a feedback resistor R02.

[0073] The current sampling and conditioning module of the second branch includes a sampling resistor R2. One end of R2 is connected to the IGBT2 and then to the inverting input of the first amplifier through a resistor R20. The other end of R2 is connected to the non-inverting input of the first amplifier through a resistor R21. The output of the first amplifier is connected to the modulation module DSP (i.e., the modulation module is actually a DSP chip). The output of the first amplifier is also connected to the inverting input of the first amplifier through a feedback resistor R22. The non-inverting input of the first amplifier is also grounded through a resistor R23.

[0074] The current sampling and conditioning module of the third branch includes a sampling resistor R3. One end of R3, connected to the IGBT3, is connected to the inverting input of the second amplifier via resistor R30. The other end of R3 is connected to the non-inverting input of the first amplifier via resistor R31. The output of the second amplifier is connected to the modulation module DSP (i.e., the modulation module is actually a DSP chip). The output of the second amplifier is also connected to the inverting input of the second amplifier via feedback resistor R32. The non-inverting input of the second amplifier is grounded via resistor R33.

[0075] The PFC circuit provided in this embodiment of the invention, after acquiring the current of each branch and the main circuit of the PFC circuit, generates control signals for each branch's IGBT based on the branch and main circuit currents. Then, it controls the on / off state of each branch's IGBT according to the control signals to ensure that the current of each branch is the same. The target value of each branch's current is set to be the same for adjustment, thus ensuring that the IGBT current of each branch is the same when generating the IGBT control signal. Because this application's solution directly adjusts based on the current of each branch, even if the electrical parameters of the components in each branch deviate significantly, the final adjusted current will be the same. This prevents the current from exceeding the safe value that the IGBT can withstand due to large branch current deviations, thereby preventing damage to the IGBT. While ensuring the normal operation of the PFC circuit, it can protect the IGBTs of each branch and extend the service life of the IGBTs.

[0076] In the fifth embodiment, the present invention provides an air conditioner including the interleaved PFC circuit provided in the fourth embodiment. By using the interleaved PFC circuit provided in the embodiments of the present invention, when the electrical parameters of the components in each branch of the PFC are significantly different, the IGBT current between the branches is still evenly distributed, thereby reducing the selection values ​​of IGBTs, inductors, and diodes and lowering the design cost of key materials. Even if an IGBT in one branch fails, the other two branches can still operate normally in an even manner, realizing the air conditioning unit fault backup without shutting down, reducing the probability of air conditioning fault protection shutdown, and improving the reliability of the unit.

[0077] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.

[0078] It should be noted that in the description of this application, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this application, unless otherwise stated, "a plurality of" means at least two.

[0079] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the function involved, as will be understood by those skilled in the art to which embodiments of this application pertain.

[0080] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0081] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0082] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0083] The storage media mentioned above can be read-only memory, disk, or optical disk, etc.

[0084] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0085] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A branch equalization control method for an interleaved PFC circuit, characterized in that, Includes the following steps: Obtain the current in each branch and the main circuit of the PFC circuit; The control signals for each branch IGBT are generated based on the current of each branch and the current of the main circuit. The step of generating control signals for each branch IGBT based on the branch current and the main circuit current includes: Obtain the input voltage, output voltage, and given voltage of the main circuit of the PFC circuit; The target main circuit current is obtained based on the input voltage, output voltage, and given voltage; The trunk current is PID-regulated according to the target trunk current to obtain the trunk voltage; and the adjusted voltage of each branch is obtained according to the target trunk current and the current of each branch. The step of obtaining the regulating voltage of each branch based on the target main current and the current of each branch includes: Divide the target main current by the number of branches to obtain the target branch current; The step of dividing the target trunk current by the number of branches to obtain the target branch current includes: Get the number of branches that are currently functioning normally in real time; The target branch current is obtained by dividing the target main circuit current by the number of branches that can operate normally. The regulated current of each branch is obtained by PID regulation of the current of each branch based on the target branch current; The regulating voltage of each branch is obtained based on the regulating current of each branch; The control signals for each branch IGBT are obtained by adding the regulating voltage of each branch to the main voltage and then performing pulse width modulation. The control signal is used to control the switching on and off of the IGBTs in each branch so that the current in each branch is the same.

2. The method according to claim 1, characterized in that: The step of obtaining the target main circuit current based on the input voltage, output voltage, and given voltage includes: The target output voltage is obtained by performing PID regulation on the output voltage based on the given voltage. The target output voltage and the output voltage are input into a multiplier to obtain the target main circuit current.

3. The method according to claim 2, characterized in that: The step of obtaining the regulating voltage of each branch based on the regulating current of each branch includes: Obtain the inductive reactance, impedance, and duty cycle of the branch; The formula for calculating the regulating voltage is: △ =Udc (1-d)+L -r△ ;where △ To adjust the voltage, Udc is the output voltage, d is the duty cycle, L is the inductive reactance of the branch, r is the impedance of the branch, and Δ To adjust the current, x is the branch identifier.

4. A staggered PFC circuit branch equalization control device, characterized in that, include: The parameter acquisition module is used to acquire the current of each branch and the main current of the PFC circuit. The signal generation module is used to generate control signals for each branch IGBT based on the current of each branch and the current of the main circuit. The step of generating control signals for each branch IGBT based on the branch current and the main circuit current includes: Obtain the input voltage, output voltage, and given voltage of the main circuit of the PFC circuit; The target main circuit current is obtained based on the input voltage, output voltage, and given voltage; The trunk current is PID-regulated according to the target trunk current to obtain the trunk voltage; and the adjusted voltage of each branch is obtained according to the target trunk current and the current of each branch. The step of obtaining the regulating voltage of each branch based on the target main current and the current of each branch includes: Divide the target main current by the number of branches to obtain the target branch current; The step of dividing the target trunk current by the number of branches to obtain the target branch current includes: Get the number of branches that are currently functioning normally in real time; The target branch current is obtained by dividing the target main circuit current by the number of branches that can operate normally. The regulated current of each branch is obtained by PID regulation of the current of each branch based on the target branch current; The regulating voltage of each branch is obtained based on the regulating current of each branch; The control signals for each branch IGBT are obtained by adding the regulating voltage of each branch to the main voltage and then performing pulse width modulation. The IGBT control module is used to control the on / off state of each branch IGBT according to the control signal so that the current in each branch is the same.

5. An interleaved PFC circuit, characterized in that, include: The modulation module has at least two branches, with any two branches connected in parallel. Each branch includes an inductor, a freewheeling diode, and an IGBT; The modulation module is connected to the IGBTs of each branch and is used to control the on / off state of the IGBTs according to the method described in any one of claims 1-3.

6. The circuit according to claim 5, characterized in that, Also includes: A current sampling and conditioning module is provided on each branch, or the current sampling and conditioning module is provided on the main circuit and at least n-1 branches, where n is the total number of all branches.

7. The circuit according to claim 6, characterized in that: The current sampling and conditioning module includes a sampling resistor and an amplifier; One end of the sampling resistor is connected to the non-inverting input of the amplifier through a resistor, and the other end is connected to the inverting input of the amplifier through another resistor. The output of the amplifier is connected to the modulation module, and the output of the amplifier is also connected to the inverting input of the amplifier through a feedback resistor.

8. An air conditioner, characterized in that, Includes the circuit described in any one of claims 5-7.

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