PFC totem pole circuit and ZVS implementation method

Abstract

The present application provides a PFC totem pole circuit and a ZVS implementation method. The PFC totem pole circuit comprises an alternating-current power supply, an inductor, a first switch transistor, a second switch transistor, a third switch transistor, a fourth switch transistor, a current acquisition module, a voltage acquisition module, and a capacitor, wherein the third switch transistor is a main transistor and the fourth switch transistor is a flyback diode, or the fourth switch transistor is a main transistor and the third switch transistor is a flyback diode, the current acquisition module is connected in series with the inductor and the alternating-current power supply, the voltage acquisition module is connected in parallel with the inductor, the current acquisition module is configured to acquire an inductor current signal of the inductor, the inductor current signal is used for controlling the flyback diode, the voltage acquisition module is configured to acquire an inductor voltage signal of the inductor, and the inductor voltage signal is used for controlling the main transistor.

Description

PFC Totem Pole Circuit and ZVS Implementation Method

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to a Chinese patent application filed with the Patent Office of China on August 24, 2023, with application number 202311080297.2 and invention name “PFC Totem Pole Circuit and ZVS Implementation Method”. The entire contents of the Chinese patent application are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of circuit control technology, and in particular to a power factor correction (PFC) totem pole circuit and a zero voltage switch (ZVS) implementation method. Background Art

[0004] A PFC totem-pole circuit converts AC power to DC. Typically, a PFC totem-pole circuit includes an AC power source, an inductor, a capacitor, a main circuit, and a freewheeling diode. During operation, the main circuit and the freewheeling diode alternately switch on and off, converting the input AC power to DC output.

[0005] Traditional bridgeless totem-pole PFC circuits suffer from hard-on switching of the switch, resulting in high switching losses. To improve efficiency and reduce switching losses, one solution is to implement zero-voltage switching (ZVS) on the switch. However, traditional critical current mode PFC control can only achieve valley voltage switching, not zero voltage switching.

[0006] Summary of the Invention

[0007] In a first aspect, a PFC totem pole circuit is provided, comprising an AC power supply, an inductor, a first switching tube, a second switching tube, a third switching tube, a fourth switching tube, a current acquisition module, a voltage acquisition module, and a capacitor. One side of the AC power supply is connected to the first end of the first switching tube and the first end of the second switching tube, respectively. The other side of the AC power supply is connected to the first end of the third switching tube and the first end of the fourth switching tube, respectively, through the current acquisition module and the inductor. The second end of the third switching tube is connected to the second end of the first switching tube, and the second end of the fourth switching tube is connected to the second end of the second switching tube. The voltage acquisition module is connected in parallel with the inductor, and the capacitor is connected in parallel with the third and fourth switching tubes. The current acquisition module is configured to acquire an inductor current signal of the inductor, and the voltage acquisition module is configured to acquire an inductor voltage signal of the inductor. The inductor current signal is used to control a freewheeling tube, and the inductor voltage signal is used to control a main tube. Alternatively, the third switching tube is the main tube, and the fourth switching tube is the freewheeling tube, or the fourth switching tube is the main tube, and the third switching tube is the freewheeling tube.

[0008] In a second aspect, a ZVS implementation method is provided, which is applied to the PFC totem pole circuit as described in the first aspect. The method includes: collecting the inductor current signal of the inductor through the current acquisition module; collecting the inductor voltage signal of the inductor through the voltage acquisition module; controlling the freewheeling diode according to the inductor current signal, and controlling the main diode according to the inductor voltage signal.

[0009] According to a third aspect, an electronic device is provided, comprising: a processor; and a memory for storing instructions executable by the processor; wherein the processor is configured to execute the instructions to implement the method described in the second aspect.

[0010] In a fourth aspect, a computer-readable storage medium is provided. When the instructions in the storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the method described in the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in this application or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0012] FIG1 is a schematic structural diagram of a PFC totem pole circuit in the prior art;

[0013] FIG2 is a schematic structural diagram of a PFC totem pole circuit according to an embodiment of the present application;

[0014] FIG3 is a schematic structural diagram of a PFC totem pole circuit according to an embodiment of the present application;

[0015] FIG4 is a schematic structural diagram of a PFC totem pole circuit according to an embodiment of the present application;

[0016] FIG5 is a flow chart of a ZVS implementation method according to an embodiment of the present application;

[0017] FIG6 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

[0018] FIG7 is a schematic structural diagram of a ZVS implementation apparatus according to an embodiment of the present application. DETAILED DESCRIPTION

[0019] In order to help those skilled in the art better understand the technical solutions of this application, the following will clearly and completely describe the technical solutions of this application in conjunction with the drawings of one or more embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0020] The terms "first," "second," and the like in this application and the claims are used to distinguish similar objects and are not used to describe a particular order or precedence. It should be understood that such terms are interchangeable where appropriate so that this application can be implemented in sequences other than those illustrated or described herein. In addition, the term "and / or" in this application and the claims refers to at least one of the connected objects, and the character " / " generally indicates that the connected objects are in an "or" relationship.

[0021] Traditional bridgeless totem-pole circuits suffer from hard-on switching of the switching tubes, resulting in high switching losses. Figure 1 shows a schematic diagram of the structure of a conventional PFC totem-pole circuit. The totem-pole circuit shown in Figure 1 includes an AC power supply (VAC), power-frequency return tubes VT1 and VT2, an inductor L, main power tubes VT3 and VT4, and a bus capacitor C. During the positive half-cycle of the AC power supply (VAC), VT2 is on, VT1 is off, VT4 serves as the main current tube, and VT3 serves as the freewheeling current tube. During the negative half-cycle of the AC power supply (VAC), VT1 is on, VT2 is off, VT3 serves as the main current tube, and VT4 serves as the freewheeling current tube. VT3 and VT4 can be controlled to alternately switch on during both the positive and negative half-cycles of the AC power supply. These alternating switches can convert the AC power supply into a DC output.

[0022] In related technologies, when controlling the alternating switching of VT3 and VT4, there is the problem of hard-on of VT3 and VT4. However, in practical applications, since the operating frequency of the main switch (in the positive half-cycle of the AC power supply, the main switch is VT4, and in the negative half-cycle of the AC power supply, the main switch is VT3) is usually relatively high (up to several hundred kHz), therefore, in the case of hard-on, it will cause large switching losses of the main switch. To reduce the switching losses of the main switch, one solution is to achieve full-range ZVS for the main switch, that is, to achieve zero voltage switching of the main switch every time the main switch is turned on. However, current control methods can usually only achieve ZVS for a part of the main switch range, and cannot achieve ZVS for the entire range.

[0023] The present invention provides a PFC totem-pole circuit and a method for achieving zero-voltage switching (ZVS). By adding a current acquisition module and a voltage acquisition module to the PFC totem-pole circuit, the current acquisition module acquires the inductor current signal, while the voltage acquisition module acquires the inductor voltage signal. The freewheeling diode is then controlled based on the inductor current signal, while the main diode is controlled based on the inductor voltage signal. This allows for precise control of the main diode and freewheeling diode using the acquired signals, achieving full-range zero-voltage switching (ZVS) for the switching diode and effectively reducing switching losses.

[0024] It should be noted that the ZVS implementation method provided in the embodiments of the present application can achieve full-range ZVS for the main circuit. Furthermore, because the full-range ZVS of the main circuit is affected by the freewheeling diode, the embodiments of the present application, while controlling the main circuit, also control the freewheeling diode. That is, while collecting the inductor voltage signal and controlling the main circuit based on the inductor voltage signal, the inductor current signal is also collected and controlled based on the freewheeling diode. Thus, the collected signals can be used to precisely control the main circuit and the freewheeling diode, thereby achieving full-range ZVS for the main circuit and effectively reducing switching losses.

[0025] The following describes in detail the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0026] Figure 2 is a schematic diagram of a PFC totem-pole circuit according to one embodiment of the present application. The PFC totem-pole circuit shown in Figure 2 includes an AC power supply Vac, an inductor L, a first switching transistor VT1, a second switching transistor VT2, a third switching transistor VT3, a fourth switching transistor VT4, a current acquisition module, a voltage acquisition module, and a capacitor C. The connections between these components are as follows:

[0027] One side of the AC power source Vac (i.e., the left side of Vac as shown in FIG2 ) is connected to the first end of the first switching tube VT1 (i.e., terminal 1 as shown in FIG2 ) and the first end of the second switching tube VT2 (i.e., terminal 3 as shown in FIG2 ), respectively. The other side of the AC power source Vac (i.e., the right side of Vac as shown in FIG2 ) is connected to the first end of the third switching tube VT3 (i.e., terminal 5 as shown in FIG2 ) and the first end of the fourth switching tube VT4 (i.e., terminal 7 as shown in FIG2 ) via a current acquisition module and an inductor L, respectively. The second end of the third switching tube VT3 (i.e., terminal 6 as shown in FIG2 ) is connected to the second end of the first switching tube VT1 (i.e., terminal 2 as shown in FIG2 ), and the second end of the fourth switching tube VT4 (i.e., terminal 8 as shown in FIG2 ) is connected to the second end of the second switching tube VT2 (i.e., terminal 4 as shown in FIG2 ). The voltage acquisition module is connected in parallel with the inductor L, and the capacitor C is connected in parallel with the third switching tube VT3 and the fourth switching tube VT4. The current acquisition module can be used to acquire the inductor current signal of inductor L, and the voltage acquisition module can be used to acquire the inductor voltage signal of inductor L. The inductor current signal can be used to control the freewheeling transistor, and the inductor voltage signal can be used to control the main transistor. The third switching transistor VT3 is the main transistor, and the fourth switching transistor VT4 is the freewheeling transistor, or the fourth switching transistor VT4 is the main transistor, and the third switching transistor VT3 is the freewheeling transistor.

[0028] The first and second switching transistors VT1 and VT2 can be power-frequency return transistors, while the third and fourth switching transistors VT3 and VT4 serve as main power transistors. During operation of the PFC totem-pole circuit, the third and fourth switching transistors VT3 and VT4 are alternately switched on. Specifically, during the positive half-cycle of the AC power supply Vac, the second switching transistor VT2 is switched on and the first switching transistor VT1 is switched off. At this time, the fourth switching transistor VT4 functions as the main current transistor, while the third switching transistor VT3 functions as the freewheeling current transistor. The inductor current signal controls the third switching transistor VT3, while the inductor voltage signal controls the fourth switching transistor VT4, causing the third and fourth switching transistors VT3 and VT4 to alternately switch on. During the negative half-cycle of the AC power supply Vac, the first switching transistor VT1 is switched on and the second switching transistor VT2 is switched off. At this time, the third switching transistor VT3 functions as the main current transistor, while the fourth switching transistor VT4 functions as the freewheeling current transistor. The inductor current signal controls the fourth switching transistor VT4, while the inductor voltage signal controls the third switching transistor VT3, causing the third and fourth switching transistors VT3 and VT4 to alternately switch on. When the third switch tube VT3 and the fourth switch tube VT4 are turned on alternately, the AC power source Vac can be converted into a DC power output, that is, DC power is output across the capacitor C.

[0029] The PFC totem-pole circuit provided in the embodiments of the present application adds a current acquisition module and a voltage acquisition module to the PFC totem-pole circuit. The current acquisition module acquires the inductor current signal, and the voltage acquisition module acquires the inductor voltage signal. The freewheeling diode is then controlled based on the inductor current signal, and the main tube is controlled based on the inductor voltage signal. This allows precise control of the main tube and freewheeling diode using the acquired signals. This allows full-range zero-voltage switching (ZVS) to be achieved while precisely controlling both the main tube and the freewheeling diode, effectively reducing switching losses. The full-range ZVS here refers to full-range ZVS for the main tube.

[0030] Optionally, in one implementation, the current acquisition module may include a shunt and a first signal sampling circuit, wherein the shunt is connected in series with the inductor, and the first signal sampling circuit is connected in parallel with the shunt. The shunt may be a resistor, the resistance of which may be set according to actual needs. The first signal sampling circuit may be used to acquire the voltage across the shunt. This voltage may be processed by the first sampling circuit to obtain the inductor current signal, or may be processed by other modules to obtain the inductor current signal. In other possible implementations, the current acquisition module may also have other structures, as long as they can achieve the acquisition of the inductor current signal. Examples of other structures are not provided here.

[0031] Optionally, in one implementation, the voltage acquisition module may include an auxiliary winding and a second signal sampling circuit, the auxiliary winding is coupled to the inductor, and the second signal sampling circuit is connected in parallel to the auxiliary winding. The winding direction of the auxiliary winding may be the same as or different from the winding direction of the inductor, and the auxiliary winding may reflect the voltage condition of the inductor. The second signal sampling circuit may be used to acquire two voltages corresponding to the two endpoints of the auxiliary winding. The two voltages may be processed by the second sampling circuit to obtain an inductor voltage signal, or may be processed by other modules to obtain an inductor voltage signal. In other possible implementations, the voltage acquisition module may also be other structures, as long as the acquisition of the inductor voltage signal can be achieved. Other structures will not be illustrated one by one here.

[0032] Optionally, the PFC totem pole circuit provided in the embodiments of the present application may further include a driver module. The driver module's input terminal may be connected to the output terminal of the current acquisition module and the output terminal of the voltage acquisition module, respectively, and the driver module's output terminal may be connected to the control terminal of the third switch tube and the control terminal of the fourth switch tube, respectively. The driver module may be configured to control the freewheeling transistor based on the inductor current signal and the main transistor based on the inductor voltage signal. Specifically, during the positive half-cycle of the AC power supply, the driver module may be configured to control the third switch tube, serving as the freewheeling transistor, based on the inductor current signal and the fourth switch tube, serving as the main transistor, based on the inductor voltage signal. During the negative half-cycle of the AC power supply, the driver module may be configured to control the fourth switch tube, serving as the freewheeling transistor, based on the inductor current signal and the third switch tube, serving as the main transistor, based on the inductor voltage signal.

[0033] In one implementation, if the signals output by the current acquisition module and the voltage acquisition module are both voltage signals, the drive module may include a processor and a drive circuit. The processor is configured to process the voltage signal output by the current acquisition module to obtain an inductor current signal, and to process the voltage signal output by the voltage acquisition module to obtain an inductor voltage signal, and to determine whether to send a drive signal to the drive circuit based on the inductor current signal and the inductor voltage signal. The drive circuit is configured to control the main inductor and the freewheeling diode based on the drive signal sent by the processor, for example, controlling when the main inductor is turned on and when the freewheeling diode is turned off based on the drive signal. In another implementation, if the signal output by the current acquisition module is an inductor current signal and the signal output by the voltage acquisition module is an inductor voltage signal, the drive module may also include a processor and a drive circuit. The processor is configured to receive the inductor current signal and the inductor voltage signal, and to determine whether to send a drive signal to the drive circuit based on the received inductor current signal and the inductor voltage signal. The drive circuit is configured to control the main inductor and the freewheeling diode based on the drive signal sent by the processor, for example, controlling when the main inductor is turned on and when the freewheeling diode is turned off based on the drive signal.

[0034] Figure 3 is a schematic diagram of the structure of a PFC totem pole circuit according to an embodiment of the present application. As shown in Figure 3, the PFC totem pole circuit includes an AC power supply (VAC), four switching transistors (VT1, VT2, VT3, and VT4), a capacitor (C), a resistor (R), an inductor (L), an auxiliary winding (LO), a first signal sampling circuit, a second signal sampling circuit, a processor, and a drive circuit. One side of the AC power supply (VAC) is connected to the midpoint between VT1 and VT2, and the other side is connected to the midpoint between VT3 and VT4 via resistor (R) and inductor (L). Capacitor (C) is connected in parallel with VT3 and VT4. The first signal sampling circuit is connected in parallel with resistor (R) and is responsible for sampling the voltage across resistor (R) and outputting it to the processor, which processes it to obtain an inductor current signal. The auxiliary winding (LO) is coupled to inductor (L). A second signal sampling circuit is connected in parallel with the auxiliary winding (LO) and is responsible for sampling the two voltages at the two endpoints of the auxiliary winding and outputting them to the processor, which processes them to obtain an inductor voltage signal. The input end of the drive circuit is connected to the output end of the processor, and the output end of the drive circuit is connected to the control ends of VT3 and VT4 respectively. In the positive half cycle of Vac, the drive circuit is used to control VT3 according to the inductor current signal and to control VT4 according to the inductor voltage signal. In the negative half cycle of Vac, the drive circuit is used to control VT4 according to the inductor current signal and to control VT3 according to the inductor voltage signal.

[0035] Optionally, if the first signal sampling circuit shown in FIG3 can process the collected voltage signal and obtain the inductor current signal, and the second signal sampling circuit can process the collected voltage signal and obtain the inductor voltage signal, then the PFC totem pole circuit shown in FIG3 may not include a processor, that is, the output end of the first signal sampling circuit and the output end of the second signal sampling circuit may be directly connected to the input end of the drive circuit.

[0036] In the embodiments of the present application, the PFC totem-pole circuits shown in Figures 2 and 3 are both single-phase circuits. In one possible implementation, the PFC totem-pole circuit can also be a multi-phase circuit, where each phase circuit includes an inductor, a current acquisition module, a voltage acquisition module, a third switching transistor, and a fourth switching transistor, and each phase circuit has the same circuit structure. A multi-phase PFC totem-pole circuit can achieve high power, thereby meeting high-power requirements. To reduce ripple in the output DC power, the drive signals of the multi-phase circuit can have a certain phase difference. Optionally, the phase difference between the drive signal of the Nth phase circuit and the drive signal of the N-1th phase circuit can be 2π / N. The drive signals include an inductor current signal and an inductor voltage signal, where N is an integer greater than 1. For example, when N=2, the two phases are interleaved, the circuit structure of the second phase is the same as that of the first phase, and the phase of the drive signal of the second phase circuit lags behind the drive signal of the first phase circuit by 2*π / 2=180°; when N=3, the three phases are interleaved, the phase of the drive signal of the second phase circuit lags behind the drive signal of the first phase circuit by 2*π / 3=120°, the phase of the drive signal of the third phase circuit lags behind the drive signal of the second phase circuit by 2*π / 3=120°, and lags behind the drive signal of the first phase circuit by 2*2*π / N=240°; when N≥4, the same applies.

[0037] To facilitate understanding of a multi-phase PFC totem-pole circuit, please refer to Figure 4 . Figure 4 is a schematic diagram of the structure of a PFC totem-pole circuit according to one embodiment of the present application. The PFC totem-pole circuit shown in Figure 4 is a two-phase circuit. The first phase circuit includes a resistor R1, a first signal sampling circuit, an inductor L1, an auxiliary winding L0, a second signal sampling circuit, and switches VT3 and VT4. The second phase circuit includes a resistor R2, a third signal sampling circuit, an inductor L3, an auxiliary winding L2, a fourth signal sampling circuit, and switches VT5 and VT6. The processor, the drive circuit, the switches VT1 and VT2, the AC power supply Vac, and the capacitor C are common components to both the first and second phase circuits. In Figure 4 , the phase of the drive signal for the first phase circuit lags by 180° relative to the phase of the drive signal for the second phase circuit.

[0038] The PFC totem-pole circuit provided in the embodiments of the present application adds a current acquisition module and a voltage acquisition module to the circuit. The current acquisition module acquires the inductor current signal, and the voltage acquisition module acquires the inductor voltage signal. The freewheeling diode is then controlled based on the inductor current signal, and the main diode is controlled based on the inductor voltage signal. This allows for precise control of both the main diode and the freewheeling diode, thereby achieving full-range zero-voltage switching (ZVS) and effectively reducing switching losses. Furthermore, since each phase circuit can acquire both the inductor voltage and current using a single current acquisition module and a voltage acquisition module, circuit components can be reduced, saving costs.

[0039] Based on the PFC totem pole circuit provided in the embodiment of the present application, the embodiment of the present application also provides a ZVS implementation method applied to the PFC totem pole circuit. Based on this ZVS implementation method, full-range ZVS can be achieved. For details, see Figure 5.

[0040] FIG5 is a flow chart of a ZVS implementation method according to an embodiment of the present application. The ZVS implementation method shown in FIG5 can be applied to any of the PFC totem pole circuits shown in FIG2 to FIG4. The ZVS implementation method shown in FIG5 is described as follows.

[0041] S502: Collect an inductor current signal of the inductor through a current collection module.

[0042] During the operation of the PFC totem pole circuit, the inductor current signal of the inductor in the circuit can be collected by the current collection module in the circuit.

[0043] In one implementation, the current acquisition module may include a shunt and a first signal sampling circuit, wherein the shunt is connected in series with the inductor, and the first signal sampling circuit is connected in parallel with the shunt. When the current acquisition module is used to acquire the inductor current signal of the inductor, the following may be included:

[0044] A first voltage across the shunt is collected by a first signal sampling circuit; the first voltage is processed to obtain an inductor current signal.

[0045] Since the shunt and the inductor are in a series relationship, the voltage across the shunt can indirectly reflect the current flowing through the inductor. Therefore, the first voltage across the shunt can be collected by the first signal sampling circuit, and then the inductor current signal can be obtained based on the first voltage processing.

[0046] Processing the first voltage to obtain the inductor current signal can be accomplished in two ways. The first way is to compare the first voltage with a preset second voltage and determine the inductor current signal based on the comparison result. The second way is to determine the current signal flowing through the shunt (i.e., the instantaneous value of the current flowing through the inductor) based on the first voltage and the resistance value of the shunt, and determine this current signal as the inductor current signal. In the first embodiment, the inductor current signal is a PWM signal, which may include a high-level signal, a low-level signal, a rising-edge signal, and a falling-edge signal. When the first voltage is greater than the second voltage, the inductor current signal is a high-level signal; when the first voltage is less than the second voltage, the inductor current signal is a low-level signal. When the low-level signal switches to a high-level signal, the inductor current signal is a rising-edge signal, indicating that the inductor current is at a sudden change from a low level (where the first voltage is less than the second voltage) to a high level (where the first voltage is greater than the second voltage). When the high-level signal switches to a low-level signal, the inductor current signal is a falling-edge signal, indicating that the inductor current is at a sudden change from a high level (where the first voltage is greater than the second voltage) to a low level (where the first voltage is less than the second voltage). The second voltage can be set based on actual conditions, as long as it ensures that full-range ZVS switching of the main circuit can be achieved when the freewheeling diode is controlled according to the inductor current signal. For example, the second voltage can be the voltage across the shunt when the main circuit achieves ZVS switching.

[0047] S504: Collect an inductor voltage signal of the inductor through a voltage collection module.

[0048] During the operation of the PFC totem pole circuit, the inductor voltage signal of the inductor in the circuit can be collected by the voltage collection module in the circuit.

[0049] In one implementation, the voltage acquisition module may include an auxiliary winding and a second signal sampling circuit, wherein the auxiliary winding is coupled to the inductor, and the second signal sampling circuit is connected in parallel with the auxiliary winding. When the voltage acquisition module is used to acquire the inductor voltage signal, the following may be included:

[0050] The third voltage and the fourth voltage at the two end points of the auxiliary winding are collected by the second signal sampling circuit; the third voltage is compared with the fourth voltage, and the inductor voltage signal is determined according to the comparison result.

[0051] Because the auxiliary winding is coupled to the inductor, the voltage across the auxiliary winding can indirectly reflect the voltage across the inductor. Therefore, the voltages at the two endpoints of the auxiliary winding, i.e., the third voltage and the fourth voltage, can be collected by the second signal sampling circuit. Then, by comparing the third voltage and the fourth voltage, an inductor voltage signal can be obtained. The inductor voltage signal can be a PWM signal. When the third voltage is greater than the fourth voltage, the inductor voltage signal is a high-level signal. When the third voltage is less than the fourth voltage, the inductor voltage signal is a low-level signal. When the low-level signal switches to a high-level signal, the inductor voltage signal is a rising-edge signal, indicating the time point at which the inductor voltage suddenly changes from a falling state to a rising state. When the high-level signal switches to a low-level signal, the inductor voltage signal is a falling-edge signal, indicating the time point at which the inductor voltage suddenly changes from a rising state to a falling state.

[0052] S506: Control the freewheeling diode according to the inductor current signal, and control the main diode according to the inductor voltage signal.

[0053] After acquiring the inductor voltage and current signals, the freewheeling diode in the circuit can be controlled based on the inductor current signal, and the main diode in the circuit can be controlled based on the inductor voltage signal. For example, in the PFC totem pole circuits shown in Figures 2 and 3, during the positive half-cycle of the AC power supply Vac, VT3 can be controlled based on the inductor current signal, and VT4 can be controlled based on the inductor voltage signal. During the negative half-cycle of the AC power supply Vac, VT4 can be controlled based on the inductor current signal, and VT3 can be controlled based on the inductor voltage signal.

[0054] In one implementation, controlling the freewheeling diode according to the inductor current signal and controlling the main diode according to the inductor voltage signal may include:

[0055] When the freewheeling tube is turned off, the main tube is controlled to be turned on according to the inductor voltage signal; when the main tube is turned off, the freewheeling tube is turned on according to the preset dead time; when the freewheeling tube is turned on, the freewheeling tube is controlled to be turned off according to the inductor current signal.

[0056] In an embodiment of the present application, in the initial stage of the positive half cycle and the negative half cycle of the AC power supply, the freewheeling tube and the main tube are both in the default off (i.e. cut-off) state. Afterwards, the freewheeling tube and the main tube can be controlled according to the inductor current signal and the inductor voltage signal, so as to alternately open the main tube and the freewheeling tube. Specifically, taking the positive half cycle of the AC power supply as an example, when both the main tube and the freewheeling tube are turned off, the main tube can be turned on first. When the main tube is turned on, the main tube can be controlled to be turned on according to the inductor voltage signal. Afterwards, the main tube can be controlled to be turned off. When the main tube is turned off, the freewheeling tube can be controlled to be turned on. When the freewheeling tube is turned on, the freewheeling tube can be turned on according to the preset dead time, that is, when the time of turning off the main tube reaches the dead time, the freewheeling tube can be controlled to be turned on. After the freewheeling tube is turned on, the freewheeling tube can be turned off. When the freewheeling tube is turned off, the freewheeling tube can be controlled to be turned off according to the inductor current signal. When the freewheeling diode is off, the main diode can be turned on based on the inductor voltage signal, and so on. This cycle repeats, allowing the main diode and freewheeling diode to be alternately turned on during the positive half-cycle of the AC power supply, controlled by the inductor voltage signal and the inductor current signal. During the negative half-cycle of the AC power supply, the main diode and freewheeling diode can be turned on and off using the same method. This allows precise control of when the main diode is turned on based on the collected inductor voltage signal, and when the freewheeling diode is turned off based on the collected inductor current signal. This allows full-range ZVS of the main diode to be achieved during both the positive and negative half-cycles of the AC power supply.

[0057] In the above control method, when the main pipe is turned on and off according to the inductor voltage signal, the method may include:

[0058] Determine the start time of the supervisor; when the start time is reached, shut down the supervisor.

[0059] The main circuit's on-time can be determined based on circuit parameters of the PFC totem-pole circuit. These circuit parameters may include at least one of the PFC totem-pole circuit's input voltage, bus voltage, inductance, and phase-locked loop (PLL) value. The specific implementation of determining the main circuit's on-time based on these circuit parameters can be found in related art and will not be detailed here.

[0060] After the opening time of the supervisor is determined, when the supervisor opening time reaches the opening time, the supervisor can be controlled to be shut down.

[0061] As previously mentioned, the inductor voltage signal can include high-level signals, low-level signals, rising-edge signals, and falling-edge signals. In the aforementioned control method, when controlling the main circuit breaker based on the inductor voltage signal, two control methods can be used. The first control method controls the main circuit breaker based on the high-level and low-level signals in the inductor voltage signal, while the second control method controls the main circuit breaker based on the rising-edge and falling-edge signals in the inductor voltage signal. The specific control method used to control the main circuit breaker breaker can be determined based on the actual circuit design and is not specifically limited here.

[0062] When controlling the main circuit to be turned on based on high-level and low-level signals in the inductor voltage signal, the main circuit may be controlled to be turned on when the inductor voltage signal is detected as a high-level signal during the positive half-cycle of the AC power supply, and controlled to be turned on when the inductor voltage signal is detected as a low-level signal during the negative half-cycle of the AC power supply. Alternatively, the main circuit may be controlled to be turned on when the inductor voltage signal is detected as a low-level signal during the positive half-cycle of the AC power supply, and controlled to be turned on when the inductor voltage signal is detected as a high-level signal during the negative half-cycle of the AC power supply. The specific control can be determined based on the circuit design of the voltage acquisition module in the PFC totem pole circuit, for example, based on whether the winding direction of the auxiliary winding is consistent with the winding direction of the inductor.

[0063] When controlling the main circuit to be turned on based on the rising and falling edge signals in the inductor voltage signal, the main circuit may be controlled to be turned on when a rising edge signal is detected in the inductor voltage signal during the positive half cycle of the AC power supply, and to be turned on when a falling edge signal is detected in the inductor voltage signal during the negative half cycle of the AC power supply. Alternatively, the main circuit may be controlled to be turned on when a falling edge signal is detected in the inductor voltage signal during the positive half cycle of the AC power supply, and to be turned on when a rising edge signal is detected in the negative half cycle of the AC power supply. The specific control can be determined based on the circuit design of the voltage acquisition module in the PFC totem pole circuit, for example, based on whether the winding direction of the auxiliary winding is consistent with the winding direction of the inductor.

[0064] As previously mentioned, the inductor current signal may include a high-level signal, a low-level signal, a rising edge signal, and a falling edge signal, or the inductor current signal may be a current signal. In the above-described control method, when controlling the freewheeling diode to be turned off based on the inductor current signal, three control modes may be included. The first control mode is to control the freewheeling diode to be turned off based on the high-level and low-level signals in the inductor current signal; the second control mode is to control the freewheeling diode to be turned off based on the rising edge and falling edge signals in the inductor current signal; and the third control mode is to control the freewheeling diode to be turned off when the current signal reaches a preset current value. Specifically, when the inductor circuit signal includes a high-level signal, a low-level signal, a rising edge signal, and a falling edge signal, whether to use the first control mode or the second control mode to control the main diode to be turned on can be determined based on the actual circuit design and is not specifically limited here.

[0065] When controlling the freewheeling diode to shut down based on high-level and low-level signals in the inductor current signal, the freewheeling diode may be controlled to shut down when the inductor current signal is detected as a high-level signal during the positive half-cycle of the AC power supply, and to shut down when the inductor current signal is detected as a low-level signal during the negative half-cycle of the AC power supply. Alternatively, the freewheeling diode may be controlled to shut down when the inductor current signal is detected as a low-level signal during the positive half-cycle of the AC power supply, and to shut down when the inductor current signal is detected as a high-level signal during the negative half-cycle of the AC power supply. The specific control can be determined based on the circuit design of the current acquisition module in the PFC totem pole circuit, for example, by comparing the collected first voltage with the preset second voltage, i.e., by subtracting the second voltage from the first voltage or the second voltage from the first voltage. It should be noted that the value of the preset second voltage is not fixed and may vary based on the actual operating conditions of the prototype, such as the positive and negative half-cycles of the AC power supply, the input voltage, the output power, and the bus voltage.

[0066] When controlling the freewheeling diode to shut down based on the rising and falling edge signals in the inductor current signal, the freewheeling diode may be controlled to shut down when the inductor current signal is detected as a rising edge signal during the positive half cycle of the AC power supply, and to shut down when the inductor current signal is detected as a falling edge signal during the negative half cycle of the AC power supply. Alternatively, the freewheeling diode may be controlled to shut down when the inductor current signal is detected as a falling edge signal during the positive half cycle of the AC power supply, and to shut down when the inductor current signal is detected as a rising edge signal during the negative half cycle of the AC power supply. This may be determined based on the circuit design of the current acquisition module in the PFC totem pole circuit, for example, based on whether the first voltage minus the second voltage or the second voltage minus the first voltage is used when comparing the collected first voltage with the preset second voltage. It should be noted that the value of the preset second voltage is not fixed and may vary based on the actual operating conditions of the prototype, such as the positive and negative half cycles of the AC power supply, input voltage, output power, bus voltage, and so on.

[0067] When the freewheeling diode is controlled to be turned off according to the current signal, the freewheeling diode may be controlled to be turned off when the current signal reaches a preset current value. The preset current value may be a current value flowing through the inductor when the full range ZVS of the main tube is achieved.

[0068] In the embodiment of the present application, the inductor voltage signal is used to control the main tube to be turned on, and the inductor current signal is used to control the freewheeling tube to be turned off. The principle of achieving full-range ZVS of the main tube is as follows:

[0069] The inductor voltage signal can represent the voltage across the inductor. Controlling the main circuit to turn on when the inductor voltage signal is high or low, or when the inductor voltage signal is rising or falling, can ensure that the main circuit is turned on when the voltage across the inductor reverses, at which point the voltage across the main circuit is zero, thereby achieving zero-voltage switching (ZVS) of the main circuit. The inductor current signal can represent the current flowing through the inductor. Controlling the freewheeling diode to turn off when the inductor current signal is high or low, or when the inductor current signal is rising or falling, or when the current signal reaches a preset value can ensure that the current flowing through the inductor reaches a preset value. At this point, the resonance of the inductor and capacitor in the circuit can resonate the voltage across the main circuit to zero, thereby achieving zero-voltage switching of the main circuit.

[0070] To facilitate understanding of the ZVS implementation method provided in the embodiments of the present application, the control process of the main tube and the freewheeling tube will be described in detail below, taking the PFC totem pole circuit shown in FIG3 as an example.

[0071] In the PFC totem pole circuit shown in Figure 3, when the AC power supply Vac is in the positive half cycle, VT2 is turned on, VT1 is turned off, VT4 is the main tube, and VT3 is the freewheeling tube. When the AC power supply Vac is in the negative half cycle, VT1 is turned on, VT2 is turned off, VT3 is the main tube, and VT4 is the freewheeling tube.

[0072] At the initial stage of the positive half cycle of the AC power supply Vac, the drive circuit controls the shutoff of the main tube VT4 and the freewheeling tube VT3, that is, the main tube VT4 and the freewheeling tube VT3 are in the shutoff state by default. Afterwards, when controlling the main tube VT4 and the freewheeling tube VT3, the control flow is as follows:

[0073] Step 1: The processor receives the voltage signal output by the second signal sampling circuit, determines the inductor voltage signal according to the voltage signal, and outputs the inductor voltage signal to the drive circuit. The drive circuit controls the main tube VT4 to open according to the inductor voltage signal.

[0074] Step 2: The processor calculates the on-time T1 of the main VT4 based on the input voltage (Vac), BUS voltage (i.e., the voltage across the capacitor shown in Figure 3), inductance (the inductor L), phase-locked loop information, and outputs T1 to the drive circuit.

[0075] Step 3: After the on-time of main tube VT4 reaches T1, the driving circuit controls main tube VT4 to turn off.

[0076] Step 4: The driving circuit controls the opening of the freewheeling tube VT3 according to the preset dead time, that is, after the driving circuit controls the closing of the main tube VT4, when the closing time reaches the preset dead time, the freewheeling tube VT3 is controlled to be opened.

[0077] Step 5: The processor receives the voltage signal output by the first signal sampling circuit, determines the inductor current signal according to the voltage signal, and outputs the inductor current signal to the drive circuit. The drive circuit controls the turn-off of the freewheeling tube VT3 according to the inductor current signal.

[0078] Step 6: After the drive circuit controls the freewheeling tube VT3 to be turned off, the process can return to step 1, that is, controlling the main tube VT4 to be turned on according to the inductor voltage signal.

[0079] In the positive half cycle of the AC power supply Vac, VT3 and VT4 can be opened alternately by cyclically executing the above steps 1 to 6. When VT3 and VT4 are opened alternately, the AC power supply can be converted into a DC output.

[0080] At the initial stage of the negative half cycle of the AC power supply Vac, the drive circuit controls the shutoff of the main tube VT3 and the freewheeling tube VT4, that is, the main tube VT3 and the freewheeling tube VT4 are in the shutoff state by default. Afterwards, when controlling the main tube VT3 and the freewheeling tube VT4, the control flow is as follows:

[0081] Step 7: The processor receives the voltage signal output by the second signal sampling circuit, determines the inductor voltage signal according to the voltage signal, and outputs the inductor voltage signal to the drive circuit. The drive circuit controls the main tube VT3 to be turned on according to the inductor voltage signal.

[0082] Step 8: The processor calculates the on-time T2 of the main VT3 based on the input voltage (Vac), BUS voltage (i.e., the voltage across the capacitor shown in FIG3 ), inductance (the inductance of the inductor L), phase-locked loop (PLL) and other information, and outputs T2 to the drive circuit.

[0083] Step 9: After the on-time of main tube VT3 reaches T2, the driving circuit controls main tube VT3 to be turned off.

[0084] Step 10: The driving circuit controls the freewheeling tube VT4 to be turned on according to the preset dead time. That is, after the driving circuit controls the main tube VT3 to be turned off, when the off time reaches the preset dead time, the driving circuit controls the freewheeling tube VT4 to be turned on.

[0085] Step 11: The processor receives the voltage signal output by the first signal sampling circuit, determines the inductor current signal according to the voltage signal, and outputs the inductor current signal to the drive circuit. The drive circuit controls the turn-off of the freewheeling tube VT4 according to the inductor current signal.

[0086] Step 12: After the drive circuit controls the freewheeling tube VT4 to be turned off, the process may return to step 7, that is, controlling the main tube VT3 to be turned on according to the inductor voltage signal.

[0087] In the negative half cycle of the AC power supply Vac, VT3 and VT4 can be opened alternately by cyclically executing the above steps 7 to 12. When VT3 and VT4 are opened alternately, the AC power supply can be converted into a DC output.

[0088] Based on the above control process, the main circuit can be precisely controlled to turn on based on the collected inductor voltage signal, and the freewheeling diode can be precisely controlled to turn off based on the collected inductor current signal, both in the positive and negative half-cycles of the AC power supply Vac. Therefore, full-range ZVS of the main circuit can be achieved in both the positive and negative half-cycles of the AC power supply, effectively reducing switching losses.

[0089] Based on the technical solution provided in the embodiments of the present application, by adding a current acquisition module and a voltage acquisition module to the PFC totem pole circuit, and using the current acquisition module to acquire the inductor current signal of the inductor, and using the voltage acquisition module to acquire the inductor voltage signal of the inductor, then controlling the freewheeling tube according to the inductor current signal, and controlling the main tube according to the inductor voltage signal, the main tube and the freewheeling tube can be precisely controlled by the acquired signals, thereby achieving full-range ZVS while precisely controlling the main tube and the freewheeling tube, thereby effectively reducing switching losses.

[0090] The foregoing description describes specific embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in an order different from that described in the embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order shown or the sequential order to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0091] FIG6 is a schematic diagram of the structure of an electronic device according to an embodiment of the present application. Referring to FIG6 , at the hardware level, the electronic device includes a processor, and optionally also includes an internal bus, a network interface, and a memory. The memory may include a memory, such as a high-speed random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage device. Of course, the electronic device may also include hardware required for other services.

[0092] The processor, network interface, and memory can be interconnected via an internal bus, such as an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus. These buses can be classified as address buses, data buses, and control buses. For ease of illustration, FIG6 shows only one bidirectional arrow, but this does not imply that there is only one bus or only one type of bus.

[0093] The memory is used to store programs. Specifically, the program may include program code, which includes computer operating instructions. The memory may include internal memory and non-volatile memory, and provides instructions and data to the processor.

[0094] The processor reads the corresponding computer program from the non-volatile memory into the internal memory and then runs it, forming a ZVS implementation device at the logical level. The processor executes the program stored in the memory and is specifically used to perform the following operations:

[0095] The inductor current signal of the inductor is collected by the current collection module; the inductor voltage signal of the inductor is collected by the voltage collection module; the freewheeling tube is controlled according to the inductor current signal, and the main tube is controlled according to the inductor voltage signal.

[0096] The method performed by the ZVS implementation device disclosed in the embodiment shown in FIG6 of the present application can be applied to a processor or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method can be completed by hardware integrated logic circuits in the processor or by software instructions. The above processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The various methods, steps, and logic block diagrams disclosed in this application can be implemented or executed. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this application can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in the memory, and the processor reads the information in the memory and, in conjunction with its hardware, completes the steps of the above method.

[0097] The electronic device can also execute the method of FIG5 and realize the functions of the ZVS implementation device in the embodiment shown in FIG5 , which will not be described in detail in this application.

[0098] Of course, in addition to software implementation, the electronic device of this application does not exclude other implementation methods, such as logic devices or a combination of software and hardware, etc. That is to say, the execution subject of the following processing flow is not limited to each logic unit, but can also be hardware or logic devices.

[0099] The present application also provides a computer-readable storage medium storing one or more programs, wherein the one or more programs include instructions. When executed by a portable electronic device including multiple application programs, the instructions enable the portable electronic device to perform the method of the embodiment shown in FIG. 5 , and are specifically configured to perform the following operations:

[0100] The inductor current signal of the inductor is collected by the current collection module; the inductor voltage signal of the inductor is collected by the voltage collection module; the freewheeling tube is controlled according to the inductor current signal, and the main tube is controlled according to the inductor voltage signal.

[0101] FIG7 is a schematic diagram of the structure of a ZVS implementation device 70 according to an embodiment of the present application. Referring to FIG7 , in a software implementation, the ZVS implementation device 70 may include: a first signal acquisition module 71, a second signal acquisition module 72, and a control module 73, wherein:

[0102] The first signal acquisition module 71 acquires the inductor current signal of the inductor through the current acquisition module; the second signal acquisition module 72 acquires the inductor voltage signal of the inductor through the voltage acquisition module; the control module 73 controls the freewheeling tube according to the inductor current signal, and controls the main tube according to the inductor voltage signal.

[0103] Optionally, the current acquisition module includes a shunt and a first signal sampling circuit, the shunt is connected in series with the inductor, and the first signal sampling circuit is connected in parallel with the shunt; wherein the first signal acquisition module 71 collects the inductor current signal of the inductor through the current acquisition module, including:

[0104] The first voltage across the shunt is collected by the first signal sampling circuit; the first voltage is processed to obtain the inductor current signal.

[0105] Optionally, the first signal sampling module 71 processes the first voltage to obtain the inductor current signal, including:

[0106] Compare the first voltage with a preset second voltage and determine the inductor current signal based on the comparison result; or, determine the current signal flowing through the shunt based on the first voltage and the resistance value of the shunt; and determine the current signal as the inductor current signal.

[0107] Optionally, the voltage acquisition module includes an auxiliary winding and a second signal sampling circuit, the auxiliary winding is coupled to the inductor, and the second signal sampling circuit is connected in parallel with the auxiliary winding; wherein the second signal acquisition module 71 acquires the inductor voltage signal of the inductor through the voltage acquisition module, including:

[0108] collecting a third voltage and a fourth voltage at two end points of the auxiliary winding by the second signal sampling circuit;

[0109] The third voltage is compared with the fourth voltage, and the inductor voltage signal is determined according to the comparison result.

[0110] Optionally, the control module 73 controls the freewheeling diode according to the inductor current signal, and controls the main diode according to the inductor voltage signal, including:

[0111] When the freewheeling tube is turned off, the main tube is controlled to be turned on according to the inductor voltage signal; when the main tube is turned off, the freewheeling tube is turned on according to the preset dead time; when the freewheeling tube is turned on, the freewheeling tube is controlled to be turned off according to the inductor current signal.

[0112] Optionally, the control module 73, when controlling the main pipe to be opened according to the inductor voltage signal, further includes:

[0113] Determine the opening time of the main pipe; and shut down the main pipe when the opening time is reached.

[0114] Optionally, the control module 73 determines the activation time of the supervisor, including:

[0115] The turn-on time of the main circuit is determined according to circuit parameters of the PFC totem pole circuit, wherein the circuit parameters include at least one of an input voltage, a BUS voltage, an inductance, and a phase-locked loop of the PFC totem pole circuit.

[0116] Optionally, the inductor voltage signal includes a high level signal, a low level signal, a rising edge signal, and a falling edge signal; wherein the control module 73 controls the main pipe to be opened according to the inductor voltage signal, including:

[0117] The main pipe is controlled to be open according to the high level signal and the low level signal; or the main pipe is controlled to be open according to the rising edge signal and the falling edge signal.

[0118] Optionally, the inductor current signal includes a high-level signal, a low-level signal, a rising edge signal, and a falling edge signal, or the inductor current signal is a current signal; wherein the control module 73 controls the freewheeling diode to be turned off according to the inductor current signal, including:

[0119] The freewheeling tube is controlled to be turned off according to the high-level signal and the low-level signal; or, the freewheeling tube is controlled to be turned off according to the rising edge signal and the falling edge signal; or, when the current signal reaches a preset current value, the freewheeling tube is controlled to be turned off.

[0120] The ZVS implementation device 70 provided in the present application can also execute the method of FIG5 and implement the functions of the ZVS implementation device 70 in the embodiment shown in FIG5 , which will not be described in detail in the present application.

[0121] In short, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

[0122] The systems, devices, modules, or units described in the above embodiments may be implemented by computer chips or entities, or by products having certain functions. A typical implementation device is a computer. Specifically, the computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0123] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0124] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0125] The various embodiments in this application are described in a progressive manner. Similar parts between the various embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences between the other embodiments. In particular, the system embodiment is generally similar to the method embodiment, so the description is relatively simple. For relevant parts, refer to the partial description of the method embodiment.

Claims

1. A PFC totem pole circuit, comprising an AC power supply, an inductor, a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a current acquisition module, a voltage acquisition module and a capacitor, wherein: One side of the AC power supply is connected to the first end of the first switch tube and the first end of the second switch tube respectively, the other side of the AC power supply is connected to the first end of the third switch tube and the first end of the fourth switch tube respectively through the current acquisition module and the inductor, the second end of the third switch tube is connected to the second end of the first switch tube, the second end of the fourth switch tube is connected to the second end of the second switch tube, the voltage acquisition module is connected in parallel with the inductor, and the capacitor is connected in parallel with the third switch tube and the fourth switch tube; The current acquisition module is used to acquire the inductor current signal of the inductor, and the voltage acquisition module is used to acquire the inductor voltage signal of the inductor. The inductor current signal is used to control the freewheeling tube, and the inductor voltage signal is used to control the main tube; wherein, the third switch tube is the main tube, and the fourth switch tube is the freewheeling tube, or, the fourth switch tube is the main tube, and the third switch tube is the freewheeling tube.

2. The PFC totem pole circuit according to claim 1, wherein in the positive half cycle of the AC power supply, the second switch tube is turned on, the first switch tube is turned off, the fourth switch tube is the main tube, and the third switch tube is the freewheeling tube; In the negative half cycle of the AC power supply, the first switch tube is turned on, the second switch tube is turned off, the third switch tube is the main switch, and the fourth switch tube is the freewheeling tube.

3. The PFC totem pole circuit according to claim 1, wherein the current acquisition module comprises a shunt and a first signal sampling circuit, the shunt is connected in series with the inductor, and the first signal sampling circuit is connected in parallel with the shunt.

4. The PFC totem pole circuit according to claim 1, wherein the voltage acquisition module comprises an auxiliary winding and a second signal sampling circuit, the auxiliary winding is coupled to the inductor, and the second signal sampling circuit is connected in parallel to the auxiliary winding.

5. The PFC totem pole circuit according to claim 1, further comprising a driving module, wherein an input end of the driving module is respectively connected to an output end of the current acquisition module and an output end of the voltage acquisition module, and an output end of the driving module is respectively connected to a control end of the third switch tube and a control end of the fourth switch tube; in, The driving module is used to control the freewheeling tube according to the inductor current signal, and to control the main tube according to the inductor voltage signal.

6. The PFC totem pole circuit according to any one of claims 1 to 5, wherein the inductor, the current acquisition module, the voltage acquisition module, the third switch tube and the fourth switch tube constitute a single-phase circuit of the PFC totem pole circuit, and the PFC totem pole circuit includes a plurality of the single-phase circuits, and each single-phase circuit has the same circuit structure; in, The phase difference between the driving signal of the Nth phase circuit and the driving signal of the N-1th phase circuit is 2π / N, the driving signal includes the inductor current signal and the inductor voltage signal, and N is an integer greater than 1.

7. A ZVS implementation method, applied to the PFC totem pole circuit according to any one of claims 1 to 6, comprising: Collecting the inductor current signal of the inductor by the current collection module; Collecting the inductor voltage signal of the inductor by the voltage collection module; The freewheeling tube is controlled according to the inductor current signal, and the main tube is controlled according to the inductor voltage signal.

8. The method according to claim 7, wherein the current acquisition module comprises a shunt and a first signal sampling circuit, the shunt is connected in series with the inductor, and the first signal sampling circuit is connected in parallel with the shunt; wherein, The collecting the inductor current signal of the inductor by the current collecting module includes: Collecting a first voltage across the shunt through the first signal sampling circuit; The first voltage is processed to obtain the inductor current signal.

9. The method according to claim 8, wherein the processing of the first voltage to obtain the inductor current signal comprises: Comparing the first voltage with a preset second voltage, and determining the inductor current signal according to the comparison result; or, determining a current signal flowing through the shunt according to the first voltage and the resistance value of the shunt; The current signal is determined as the inductor current signal.

10. The method according to claim 7, wherein the voltage acquisition module comprises an auxiliary winding and a second signal sampling circuit, the auxiliary winding is coupled with the inductor, and the second signal sampling circuit is connected in parallel with the auxiliary winding; The collecting of the inductor voltage signal of the inductor by the voltage collecting module includes: Collecting a third voltage and a fourth voltage at two ends of the auxiliary winding by the second signal sampling circuit; The third voltage is compared with the fourth voltage, and the inductor voltage signal is determined according to the comparison result.

11. The method according to claim 7, wherein the controlling the freewheeling tube according to the inductor current signal and the controlling the main tube according to the inductor voltage signal comprises: When the freewheeling tube is turned off, controlling the main tube to be turned on according to the inductor voltage signal; When the main tube is turned off, the freewheeling tube is turned on according to a preset dead time; When the freewheeling tube is turned on, the freewheeling tube is controlled to be turned off according to the inductor current signal.

12. The method according to claim 11, wherein, in the case where the main pipe is controlled to be turned on according to the inductor voltage signal, the method further comprises: determining the opening hours of said supervisor; When the switch-on time is reached, the main pipe is switched off.

13. The method of claim 12, wherein determining the activation time of the supervisor comprises: Determining the opening time of the main tube according to the circuit parameters of the PFC totem pole circuit; The circuit parameters include the input voltage, BUS voltage, At least one of an inductor and a phase-locked loop.

14. The method according to claim 11, wherein the inductor voltage signal comprises a high level signal, a low level signal, a rising edge signal and a falling edge signal; wherein, The controlling the main pipe to be opened according to the inductor voltage signal comprises: According to the high level signal and the low level signal, control the main tube to be opened; or, The main pipe is controlled to be opened according to the rising edge signal and the falling edge signal.

15. The method according to claim 11, wherein the inductor current signal comprises a high level signal, a low level signal, a rising edge signal and a falling edge signal, or the inductor current signal is a current signal; wherein, The controlling the freewheeling tube to turn off according to the inductor current signal comprises: Control the freewheeling tube to turn off according to the high level signal and the low level signal; or, Control the freewheeling tube to turn off according to the rising edge signal and the falling edge signal; or, When the current signal reaches a preset current value, the freewheeling tube is controlled to be turned off.

16. An electronic device, comprising: processor; a memory for storing instructions executable by the processor; The processor is configured to execute the instructions to implement the method according to any one of claims 7 to 15.

17. A computer-readable storage medium, when instructions in the storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the method according to any one of claims 7 to 15.

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