JP2022534367A - Power factor correction circuit and air conditioner - Google Patents

Abstract

A power factor correction circuit and an air conditioner are provided, wherein the power factor correction circuit has an AC input end connected to an AC power supply, and a power factor correction module (10) used to rectify and output the AC power supply to DC. , a switching drive module connected to the driving input end of the power factor correction module (10) and used to output a switching signal to the power factor correction module (10); and a switching drive module connected to the switching drive module to drive the switching drive module. A control module (30) used to control the output on or off, a Hall current sensor (40) provided on the AC input side of the power factor correction module (10), a Hall current sensor (40) and a control module. (30) and used to determine whether to output a protection signal to the control module (30) based on the relationship between the sampling signal and the corresponding first safety threshold. and including. With this solution, it is possible to more directly detect whether an abnormality has occurred in the rectifier, and when determining the occurrence of an abnormality, it is possible to identify corresponding abnormal components in different operating states. [Selection drawing] Fig. 2

Description

This application is a Chinese patent application with application number 201910415198.2 and titled "Power Factor Correction Circuit and Air Conditioner", filed with the Chinese Patent Office on May 17, 2019; Claiming priority of a Chinese patent application entitled "Power Factor Correction Circuit and Air Conditioner" filed with the Chinese Patent Office on May 17, 201920710867.4, and the contents thereof is incorporated herein by reference in its entirety.

The present application relates to the field of air conditioning technology, and in particular to power factor correction circuits and air conditioners.

In the related art, power factor correction circuits (or PFC circuits) employ high-power MOS (metal-oxide-semiconductor) switching technology as the primary power device instead of IGBT (insulated gate bipolar transistor) devices, and turn on the IGBTs. The low on-resistance characteristic of MOS is utilized instead of the constant voltage drop characteristic to achieve reduction in power consumption at medium and low power levels, thereby realizing reduction in power consumption of an air conditioner.

Four switching transistors constitute a power factor correction module, and two half-bridge driving chips are used to drive, one of which has a protection function and is combined with a sampling resistor to detect overcurrent. , when a large current is detected, it triggers turning off the drive output to the four switches to provide overcurrent protection. However, this solution has the following defects.

As shown in FIG. 1, the conventional protection means can only detect when an abnormality occurs in upper and lower Q1 and Q3, or when an abnormality occurs in upper and lower Q2 and Q4. Since the switching drive module itself can incorporate an interlock protection circuit, shoot-through of the upper and lower bridge arms is less likely to occur. Therefore, the probability of failure corresponding to the protection means is low, and the practicality is relatively low.

The present application aims at solving at least one of the technical problems existing in the prior art or related art.

Therefore, one object of the present application is to provide a power factor correction circuit.

Another object of the present application is to provide an air conditioner.

To achieve the above objects, according to an embodiment of the first aspect of the present application, there is provided a power factor correction module for receiving a power supply signal, the power factor correction module configured to control the power supply signal to power a load. a switching drive module connected to a driving input terminal of the power factor correction module and used to output a switching signal to the power factor correction module; and a switching drive module connected to the power factor correction module. and a control module used to control the switching drive module to turn on or turn off the output of the switching signal, specifically a Hall current sensor. a current sensor installed at the input side of the power factor correction module to collect the input current and take the input current as a sampling signal; and connected to the Hall current sensor and the control module, wherein the sampling signal is a drive protection module outputting a protection signal to the control module if greater than a safety threshold of 1, wherein the protection signal is used to trigger the control module to turn off the output of the switching drive module. and a drive protection module.

In the technical means, a Hall current sensor is installed at the AC input end of the power factor correction module, the Hall current sensor collects the input current or the output current of the power factor correction module according to the installed position, and the current is converted into a sampling signal and output to the drive protection module to detect whether an overcurrent phenomenon has occurred. control to stop the output of As a result, the Hall current sensor does not make electrical contact with the circuit to be detected, so it does not consume the power of the power source to be detected, and therefore does not affect the highly efficient and low power consumption control of the inverter device. On the other hand, the Hall current sensor directly collects the input end current of the power factor correction module, so that when the power factor correction module performs different functional operations, the corresponding different current paths are all detected by the Hall current sensor for circuit failure. Therefore, it is possible to more directly detect whether or not an abnormality has occurred in the rectifier, and when the occurrence of an abnormality is determined, it is possible to identify corresponding abnormal components in different operating states. Compared with the prior art solution of using a driving chip with protection function to combine with the sampling resistor to detect overcurrent, it is less restrictive and has more directivity and practicality.

The first safety threshold is the input terminal voltage safety threshold.

A Hall current sensor is a sensor that uses the Hall effect to convert a primary large current into a secondary minute sampling signal, and is combined with an operational amplifier to amplify the minute sampling signal to a standard voltage. That is, the Hall current sensor outputs a sampling signal to the outside, and compares it with the safety threshold built in the drive protection module, and determines whether the short circuit overcurrent phenomenon occurs in the circuit according to the comparison result. Since the Hall current sensor can measure alternating current and can also measure direct current, it can be provided on the ac input side of the power factor correction module or on the dc output side of the power factor correction module. good.

The above technical solution further includes a sampling resistor provided at the negative output terminal of the power factor correction module and connected to the driving protection module, wherein the voltage drop across the sampling resistor is a second Outputting the protection signal to the control module when detecting that the safety threshold is exceeded.

In the technical means, a Hall current sensor is connected in series with the AC side of the power factor correction module to detect the current on the AC side, and then the sampling signal output from the sensor is sent to the input of the drive protection module. As a signal, coupled with a sampling resistor connected in series with the negative output end of the power factor correction module, the voltage detected by the sampling resistor is also input to the drive protection module, one of the two input voltages is current detection and When the preset voltage of the driving protection module is exceeded, the current detection and protection of the driving protection module will be triggered, and the power factor correction module will be turned off, so that both the input and output sides can realize the detection function of the overcurrent phenomenon. can.

The second safety threshold is the voltage safety threshold at the negative output of the power factor correction module.

In any one of the above technical means, a reactor provided between the power factor correction module and an AC power supply, a reactor provided between a live line end and a neutral line end of the AC power supply, and connected to the control module. and a zero-cross detection module used to collect a zero-cross detection signal between the live line end and the neutral line end, wherein the control module further comprises a zero-cross detection module output from the zero-cross detection module. The phase state of the AC power supply is specified based on the detection signal, and a switching control signal is output to the switching drive module based on the phase state, thereby controlling the reactor to be charged, The AC power supply is used to output the power supply signal.

In this technical means, by providing a reactor between the AC input end of the power factor correction module and the AC power supply, when the AC power supply performs AC output, the reactor converts the electrical energy supplied from the AC power supply into magnetic energy. It can be converted and stored as energy, and by releasing this energy, it is possible to boost the PFC circuit and improve the power factor.

Specifically, a zero-cross detection module is provided between the live line and the neutral line, and the real-time phase of the AC power supply is determined by the zero-cross detection module, so that the switching operation is performed according to different phase states. Different switching devices in the power factor correction module are driven to achieve rectification or power factor correction (PFC) functions respectively. Thereby, the DC power supply at the load end is realized based on the rectification function, or the AC side voltage and the AC side current are matched in phase by the PFC control.

In addition, there are various causes for the occurrence of the overcurrent phenomenon, such as circuit interference causing freeze and reset of the control module, short-circuit failure in the reactor, and the like.

In any of the above technical means, the Hall current sensor is provided between the AC power supply and the reactor, and the drive protection module further detects that the sampling signal is greater than a first safety threshold. is used to output the protection signal to the control module to turn off the output of the switching drive module when the output of the switching drive module is turned off.

The Hall current sensor may be placed in either the live line or the neutral line where the reactors are connected in series.

In any one of the above technical means, the power factor correction module comprises a first switching transistor, a second switching transistor, a third switching transistor, and a fourth switching transistor, and the first switching transistor and the fourth switching transistor. 2 switching transistors are provided in the upper part of the power factor correction module, the third switching transistor and the fourth switching transistor are provided in the lower part of the power factor correction module, the first switching transistor and the third switching transistor are in the power A second switching transistor and a fourth switching transistor are provided on the left side of the power factor correction module, and the first switching transistor, the second switching transistor, the third switching transistor are provided on the right side of the power factor correction module. and the fourth switching transistor are connected in anti-parallel with a freewheeling diode, the drain of the first switching transistor and the drain of the second switching transistor are connected in series, and the connection point is the output a positive output terminal of the rate improvement module, the source of the third switching transistor and the source of the fourth switching transistor are connected in series, the connection point is the negative output terminal, and is connected in series with the sampling resistor; The source of the first switching transistor and the drain of the third switching transistor are connected in series, the connection point is connected to the live line end, and the source of the second switching transistor and the third switching transistor are connected in series. 4 are connected in series with the drains of the switching transistors, and the connection point is connected to the end of the neutral line.

Specifically, each of the first switching transistor, the second switching transistor, the third switching transistor, and the fourth switching transistor is a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) , MOS transistors), such as superjunction MOSFETs or SiC-MOSFETs.

The operation method of the MOS transistor is to realize switching by controlling the on/off between the source and the drain by the gate, and the gate power supply should be greater than the source power supply when turning on.

In this technical solution, by providing a power factor correction module composed of four switching transistors, the circuit is combined with the control command output from the control module to perform rectification operation or power factor correction operation respectively. When controlling and making it a component part of a motor drive system, in order to achieve the purpose of increasing the allowable limit of the motor rotation speed, boosting is performed by alternately performing "power factor improvement operation" and "synchronous rectification operation", and during operation, by adding a current transformer and a Hall current sensor to the circuit, detecting the operating current, and controlling the power factor correction module to stop operation when an occurrence of current abnormality is detected, After removing the abnormality, it will restart, thereby ensuring the safety of the motor driving process.

In the technical means, a Hall current sensor is installed at the AC input end of the power factor correction module, so that whether the rectification operation or the power factor correction operation is performed, a current flows through the Hall current sensor, thereby When the Hall device detects current flow, the device will output the corresponding voltage, based on the current value that the four switching transistors of the power factor correction module can withstand, the drive protection module or the Hall current sensor built-in setting a voltage value that needs to be protected in the overcurrent detection unit; connecting a first switching transistor and a second switching transistor in series between the live line and the neutral line; connecting a third switching transistor and a fourth switching transistor; A transistor is connected in series between the live line and the neutral line, and when an abnormal overcurrent occurs in the first switching transistor-second switching transistor or third switching transistor-fourth switching transistor, the current outputs a corresponding voltage through the Hall current sensor and triggers the drive protection module, and turns off the switching signal of the switching drive module, thereby realizing overcurrent protection for the switching transistor. When the overcurrent signal is released, the drive protection module releases control over the overcurrent switching drive module and returns to normal operation. It achieves the purpose of improving the safety of the whole PFC circuit by realizing timely and effective detection of faults with relatively high probability either in the commutation operation process or in the power factor correction process. be able to.

For a power factor correction circuit equipped with a Hall current sensor and a sampling resistor, the voltage is sampled according to the Hall current sensor and/or the sampling resistor in different current paths, and a short circuit is detected based on the sampling voltage detection result. It can be determined whether the phenomenon exists or not. Therefore, it can meet the detection needs of the different coupling paths of the first switching transistor, the second switching transistor, the third switching transistor and the fourth switching transistor in the power factor correction module.

In any of the above technical means, the switching drive module comprises a first switching drive module used to drive the first switching transistor and the third switching transistor, and the second switching transistor and the a second switching drive module used to drive a fourth switching transistor, wherein the drive protection module detects that the sampling signal is greater than a first safety threshold and/or that the voltage drop is greater than a second safety threshold; When detecting greater than, triggering the control module to turn off the driving outputs of the first switching driving module and the second switching driving module.

In the technical solution, the switching driving module includes a first switching driving module and a second switching driving module, thereby realizing half-bridge driving of the H-bridge rectifier.

Also, as can be appreciated by those skilled in the art, when the control module controls the switching drive module to stop the drive output, it simultaneously controls the first switching drive module and the second switching drive module to stop the output. stop, ie the two switching drive modules have the same execution priority.

Specifically, the first switching transistor and the third switching transistor are driven by the first switching drive module, the second switching transistor and the fourth switching transistor are driven by the second switching drive module, and the Hall The sampling signal output from the current sensor and the voltage sampling signal of the sampling resistor are both connected to the drive protection module. when the driving protection module detects that the voltage output from the Hall current sensor and the voltage sampling signal at the sampling resistor exceed a preset value, the first switching driving module and the second switching driving module are forcibly turned off; It protects the four switching transistors.

The Hall current sensor is mainly used when the current passes through the first switching transistor and the second switching transistor in sequence, or when the current passes through the third switching transistor and the fourth switching transistor in sequence, when a short circuit fault occurs. The sampling resistor is mainly short-circuited when the current sequentially passes through the first switching transistor and the third switching transistor or the current sequentially passes through the second switching transistor and the fourth switching transistor. It is used for detection when an abnormality occurs.

As can be appreciated by those skilled in the art, the security signal triggered and generated based on the Hall current sensor and the guard signal triggered and generated based on the sampling resistor have the same priority. Any one of them will trigger the drive protection module, and the cause of overcurrent will be electromagnetic interference or surge interference in the circuit, causing the control module to freeze and reset, or short circuit fault in the reactor. and so on.

Any of the above technical means further includes a bus capacitor connected to the DC output terminal of the power factor correction module and provided in parallel with the load drive module.

In any one of the above technical means, the control module further comprises a switch for turning on the first switching transistor and the fourth switching transistor when the input voltage of the AC power supply is in a positive half cycle. It is used to control the switching drive module to output a switching signal and bypass the corresponding freewheeling diode. The control module further outputs a switching signal for turning on the second switching transistor and the third switching transistor when the input voltage of the AC power supply is in a negative half cycle, and corresponding It is used to control the switching drive module to bypass the freewheeling diode to achieve synchronous rectification.

There is a freewheeling diode inside the first switching transistor, the freewheeling diode is part of the PN junction that exists between the source and the drain of the first switching transistor, and the saturation voltage of the first switching transistor (on drain-to-source voltage in the state) is lower than the forward voltage drop of the freewheeling diode. As a result, the voltage drop of the current flowing through the source and drain of the first switching transistor is smaller than that of the current flowing through the parasitic diode, thereby reducing the conduction loss. As can be easily understood, conduction losses are greater when current flows through the first switching transistor in the ON state than in the freewheeling diode of the first switching transistor in the OFF state. become smaller. It is also applicable to other second switching transistors, third switching transistors, and fourth switching transistors.

In this technical means, by utilizing the principle of low on-voltage drop of MOS transistors, synchronous rectification with low power consumption can be realized by turning on corresponding MOS transistors according to the phase state of AC power. .

Specifically, the control module outputs a corresponding control signal according to the phase of the current AC power detected by the zero-cross detection module to drive the corresponding switching transistor to operate.

In the related art, when performing synchronous rectification, when in the positive half cycle of the AC power supply, the current passes through the Hall current sensor and the reactor, and then through the freewheeling diode of the first switching transistor and the fourth switching transistor. rectified to power the system, at which time the voltage drop of the freewheeling diode is large, causing wasted energy.

In this technical means, in this case, the control module determines that the current passes through the Hall current sensor and the reactor at the beginning of the positive half cycle of the AC power supply based on the zero-crossing detection module, and outputs a switching signal to the first and the fourth switching transistor are turned on, the current flowing through the first switching transistor, the sampling resistor, and the freewheel diode in the fourth switching transistor is caused to flow through the MOS transistor, and the low on-state characteristics of the MOS transistor are improved. utilized to bypass the freewheeling diode, thereby reducing conduction losses. Similarly, when the AC power supply is in the negative half cycle, the control module controls the second switching transistor and the third switching transistor to turn on, causing the four MOS transistors to realize the synchronous rectification function, and the synchronous rectification In the process, the current passing through the Hall current sensor and the sampling resistor is detected to detect whether the overcurrent phenomenon occurs.

In any one of the above technical means, the control module further controls the third switching transistor and the ON/OFF of a fourth switching transistor is controlled, and when the third switching transistor and the fourth switching transistor are turned on, the reactor is charged and the third switching transistor and the fourth switching transistor are switched on. When turning off and turning on the first switching transistor, the reactor is used to power a load, the control module further determines that when the input voltage of the AC power supply is in the negative half cycle, the ON/OFF of the third switching transistor and the fourth switching transistor is controlled based on the zero cross detection signal and the switching signal, and when the third switching transistor and the fourth switching transistor are turned on, the reactor and drives the second switching transistor to turn on when the third switching transistor and the fourth switching transistor are turned off, and the reactor is used to supply power to a load. , to achieve power factor improvement.

In this technical solution, when the circuit is used to perform PFC operation, when the input is in the positive half cycle of the AC power supply, the control module switches the third switching transistor and the fourth switching transistor according to the zero-cross detection signal according to the zero-crossing detection signal. driving the transistor to turn on and charging the reactor; in the charging process, detecting the current on the Hall current sensor to determine whether the short circuit phenomenon occurs; the third switching transistor and the fourth switching transistor; When turning off, the control module drives the first switching transistor to turn on, and the electrical energy stored in the reactor is released to the subsequent circuit by the first switching transistor to supply power to the bus capacitor and the load (such as the motor). do. When the input is in the negative half cycle of the AC power supply, the control module drives the third switching transistor and the fourth switching transistor on according to the zero-crossing detection signal, charges the reactor, and charges the third switching transistor and When the fourth switching transistor is turned off, the control module drives the second switching transistor to turn on, the electrical energy stored in the reactor is released to the subsequent circuit by the second switching transistor, and the bus capacitor and the load ( For example, a motor) is supplied with power, and the energy accumulated in the reactor is released to the bus capacitor, thereby boosting the DC voltage of the bus capacitor. Thereby, the distortion of the current waveform can be reduced by the short-circuit current, the current waveform can be approximated to a sine wave, and the power factor of the PFC circuit can be improved. Furthermore, by calculating the pulse width of the third switching transistor or the first switching transistor based on the bus voltage of the load, the duration of the short circuit current in the PFC circuit can be reasonably adjusted, and the pulse change times can reasonably control the on/off times of each switch to reduce the conduction loss of the switching unit, reduce the switching loss, and improve the efficiency.

Any of the above technical means further includes a bus capacitor, one end of the bus capacitor is connected to the positive output terminal, the other end of the bus capacitor is grounded, the switching drive module outputs the switching signal, The AC power supply charges the bus capacitor or discharges the bus capacitor, and the switching drive module does not output the switching signal and discharges the bus capacitor.

In any one of the above technical means, a load driving module connected to a DC output end of the power factor correction module and used to receive the DC output of the power factor correction module to supply power to a load; a DC bus voltage detection module connected to the DC output end of the rate improvement module and provided in parallel with the load driving module and used to detect the DC bus voltage.

According to this technical solution, in the application scene where the load is a motor, the load driving module is used to inversely transform constant voltage direct current into three-phase alternating current and output it, so as to realize power supply to the motor. In combination with the installation of the bus voltage detection module, the detection of the DC output of the power factor correction module to the bus voltage and the input voltage to detect the switching state of each transistor element in the power factor correction module and the ON time of each transistor element control the pulse width of

In any of the above technical means, the control module is further connected to a load driving module and used to output an inverse conversion control signal to the load driving module.

According to an embodiment of the second aspect of the present application, there is provided an air conditioner including the power factor correction circuit according to the technical means of the first aspect of the present application.

Specifically, the power factor correction circuit is applied to the compressor motor drive system, and by detecting whether an overcurrent phenomenon occurs in the circuit, the motor rotation speed is too high when the overcurrent occurs, and the compressor to prevent demagnetization from occurring.

Additional aspects and advantages of the present application will be set forth in the description section below, and in part will become apparent from the ensuing description, or may be learned by practice of the present application.

The above and/or additional aspects and advantages of the present application will become clearer and more comprehensible through the description of the embodiments with the aid of the following drawings.

1 shows a schematic diagram of a power factor correction circuit in the related art; FIG. 1 shows a schematic diagram of a power factor correction circuit according to one embodiment of the present application; FIG.

In order to understand the above objects, features and advantages of the present application more clearly, the following describes the present application in more detail with reference to the drawings and specific embodiments. It should be noted that the embodiments of the present application and the configurations in the embodiments can be combined with each other unless contradictory.

Although numerous specific details are set forth in the following description in order to provide a thorough understanding of the present application, the present application may also be embodied in other forms than those described herein and, therefore, the protection The scope is not limited to the specific examples disclosed below.

(Example 1)
As shown in FIG. 2, the power factor correction circuit according to one embodiment of the present application is a power factor correction module 10 that is applied to an air conditioner and receives a power supply signal. a power factor correction module 10 comprising a switching transistor configured to supply power; and a switching drive connected to a drive input of said power factor correction module 10 and used to output a switching signal to said power factor correction module 10. a control module 30 connected to the switching drive module and used to control the switching drive module to turn on or turn off the output of the switching signal; and the power factor. A Hall current sensor 40 provided on the input side of the improvement module 10 to collect input current and use the input current as a sampling signal; a drive protection module 50 for outputting a protection signal to the control module 30 if greater than a first safety threshold, the protection signal triggering the control module 30 to turn off the output of the switching drive module; and a drive protection module 50 used for

In this embodiment, a Hall current sensor 40 is installed at the AC input terminal of the power factor correction module 10, and the Hall current sensor 40 collects the input current or output current of the power factor correction module 10 according to the installation position. and converting the current into a sampling signal and outputting it to the drive protection module 50 for detecting whether or not an overcurrent phenomenon has occurred by the drive protection module 50, and improving the power factor when the occurrence of the overcurrent phenomenon is detected. The output of the switching signal to the module 10 is controlled to stop, and the Hall current sensor 40 is not in electrical contact with the circuit to be detected, so it does not consume the power of the power supply to be detected, so that the inverter device has high efficiency and low power consumption. Because the Hall current sensor 40 directly collects the input end current of the power factor correction module 10 while not affecting the control of power consumption, and the input end is connected to the live line and neutral line end N of the AC power supply. , it is possible to more directly detect whether an abnormality has occurred in the rectifier, and when it is determined that an abnormality has occurred, it is possible to determine the corresponding abnormal components in different operating conditions. Compared with the solution of using a driving chip with a protection function to combine with the sampling resistor Rs to detect overcurrent, it is less restrictive and has more directivity and practicality.

The Hall current sensor 40 is a sensor that uses the Hall effect to convert a primary large current into a secondary minute sampling signal, and is combined with an operational amplifier to amplify the minute sampling signal to a standard voltage, that is, the Hall current sensor 40 is The Hall current sensor 40 outputs a sampling signal to the outside and compares it with the safety threshold built in the drive protection module 50. Based on the comparison result, it determines whether the short circuit overcurrent phenomenon occurs in the circuit. Since AC can be measured and DC can also be measured, it may be provided on the AC input side of the power factor correction module 10 or may be provided on the DC output side of the power factor correction module 10 .

(Example 2)
After installing the Hall current sensor 40, as shown in FIG. Further comprising, the drive protection module 50 outputs the protection signal to the control module 30 when it detects that the voltage drop across the sampling resistor Rs exceeds a second safety threshold.

In this embodiment, a Hall current sensor 40 is connected in series to the AC side of the power factor correction module 10 to detect the current on the AC side, and then the sampling signal output from the sensor is sent to the drive protection module 50. , the voltage detected by the sampling resistor Rs is also input to the drive protection module 50, and the two input voltages If either exceeds the preset voltage of the current detection and drive protection module 50 , both will trigger protection of the current detection and drive protection module 50 and turn off the power factor correction module 10 .

In any of the above embodiments, a reactor L1 provided between the power factor correction module 10 and an AC power supply, a reactor L1 provided between a live line end L and a neutral line end N of the AC power supply, and the control a zero-cross detection module 60 connected to the module 30 and used to collect a zero-cross detection signal between the live line end L and the neutral line end N; The phase state of the AC power supply is specified based on the zero-cross detection signal output from the zero-cross detection module 60, and the switching control signal is output to the switching drive module based on the phase state to charge the reactor L1. used to control

In this embodiment, by providing a reactor L1 between the AC input end of the power factor correction module 10 and the AC power supply, when the AC power supply performs AC output, the reactor L1 converts the electrical energy supplied from the AC power supply into a magnetic field. It can be converted into energy and stored as energy, and by releasing this energy, it is possible to boost the PFC circuit and improve the power factor.

Specifically, a zero-cross detection module 60 is provided between the live line and the neutral line, and the real-time phase of the AC power source is determined by the zero-cross detection module 60, so that switching operations are performed based on different phase conditions. to drive the different switching devices in the power factor correction module 10 to respectively achieve a rectification function or a power factor correction (PFC) function, thereby realizing DC power supply at the load end based on the rectification function or PFC The AC side voltage and the AC side current are matched in phase by control.

In addition, there are various causes for the occurrence of the overcurrent phenomenon, for example, circuit interference causes freezing and resetting of the control module 30, or a short-circuit abnormality occurs in the reactor L1.

(Example 3)
As shown in FIG. 2, in any of the above embodiments, the power factor correction module 10 comprises a first switching transistor Q1, a second switching transistor Q2, a third switching transistor Q3 and a fourth switching transistor Q4. A first switching transistor Q1 and a second switching transistor Q2 are arranged in the upper part of the power factor correction module 10, and a third switching transistor Q3 and a fourth switching transistor Q4 are arranged in the lower part of the power factor correction module 10. a first switching transistor Q1 and a third switching transistor Q3 are provided on the left side of the power factor correction module 10; a second switching transistor Q2 and a fourth switching transistor Q4 are provided on the right side of the power factor correction module 10; freewheeling diodes are connected in anti-parallel to the first switching transistor Q1, the second switching transistor Q2, the third switching transistor Q3 and the fourth switching transistor Q4, and the first The drain of the switching transistor Q1 and the drain of the second switching transistor Q2 are connected in series, and the connection point is determined as the positive output terminal of the power factor correction module. The source of the switching transistor Q4 is connected in series, the connection point is connected in series with the sampling resistor Rs and then grounded, and the source of the first switching transistor Q1 and the drain of the third switching transistor Q3 are connected in series. and a connection point is connected to the live line terminal L, the source of the second switching transistor Q2 and the drain of the fourth switching transistor Q4 are connected in series, and the connection point is connected to the neutral line terminal N. be.

Specifically, the first switching transistor Q1, the second switching transistor Q2, the third switching transistor Q3, and the fourth switching transistor Q4 are all MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistor). semiconductor field effect transistors, ie MOS transistors), for example superjunction MOSFETs, or SiC-MOSFETs.

The operation method of the MOS transistor is to realize switching by controlling the on/off between the source and the drain by the gate, and the gate power must be greater than the source power when turning on.

In this embodiment, the power factor correction module 10 is provided with four switching transistors to combine with the control command output from the control module 30 to perform the rectification operation or the power factor correction operation respectively. is used as a component of the motor drive system, in order to achieve the purpose of raising the allowable limit of the motor rotation speed, the voltage is boosted by alternately performing "power factor correction operation" and "synchronous rectification operation". and during operation, by adding a current transformer and a Hall current sensor to the circuit, the operating current is detected, and the power factor correction module 10 is controlled to stop operating when an abnormal current is detected. and restart after eliminating the abnormality, thereby ensuring the safety of the motor driving process.

In this embodiment, the Hall current sensor 40 is installed at the AC input end of the power factor correction module 10, so that no current flows through the Hall current sensor 40 whether the rectification operation or the power factor correction operation is performed. When it detects that the Hall device is flowing, thereby causing current to flow through the Hall device, the device will output a corresponding voltage, and the drive protection module 50 or Hall A voltage value requiring protection is set in the overcurrent detection unit built in the current sensor 40, the first switching transistor Q1 and the second switching transistor Q2 are connected in series between the live line and the neutral line, 3 switching transistors Q3 and a fourth switching transistor Q4 are connected in series between the live line and the neutral line, and the first switching transistor Q1-the second switching transistor Q2 or the third switching transistor Q3-the fourth switching transistor Q3 are connected in series. When an abnormal overcurrent occurs in the switching transistor Q4 of the switching transistor Q4, the current will output a corresponding voltage by the hall current sensor 40 and trigger the drive protection module 50, and turn off the switching signal of the switching drive module, thereby switching Implementing overcurrent protection for the transistor, when the overcurrent signal is released, the drive protection module 50 will release control over the overcurrent switching drive module and return to normal operation, so that in the course of rectification operation or the power factor Realizing the timely and effective detection of faults with relatively high probability during the improvement process can achieve the purpose of improving the safety of the whole PFC circuit.

For the power factor correction circuit installed with the Hall current sensor 40 and the sampling resistor Rs, the voltage is sampled according to the Hall current sensor 40 and/or the sampling resistor Rs in different current paths, and the detection result of the sampling voltage is Therefore, the first switching transistor Q1, the second switching transistor Q2, the third switching transistor Q3 and the fourth switching transistor Q3 in the power factor correction module 10 can be determined based on It can meet the detection needs of different coupling paths of the switching transistor Q4.

In any of the above embodiments, the switching driver module comprises a first switching driver module 202 used to drive the first switching transistor Q1 and the third switching transistor Q3, and the second switching transistor. Q2 and a second switching drive module 204 used to drive the fourth switching transistor Q4, wherein the drive protection module 50 ensures that the sampling signal is greater than a first safety threshold and/or the voltage Triggering the control module 30 to turn off the drive outputs of the first switching drive module 202 and the second switching drive module 204 when detecting that the drop is greater than a second safety threshold.

In this embodiment, the switching driving module includes a first switching driving module 202 and a second switching driving module 204, thereby realizing half-bridge driving of the H-bridge rectifier.

Also, as those skilled in the art will appreciate, when the control module 30 controls the switching drive modules to stop the drive output, it simultaneously controls the first switching drive module 202 and the second switching drive module 204 . ie the two switching drive modules have the same execution priority.

Any of the above embodiments further includes a bus capacitor E connected to the DC output terminal of the power factor correction module 10 and provided in parallel with the load driving module 70 .

(Example 4)
As shown in FIG. 2, in any one of the embodiments described above, the Hall current sensor 40 is provided between the AC power supply and the reactor L1, and the drive protection module 50 further detects that the sampling signal is the first It is used to output the protection signal to the control module 30 to turn off the output of the switching drive module when it is detected to be greater than a safety threshold of 1;

The Hall current sensor 40 may be arranged at any position of the live line or the neutral line to which the reactor L1 is connected in series.

In this embodiment, the Hall current sensor 40 is installed at the AC input end of the power factor correction module 10, so that no current flows through the Hall current sensor 40 whether the rectification operation or the power factor correction operation is performed. When detecting a current flowing through the Hall device, the device outputs a corresponding voltage, and according to the current value that the four switching transistors of the power factor correction module 10 can withstand, the drive protection module 50 or the Hall device A voltage value requiring protection is set in the overcurrent detection unit built in the current sensor 40, the first switching transistor Q1 and the second switching transistor Q2 are connected in series between the live line and the neutral line, 3 switching transistors Q3 and a fourth switching transistor Q4 are connected in series between the live line and the neutral line, and the first switching transistor Q1-the second switching transistor Q2 or the third switching transistor Q3-the fourth switching transistor Q3 are connected in series. When an abnormal overcurrent occurs in the switching transistor Q4 of the switching transistor Q4, the current will output a corresponding voltage by the hall current sensor 40 and trigger the drive protection module 50, and turn off the switching signal of the switching drive module, thereby switching Implementing overcurrent protection for the transistor, when the overcurrent signal is released, the drive protection module 50 will release control over the overcurrent switching drive module and return to normal operation, so that during the commutation process or power By realizing timely and effective detection of faults with relatively high probability in the rate improvement process, the purpose of improving the safety of the whole PFC circuit can be achieved.

For the power factor correction circuit installed with the Hall current sensor 40 and the sampling resistor Rs, the voltage is sampled according to the Hall current sensor 40 and/or the sampling resistor Rs in different current paths, and the detection result of the sampling voltage is Therefore, the first switching transistor Q1, the second switching transistor Q2, the third switching transistor Q3 and the fourth switching transistor Q3 in the power factor correction module 10 can be determined based on It can meet the detection needs of different coupling paths of the switching transistor Q4.

driving the first switching transistor Q1 and the third switching transistor Q3 by the first switching driving module 202, driving the second switching transistor Q2 and the fourth switching transistor Q4 by the second switching driving module 204; The sampling signal output from the hall current sensor 40 and the voltage sampling signal of the sampling resistor Rs are both connected to the driving protection module 50, and the driving protection module 50 receives the voltage output from the hall current sensor 40 and the voltage sampling at the sampling resistor Rs. When it detects that the signal exceeds the preset value, it forces the first switching driving module 202 and the second switching driving module 204 to turn off, thereby protecting the four switching transistors.

The Hall current sensor 40 is mainly short-circuited when the current sequentially passes through the first switching transistor Q1 and the second switching transistor Q2 or the current sequentially passes through the third switching transistor Q3 and the fourth switching transistor Q4. The sampling resistor Rs is mainly used for detection when an abnormality occurs. is used to detect a short-circuit abnormality when passing through the switching transistor Q4 in sequence.

As can be understood by those skilled in the art, the protection signal triggered and generated based on the Hall current sensor 40 and the protection signal triggered and generated based on the sampling resistor Rs have the same priority. or one of the abnormalities will trigger the drive protection module 50, and the cause of the overcurrent is that the circuit will be subject to electromagnetic interference or surge interference, causing the control module 30 to freeze and reset, or the reactor L1 to short circuit. occurs.

(Example 5)
In any of the above embodiments, the control module 30 is further configured to turn on the first switching transistor Q1 and the fourth switching transistor Q4 when the AC power input voltage is in a positive half cycle. and used to control the switching drive module to bypass the corresponding freewheel diode. the control module 30 further outputs a switching signal for turning on the second switching transistor Q2 and the third switching transistor Q3 when the input voltage of the AC power supply is in a negative half cycle; and used to control the switching drive module to bypass the corresponding freewheel diode to achieve synchronous rectification.

There is a freewheeling diode inside the first switching transistor Q1, the freewheeling diode being the part of the P junction that exists between the source and the drain of the first switching transistor Q1, and the saturation of the first switching transistor Q1. The voltage (drain-source voltage in the ON state) is lower than the forward voltage drop of the freewheeling diode. As a result, the voltage drop of the current flowing through the source and drain of the first switching transistor Q1 is smaller than that of the current flowing through the parasitic diode, thereby reducing the conduction loss. As can be easily understood, the current flowing through the first switching transistor Q1 in the ON state makes the conduction loss smaller than the current flowing in the freewheeling diode of the first switching transistor Q1 in the OFF state. Also, it can be applied to other second switching transistor Q2, third switching transistor Q3 and fourth switching transistor Q4.

In this embodiment, by utilizing the principle of low on-voltage drop of MOS transistors, synchronous rectification with low power consumption can be realized by turning on corresponding MOS transistors according to the phase state of AC power.

Specifically, the control module 30 outputs a corresponding control signal based on the phase of the current AC power detected by the zero-cross detection module 60 to drive the corresponding switching transistor to operate.

In the related art, when performing synchronous rectification, when it is in the positive half cycle of the AC power supply, the current passes through the Hall current sensor 40 and the reactor L1, followed by the first switching transistor Q1 and the fourth switching transistor Q4. It is rectified through the freewheeling diode to power the system, at which time the voltage drop of the freewheeling diode is large, causing a waste of energy.

In this embodiment, in this case, the control module 30 determines based on the zero-crossing detection module 60 that current passes through the Hall current sensor 40 and the reactor L1 at the beginning of the positive half cycle of the AC power supply, and outputs a switching signal. to turn on the first switching transistor Q1 and the fourth switching transistor Q4, and the current flowing through the freewheeling diode in the first switching transistor Q1, the sampling resistor Rs and the fourth switching transistor Q4 is caused to flow through the MOS transistor. , take advantage of the low on-characteristics of MOS transistors to bypass the freewheeling diode, thereby reducing conduction losses. Similarly, during the negative half-cycle of the AC power supply, the control module 30 controls the second switching transistor Q2 and the third switching transistor Q3 to turn on, causing the four MOS transistors to achieve the synchronous rectification function. , during the synchronous rectification process, the current passing through the Hall current sensor 40 and the sampling resistor Rs is detected to detect whether an overcurrent phenomenon has occurred.

(Example 6)
In any of the above embodiments, the control module 30 further controls the switching of the third switching transistor Q3 and the switching transistor Q3 based on the zero-cross detection signal and the switching signal when the input voltage of the AC power supply is in a positive half cycle. ON/OFF of the fourth switching transistor Q4 is controlled, the third switching transistor Q3 and the fourth switching transistor Q4 are turned on, the reactor L1 is charged, and the third switching transistor Q3 and the fourth switching transistor Q4 are charged. 4 switching transistor Q4 is turned off, the first switching transistor Q1 is turned on, the reactor L1 is used to power a load, the control module 30 further determines that the input voltage of the AC power supply is negative. If it is in the half cycle, it controls on/off of the third switching transistor Q3 and the fourth switching transistor Q4 based on the zero cross detection signal and the switching signal, and controls the third switching transistor Q3 and the fourth switching transistor Q4. The switching transistor Q4 is turned on to charge the reactor L1, the third switching transistor Q3 and the fourth switching transistor Q4 are turned off, and the second switching transistor Q2 is turned on. , the reactor L1 is used to power the load to achieve power factor correction.

In this embodiment, when the circuit is used to perform PFC operation, when the input is in the positive half cycle of the AC power supply, the control module 30 will switch the third switching transistor Q3 and the fourth switching transistor Q3 based on the zero-crossing detect signal. when driving the switching transistor Q4 on to charge the reactor L1 and turn off the third switching transistor Q3 and the fourth switching transistor Q4, the control module 30 drives the first switching transistor Q1 on; The electrical energy stored in the reactor L1 is released by the first switching transistor Q1 to the subsequent circuit to power the bus capacitor E and the load (e.g. motor), and when the input is in the negative half cycle of the AC power supply, the control module 30 turns on the third switching transistor 3 and the fourth switching transistor Q4 based on the zero-cross detection signal, charges the reactor L1, and turns off the third switching transistor Q3 and the fourth switching transistor Q4. When the control module 30 turns on the second switching transistor Q2, the electrical energy stored in the reactor L1 is released to the subsequent circuit by the second switching transistor Q2, and the bus capacitor E and the load (for example, the motor) By feeding the power and releasing the energy accumulated in the reactor L1 to the bus capacitor E, the DC voltage of the bus capacitor E can be boosted, thereby reducing the distortion of the current waveform due to the short-circuit current. By approximating a sine wave and further improving the power factor of the PFC circuit, and calculating the pulse width of the third switching transistor Q3 or the first switching transistor Q1 based on the bus voltage of the load, The duration of the short circuit current in the PFC circuit can be reasonably adjusted, and the on/off times of each switch can be reasonably controlled according to the pulse change times, reducing the conduction loss of the switching unit and reducing the switching loss. can be reduced and efficiency can be improved.

In any of the above embodiments, further comprising a bus capacitor E, one end of the bus capacitor E is connected to the positive output terminal, the other end of the bus capacitor E is grounded, and the switching driving module receives the switching signal. and the AC power supply charges or discharges the bus capacitor E, and the switching driving module does not output the switching signal and causes the bus capacitor E to discharge.

In any of the above embodiments, a load driving module 70 connected to the DC output end of the power factor correction module 10 and used to receive the DC output of the power factor correction module 10 to power a load; a DC bus voltage detection module (not shown) connected to the DC output terminal of the power factor correction module 10 and provided in parallel with the load driving module 70 and used to detect the DC bus voltage; include.

In this embodiment, in the application scene where the load is a motor, the load driving module 70 is used to reversely convert constant voltage DC to three-phase AC for output, so as to realize power supply to the motor. Combined with the installation of the bus voltage detection module, the detection of the DC output of the power factor correction module 10 to the bus voltage and the detection of the input voltage can determine the switching state of each transistor element in the power factor correction module 10 and the on state of each transistor element. Controls the pulse width of the hour.

In any of the above embodiments, the control module 30 is further connected to a load driving module 70 and used to output an inverse control signal to the load driving module 70 .

An air conditioner according to an embodiment of the present application includes the power factor correction circuit described in any one of the above embodiments.

Specifically, the power factor correction circuit is applied to the compressor motor drive system, and by detecting whether an overcurrent phenomenon occurs in the circuit, the motor rotation speed is too high when the overcurrent occurs, and the compressor to prevent demagnetization from occurring.

Compared with the prior art, the embodiments disclosed in the technical means of the present application have at least the following beneficial effects (1) to (3).

(1) The Hall current sensor directly collects the input end current of the power factor correction module, so that when the power factor correction module performs different functional operations, the corresponding different current paths are detected by the Hall current sensor. Therefore, it is possible to more directly detect whether an abnormality has occurred in the rectifier, and when it is determined that an abnormality has occurred, it is possible to determine the corresponding abnormal components in different operating conditions. , Compared with the prior art solution of using a driving chip with protection function to combine with sampling resistor to detect overcurrent, it is less restrictive and has more directivity and practicality.

(2) connecting a Hall current sensor in series with the AC side of the power factor correction module to detect the current on the AC side, and then taking the sampling signal output from the sensor as the input signal of the drive protection module; Coupled with a sampling resistor connected in series with the negative output end of the power factor correction module, the voltage detected by the sampling resistor is also input to the drive protection module, and one of the two input voltages is the current detection and drive protection module. exceeds the preset voltage, the protection of the current detection and drive protection module is triggered, and the power factor correction module is turned off, so that both the input and output sides can realize the detection function against overcurrent phenomenon.

(3) For a power factor correction circuit equipped with a Hall current sensor and a sampling resistor, sampling the voltage in different current paths according to the Hall current sensor and/or the sampling resistor, and according to the sampling voltage detection result Therefore, the different combinations of the first switching transistor, the second switching transistor, the third switching transistor and the fourth switching transistor in the power factor correction module. It can meet the detection demand of the flow path.

The above describes the technical means of the present application in detail in combination with the drawings. In order to detect the current on the AC side, a Hall current sensor is connected in series on the AC side of the power factor correction module, and then from the sensor The output sampling signal is used as the input signal of the drive protection module, and is combined with a sampling resistor connected in series with the negative output terminal of the power factor correction module, and the voltage detected by the sampling resistor is also input to the drive protection module, If either of the two input voltages exceeds the preset voltage of the current detection and drive protection module, it will trigger the protection of the current detection and drive protection module and turn off the power factor correction module.

As will be appreciated by those skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. The present application also describes a computer implemented on one or more computer-usable storage media (including, but not limited to, magnetic disk memory, CD-ROM, optical memory, etc.) containing computer-usable program code. A form of program product can be used.

This application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It should be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor or processor of other programmable data processing apparatus to produce a single apparatus, thereby rendering the processor of the computer or other programmable data processing apparatus The instructions executed by produce an apparatus for performing the functions specified in the flow or flows in the flowcharts and/or the block or blocks in the block diagrams.

These computer program instructions may be stored in a computer readable memory that direct a computer or other programmable data processing apparatus to operate in a particular manner, whereby the instructions stored in the computer readable memory are The instructions produce an article of manufacture that includes instruction devices that implement the functions specified in a flow or flows in flowcharts and/or in a block or blocks in block diagrams.

These computer program instructions may be loaded into a computer or other programmable data processing apparatus to cause the computer or other programmable apparatus to perform a series of operational steps to produce a computer-implementable process. Often, instructions executed on a computer, or other programmable device, are executed thereby to implement the functions specified in a flow or flows in the flowchart illustrations and/or in a block or blocks in the block diagrams. provide steps for

In the claims, it should be noted that any reference signs placed between parentheses shall not be construed as limiting the claim. The term "comprising" does not exclude the presence of elements or steps not listed in a claim. The term "one" or "one" preceding an item does not exclude the presence of a plurality of such items. The present application can be implemented by means of hardware including several different parts and a suitably programmed computer. In modular claims enumerating several devices, several of these devices can be embodied by one and the same item of hardware. The use of the terms first, second, third, etc. does not indicate any order. These terms can be interpreted as names.

Although preferred embodiments of the present application have been described, those skilled in the art can make other changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the appended claims should be interpreted as covering the preferred embodiment and all changes and modifications that fall within the scope of this application.

Clearly, one of ordinary skill in the art can make various modifications and variations to this application without departing from the scope of the claims and equivalents thereof, and it is intended that this application also includes these modifications and variations. do.

Claims (11)

a power factor correction module for receiving a power supply signal, the power factor correction module including a switching transistor configured to control the power supply signal to power a load;
a switching drive module connected to a drive input end of the power factor correction module and used to output a switching signal to the power factor correction module;
a control module connected to the switching drive module and used to control the switching drive module to turn on or turn off the output of the switching signal;
a current sensor installed at the input side of the power factor correction module for collecting an input current and taking the input current as a sampling signal;
a drive protection module connected to the current sensor and the control module and outputting a protection signal to the control module if the sampling signal is greater than a first safety threshold, the protection signal being the output of the switching drive module; a drive protection module used to trigger the control module to turn off the power factor correction circuit. further comprising a sampling resistor provided at the negative output end of the power factor correction module and connected to the drive protection module, wherein the drive protection module detects that the voltage drop across the sampling resistor exceeds a second safety threshold; 2. The power factor correction circuit of claim 1, outputting said protection signal to said control module when said power factor correction circuit. a reactor provided between the power factor correction module and an AC power supply;
a zero crossing provided between a live line end and a neutral line end of the AC power supply and connected to the control module and used to collect a zero crossing detection signal between the live line end and the neutral line end; further comprising a detection module;
The control module further identifies a phase state of the AC power supply based on the zero-cross detection signal output from the zero-cross detection module, and outputs a switching control signal to the switching drive module based on the phase state. is used to control the reactor to charge,
3. The power factor correction circuit of claim 2, wherein said AC power supply is used to output said power supply signal. The current sensor is provided between the AC power supply and the reactor,
The drive protection module is further used to output the protection signal to the control module to turn off the output of the switching drive module when detecting that the sampling signal is greater than a first safety threshold. 4. The power factor correction circuit of claim 3, wherein: The power factor correction module is composed of a first switching transistor, a second switching transistor, a third switching transistor and a fourth switching transistor, and the first switching transistor, the second switching transistor and the 3 and the fourth switching transistor are connected in anti-parallel with a freewheel diode, the drain of the first switching transistor and the drain of the second switching transistor are connected in series, and the connection point is the The positive output terminal of the power factor correction module is connected in series with the source of the third switching transistor and the source of the fourth switching transistor, and the connection point is the negative output terminal and is connected in series with the sampling resistor. The source of the first switching transistor and the drain of the third switching transistor are connected in series, the connection point is connected to the live line end, and the source of the second switching transistor and the 5. A power factor correction circuit according to claim 4, connected in series with the drain of said fourth switching transistor and having a connection point connected to said neutral line end. The switching drive module is a first switching drive module used to drive the first switching transistor and the third switching transistor, and for driving the second switching transistor and the fourth switching transistor. a second switching drive module for
When the drive protection module detects that the sampling signal is greater than a first safety threshold and/or the voltage drop is greater than a second safety threshold, the drive protection module triggers the control module to perform the first switching drive. 6. The power factor correction circuit of claim 5, wherein the module and the drive output of the second switching drive module are turned off. The control module further outputs a switching signal for turning on the first switching transistor and the fourth switching transistor when the input voltage of the AC power supply is in a positive half cycle, and corresponding used to control the switching drive module to bypass the freewheeling diode;
The control module further outputs a switching signal for turning on the second switching transistor and the third switching transistor when the input voltage of the AC power supply is in a negative half cycle, and corresponding 6. The power factor correction circuit of claim 5, used to control the switching drive module to bypass a freewheeling diode to achieve synchronous rectification. The control module further controls on/off of the third switching transistor and the fourth switching transistor based on the zero-crossing detection signal and the switching signal when the input voltage of the AC power supply is in a positive half cycle. and when the third switching transistor and the fourth switching transistor are turned on, the reactor is charged, and when the third switching transistor and the fourth switching transistor are turned off, the first turning on the switching transistor, the reactor is used to feed the load;
The control module further controls on/off of the third switching transistor and the fourth switching transistor based on the zero-cross detection signal and the switching signal when the input voltage of the AC power supply is in a negative half cycle. and when the third switching transistor and the fourth switching transistor are turned on, the reactor is charged, and when the third switching transistor and the fourth switching transistor are turned off, the second 6. The power factor correction circuit of claim 5, wherein the reactor is used to power a load by driving a switching transistor on to provide power factor correction. further comprising a bus capacitor, one end of the bus capacitor is connected to the positive output terminal, the other end of the bus capacitor is grounded, and the switching drive module, when outputting the switching signal, causes the bus capacitor to be driven by the AC power supply; 6. The power factor correction circuit of claim 5, charging or discharging the bus capacitor, and discharging the bus capacitor when the switching drive module does not output the switching signal. further comprising a load driving module connected to the DC output end of the power factor correction module and used to receive the DC output of the power factor correction module to power a load;
The power factor correction circuit according to any one of claims 1 to 8, wherein said control module is further connected to a load driving module and used to output an inverse control signal to said load driving module. An air conditioner comprising the power factor correction circuit according to any one of claims 1 to 10.

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