CN106787754A - Intelligent amendment wave voltage change-over circuit based on PFC interleaving inverse excitation full-bridges - Google Patents

Abstract

The invention discloses an intelligent modified wave voltage conversion circuit based on a PFC interleaved flyback full bridge, which includes: an input unit; a PFC boost unit; an interleaved flyback isolation conversion unit, which includes a first switch tube, a second Two switch tubes, a first transformer, a second transformer, a second rectifier diode and a third rectifier diode, the first end of the primary winding of the first transformer and the first end of the primary winding of the second transformer are both connected to the PFC step-up unit The output terminal of the first transformer primary winding is connected to the drain of the first switching tube, the second end of the primary winding of the second transformer is connected to the drain of the second switching tube, and the second The cathode of the rectifier diode is connected with the cathode of the third rectifier diode as the output end of the interleaved flyback isolation conversion unit; a DC filter unit; and an inverter and phase inverting unit. The invention can reduce ripple interference and improve output voltage quality.

Description

Intelligent Modified Wave Voltage Conversion Circuit Based on PFC Interleaved Flyback Full Bridge

technical field

The invention relates to a voltage conversion circuit, in particular to an intelligent modified wave voltage conversion circuit based on a PFC interleaved flyback full bridge.

Background technique

In the prior art, the intelligent buck-boost conversion device from AC to AC is also called a travel plug-in strip. In this device, the voltage conversion circuit is the key circuit, which is a circuit that can realize AC-AC conversion. In the AC-AC conversion, the function of realizing buck-boost and stabilizing voltage and frequency. However, most of the current AC-AC portable equipment market is a non-isolated topology circuit with low PF value, low output voltage quality, and poor safety and reliability. Especially in the voltage conversion process, more ripple interference will be generated, which will affect the voltage quality.

Contents of the invention

The technical problem to be solved by the present invention is to provide a safe and reliable PFC-based interleaved inverter that can reduce the ripple in the circuit, increase the PF value of the voltage conversion device, and improve the quality of the output voltage. An intelligent modified wave voltage conversion circuit that excites a full bridge.

In order to solve the above technical problems, the present invention adopts the following technical solutions.

An intelligent modified wave voltage conversion circuit based on PFC interleaved flyback full bridge, which includes: an input unit for providing DC voltage; a PFC boost unit connected to the output end of the input unit for input The output voltage of the unit is boosted and converted; an interleaved flyback isolation conversion unit includes a first switch tube, a second switch tube, a first transformer, a second transformer, a second rectifier diode and a third rectifier diode. Both the first end of the primary winding of a transformer and the first end of the primary winding of the second transformer are connected to the output end of the PFC step-up unit, and the second end of the primary winding of the first transformer is connected to the drain of the first switching tube, The second end of the primary winding of the second transformer is connected to the drain of the second switch tube, the source of the first switch tube and the source of the second switch tube are both connected to the front-end ground, and the first switch tube The grid of the second switching tube and the grid of the second switching tube are used to access two PWM pulse signals with opposite phases, the first end of the secondary winding of the first transformer is connected to the anode of the second rectifier diode, and the second transformer The first end of the secondary winding is connected to the anode of the third rectifier diode, the second end of the secondary winding of the first transformer and the second end of the secondary winding of the second transformer are both connected to the back-end ground, and the second The cathode of the rectifier diode is connected to the cathode of the third rectifier diode as the output end of the interleaved flyback isolation conversion unit; a DC filter unit includes a first electrolytic capacitor, and the anode of the first electrolytic capacitor is connected to the interleaved flyback The output terminal of the isolation conversion unit, the negative pole of the first electrolytic capacitor is connected to the back-end ground; an inverter inverter unit is connected to the output end of the interleaved flyback isolation conversion unit, and the inverter inverter unit is used for The output voltage of the interleaved flyback isolation transformation unit is inverted and converted to output alternating current.

Preferably, the interleaved flyback isolation conversion unit further includes a first freewheeling diode, a first resistor and a first capacitor, the anode of the first freewheeling diode is connected to the drain of the first switch transistor, and the first freewheeling diode A cathode of a freewheeling diode is connected to the output end of the PFC boost unit through a first resistor, and the first capacitor is connected in parallel with the first resistor.

Preferably, the interleaved flyback isolation conversion unit further includes a second freewheeling diode, a second resistor and a second capacitor, the anode of the second freewheeling diode is connected to the drain of the second switching tube, and the first The cathodes of the two freewheeling diodes are connected to the output terminal of the PFC step-up unit through a second resistor, and the second capacitor is connected in parallel with the second resistor.

Preferably, the input unit includes a socket, an insurance, a lightning protection resistor, a common-mode suppression inductor, a safety capacitor and a rectifier bridge. The front end is connected in parallel to the socket, the lightning protection resistor is connected in parallel to the front end of the common mode suppression inductor, the safety capacitor and the input end of the rectifier bridge are connected in parallel to the rear end of the common mode suppression inductor, and the output end of the rectifier bridge is connected in parallel with filter capacitor.

Preferably, the PFC boost unit includes a boost inductor, a third switch tube, a first rectifier diode and a second electrolytic capacitor, the front end of the boost inductor is connected to the output end of the input unit, and the boost inductor The rear end of the switch is connected to the drain of the third switch tube, the source of the third switch tube is connected to the front ground, the gate of the third switch tube is used to access a PWM control signal, and the third switch tube The drain of the first rectifier diode is connected to the anode of the first rectifier diode, the cathode of the first rectifier diode is used as the output end of the PFC boost unit, and the cathode of the first rectifier diode is connected to the positive pole of the second electrolytic capacitor, and the negative pole of the second electrolytic capacitor Connect to the front end.

Preferably, it also includes an MCU control unit, the grid of the first switch tube, the grid of the second switch tube and the grid of the third switch tube are respectively connected to the MCU control unit, and the MCU control unit is used for respectively Outputting PWM signals to the first switch tube, the second switch tube and the third switch tube to control the on-off states of the first switch tube, the second switch tube and the third switch tube.

Preferably, an AC sampling unit is also included, the AC sampling unit is connected between the input end of the input unit and the MCU control unit, and the AC sampling unit is used to collect the voltage on the AC side of the input unit and feed it back to the MCU control unit.

Preferably, a first sampling resistor is connected between the source of the third switching tube and the front-end ground, the source of the third switching tube is connected to the MCU control unit, and the MCU is controlled by the first sampling resistor. The control unit collects the electrical signal of the source of the third switch tube.

Preferably, it also includes a DC voltage sampling unit, the DC voltage sampling unit includes a second sampling resistor and a third sampling resistor connected in series in sequence, and the front end of the second sampling resistor is connected to the output of the interleaved flyback isolation conversion unit The rear end of the third sampling resistor is connected to the MCU control unit, and the MCU control unit collects the electrical signal output by the interleaved flyback isolation conversion unit through the second sampling resistor and the third sampling resistor.

Preferably, the inverter inverter unit includes an inverter bridge composed of a fourth switch tube, a fifth switch tube, a sixth switch tube and a seventh switch tube, the gate of the fourth switch tube, the fifth switch tube The grid of the tube, the grid of the sixth switch tube, and the grid of the seventh switch tube are respectively connected to the MCU control unit, and the fourth switch tube, the fifth switch tube, and the sixth switch tube are controlled by the MCU control unit. and the seventh switch tube are turned on or off, so that the inverter and inverter unit outputs an AC voltage.

In the intelligent modified wave voltage conversion circuit based on PFC interleaved flyback full bridge disclosed by the present invention, the PFC boost unit is used to boost the DC voltage output by the input unit, and then output to the interleaved flyback isolation conversion unit, wherein the first The first switch tube and the second switch tube are alternately conducted. When the first switch tube is turned on, the second switch tube is cut off, and the current forms a loop from the primary winding of the first transformer and the first switch tube to the front end. The primary transformer of the first transformer The winding starts to store energy; when the second switch tube is turned on, the first switch tube is turned off, and the current is formed by the primary winding of the second transformer, the second switch tube, and the front-end ground, and the primary winding of the second transformer starts to store energy, while the first transformer The electric energy of the primary winding is coupled to the secondary winding through its magnetic core, and then supplies power to the load through the second rectifier diode; then the first switching tube is turned on again, the second switching tube is turned off, the first transformer stores energy, and the second transformer The primary winding supplies power to the load through the third rectifier diode. In the above-mentioned interleaved flyback isolation conversion unit, due to the use of alternating conduction, the current ripple in the circuit is smaller and the application is more flexible. Especially when the load is small, only one flyback circuit needs to be started, and at the same time , the EMI and EMC interference of the above circuit are small, and the circuit operating frequency is high, which can improve the power density. In addition, the output voltage can be changed by changing the turns ratio of the first transformer and the second transformer, thereby realizing step-up or step-down.

Description of drawings

Fig. 1 is the circuit schematic diagram of the correction wave voltage conversion circuit.

Fig. 2 is a schematic circuit diagram of an AC sampling unit in a preferred embodiment of the present invention.

Fig. 3 is a schematic circuit diagram of the MCU control unit in the preferred embodiment of the present invention.

detailed description

The present invention will be described in more detail below in conjunction with the accompanying drawings and embodiments.

The invention discloses an intelligent modified wave voltage conversion circuit based on PFC interleaved flyback full bridge, which is shown in Fig. 1 to Fig. 3 , which includes:

An input unit 10, used to provide DC voltage;

A PFC step-up unit 20, connected to the output end of the input unit 10, for boosting the output voltage of the input unit 10;

An interleaved flyback isolation conversion unit 30, including a first switch tube Q6, a second switch tube Q7, a first transformer T1, a second transformer T2, a second rectifier diode D7 and a third rectifier diode D8, the first transformer Both the first end of the primary winding of T1 and the first end of the primary winding of the second transformer T2 are connected to the output end of the PFC step-up unit 20, and the second end of the primary winding of the first transformer T1 is connected to the first switching tube Q6. Drain, the second end of the primary winding of the second transformer T2 is connected to the drain of the second switching tube Q7, and the source of the first switching tube Q6 and the source of the second switching tube Q7 are both connected to the front-end ground , the gate of the first switching tube Q6 and the gate of the second switching tube Q7 are used to access two PWM pulse signals with opposite phases, and the first end of the secondary winding of the first transformer T1 is connected to the second The anode of the rectifier diode D7, the first end of the secondary winding of the second transformer T2 is connected to the anode of the third rectifying diode D8, the second end of the secondary winding of the first transformer T1 is connected to the secondary winding of the second transformer T2 The second end of each is connected to the back-end ground, and the cathode of the second rectifier diode D7 is connected to the cathode of the third rectifier diode D8 as the output end of the interleaved flyback isolation conversion unit 30;

A DC filtering unit 40, including a first electrolytic capacitor C3, the positive pole of the first electrolytic capacitor C3 is connected to the output end of the interleaved flyback isolation conversion unit 30, and the negative pole of the first electrolytic capacitor C3 is connected to the back-end ground ;

An inverter and phase conversion unit 60 is connected to the output end of the interleaved flyback isolation conversion unit 30 , and the inverter and phase conversion unit 60 is used to invert and convert the output voltage of the interleaved flyback isolation conversion unit 30 to output AC power.

In the above modified wave voltage conversion circuit, the DC voltage output by the input unit 10 is boosted by the PFC boost unit 20, and then output to the interleaved flyback isolation conversion unit 30, wherein the first switch tube Q6 and the second switch tube Q7 It is interleaved conduction, when the first switch tube Q6 is turned on, the second switch tube Q7 is turned off, the current is formed from the primary winding of the first transformer T1, the first switch tube Q6 to the front end, and the primary winding of the first transformer T1 starts to store ; When the second switch tube Q7 is turned on, the first switch tube Q6 is cut off, and the current is formed by the primary winding of the second transformer T2, the second switch tube Q7, and the front end ground, and the primary winding of the second transformer T2 starts to store energy. The electric energy of the primary winding of a transformer T1 is coupled to the secondary winding through its magnetic core, and then supplies power to the load through the second rectifier diode D7; then the first switching tube Q6 is turned on again, the second switching tube Q7 is turned off, and the first transformer T1 To store energy, the secondary winding of the second transformer T2 supplies power to the load through the third rectifier diode D8. In the above-mentioned interleaved flyback isolation conversion unit 30, due to the use of alternating conduction, the current ripple in the circuit is small and the application is relatively flexible. Especially when the load is small, only one flyback circuit needs to be started. At the same time, the EMI and EMC interference of the above circuit is small, and the circuit operating frequency is high, which can improve the power density. In addition, by changing the turns ratio of the first transformer T1 and the second transformer T2, the output voltage can be changed, thereby realizing step-up or step-down. pressure. In this embodiment, the first switch tube Q6 and the second switch tube Q7 modulate the high-frequency PWM signal at the power frequency, and make the first switch tube Q6 and the second switch tube Q7 adjust the output voltage according to the sinusoidal variation characteristic.

As a preferred manner, as shown in FIG. 1 , the interleaved flyback isolation conversion unit 30 also includes a first freewheeling diode D6, a first resistor R26 and a first capacitor C5, and the first freewheeling diode D6 The anode is connected to the drain of the first switch tube Q6, the cathode of the first freewheeling diode D6 is connected to the output terminal of the PFC boost unit 20 through the first resistor R26, and the first capacitor C5 is connected in parallel to the first resistor R26 . The interleaved flyback isolation conversion unit 30 also includes a second freewheeling diode D5, a second resistor R27 and a second capacitor C6, the anode of the second freewheeling diode D5 is connected to the drain of the second switching transistor Q7, The cathode of the second freewheeling diode D5 is connected to the output terminal of the PFC boost unit 20 through the second resistor R27, and the second capacitor C6 is connected in parallel to the second resistor R27.

In the above circuit, the second freewheeling diode D5, the first freewheeling diode D6, the first resistor R26, the second resistor R27, the first capacitor C5, and the second capacitor C6 are respectively the first switching tube Q6 and the second switching tube Q7. The suction circuit is used to absorb the peak voltage generated by the leakage inductance of the first transformer T1 and the second transformer T1, so as to reduce the voltage stress of the switch tube.

In the input part of this embodiment, the grid voltage is converted into a DC voltage for subsequent circuits. Specifically, the input unit 10 includes a socket, a fuse F2, a lightning protection resistor RV1, a common mode suppression inductor L1, and an Standard capacitor CX1 and rectifier bridge DB1, the insurance F2 is connected in series to the zero line or live line of the socket, the front end of the common mode suppression inductor L1 is connected in parallel to the socket, and the lightning protection resistor RV1 is connected in parallel to the common mode suppression inductor L1 At the front end, the safety capacitor CX1 and the input terminal of the rectifier bridge DB1 are connected in parallel to the rear end of the common mode suppression inductor L1, and the output terminal of the rectifier bridge DB1 is connected in parallel with a filter capacitor C1.

Regarding the boost part, the PFC boost unit 20 includes a boost inductor L2, a third switch tube Q5, a first rectifier diode D1 and a second electrolytic capacitor C2, and the front end of the boost inductor L2 is connected to the input unit 10 The output terminal of the boost inductor L2 is connected to the drain of the third switching tube Q5, the source of the third switching tube Q5 is connected to the front end, and the gate of the third switching tube Q5 is used for A PWM control signal is connected, the drain of the third switch tube Q5 is connected to the anode of the first rectifier diode D1, the cathode of the first rectifier diode D1 is used as the output end of the PFC boost unit 20, and the first rectifier The cathode of the diode D1 is connected to the positive pole of the second electrolytic capacitor C2, and the negative pole of the second electrolytic capacitor C2 is connected to the terminal ground.

The above-mentioned PFC boost unit 20, when sampling the half-wave AC voltage output by the filter capacitor C1, the PFC enters the boost mode to increase the PF value of the AC-to-AC intelligent step-down conversion topology circuit, and passes through the second electrolytic capacitor C2 after boosting. The filtered voltage is 400V. The specific boost principle is as follows: when the third switch tube Q5 is turned on, the current on the filter capacitor C1 forms a loop through the boost inductor L2 and the third switch tube Q5 to GND, and the boost inductor L2 stores Energy; when the third switching tube Q5 is turned off, an induced electromotive force much higher than the input voltage will be formed on the boost inductor, and the induced electromotive force will be rectified by the first rectifier diode D1 to form a one-way pulse voltage and then sent to the second electrolytic capacitor The C2 capacitor enters the filter, and the filter becomes a DC voltage of 400V. And the third switch tube Q5 increases or decreases the conduction time of the third switch tube Q5 according to the change of the input AC sine wave collected by the control chip, so that the phase of the current and the voltage become consistent to increase the PF value.

As a preferred mode, this embodiment also includes an MCU control unit 80, the gate of the first switch Q6, the gate of the second switch Q7 and the gate of the third switch Q5 are respectively connected to the MCU control unit 80. unit 80, the MCU control unit 80 is used to respectively output PWM signals to the first switch tube Q6, the second switch tube Q7 and the third switch tube Q5, so as to control the first switch tube Q6, the second switch tube Q7 and the third switch tube Q6 The on-off state of the switch tube Q5. Further, the MCU control unit 80 includes a single-chip microcomputer U1 and its peripheral circuits.

In order to facilitate the monitoring of the electrical signal on the AC side, as shown in Figure 2, an AC sampling unit 70 is also included, the AC sampling unit 70 is connected between the input end of the input unit 10 and the MCU control unit 80, the AC sampling unit 70 is used to collect the voltage of the AC side of the input unit 10 and feed it back to the MCU control unit 80 . Regarding the specific composition of the AC sampling unit 70, the AC sampling unit 70 includes an operational amplifier U9B, and the two input terminals of the operational amplifier U9B are respectively connected to the input terminals of the input unit 10 through a current limiting resistor. The output end of the amplifier U9B is connected to the MCU control unit 80 .

In order to facilitate real-time collection of current, a first sampling resistor R2A is connected between the source of the third switching tube Q5 and the front-end ground, and the source of the third switching tube Q5 is connected to the MCU control unit 80, by The first sampling resistor R2A enables the MCU control unit 80 to collect the electrical signal of the source of the third switching transistor Q5.

As a preferred manner, in order to collect the DC side electric signal, this embodiment also includes a DC voltage sampling unit 50, the DC voltage sampling unit 50 includes a second sampling resistor R13 and a third sampling resistor R15 connected in series in sequence , the front end of the second sampling resistor R13 is connected to the output end of the interleaved flyback isolation conversion unit 30, the rear end of the third sampling resistor R15 is connected to the MCU control unit 80, through the second sampling resistor R13 and The third sampling resistor R15 enables the MCU control unit 80 to collect the electrical signal output by the interleaved flyback isolation conversion unit 30 .

Regarding the inverter part, please refer to FIG. 3, the inverter and phase inverting unit 60 includes an inverter bridge composed of a fourth switching tube Q1, a fifth switching tube Q2, a sixth switching tube Q3 and a seventh switching tube Q4. The grid of the fourth switch Q1, the fifth switch Q2, the sixth switch Q3 and the seventh switch Q4 are respectively connected to the MCU control unit 80, controlled by the MCU The unit 80 controls the fourth switching tube Q1 , the fifth switching tube Q2 , the sixth switching tube Q3 and the seventh switching tube Q4 to be turned on or off, so that the inverter unit 60 outputs an AC voltage.

In the above inverter and phase inverting unit 60, the DC voltage filtered by the first electrolytic capacitor C3 forms a loop through the fourth switching tube Q1, the load, and the seventh switching tube Q4 to supply power to the load to form the first half-cycle power frequency level; The power frequency level of the second half cycle forms a loop through the fifth switching tube Q2, the load, and the sixth switching tube Q3, so that a complete power frequency correction wave AC voltage is formed on the load. The PWM signal output by the single-chip microcomputer U1 is sent to the GATE poles of the fourth switching tube Q1, the fifth switching tube Q2, the sixth switching tube Q3, and the seventh switching tube Q4 respectively through the driving circuit and then sending PWM1H, PWM1L, PWM2H, and PWM2L. The phase and frequency in the inverter inverter circuit work according to the mode set inside the control chip.

The intelligent modified wave voltage conversion circuit based on the PFC interleaved flyback full bridge disclosed by the present invention has a high PF value, isolation from the power grid and the output end, and very high safety compared with the prior art, and the DC and DC units adopt interactive The working mode EMC, EMI interference is small, and the power application is flexible. The output voltage can be automatically adjusted within the full input voltage range, and the output frequency is fixed, and the output voltage is output with a modified wave, which has an automatic shaping function for the AC voltage. In addition, the invention contains a voltage and current sampling circuit, which can effectively prevent waves surge voltage and current.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. All modifications, equivalent replacements or improvements made within the technical scope of the present invention shall be included in the protection scope of the present invention.

Claims (10)

1. a kind of intelligent amendment wave voltage change-over circuit based on PFC interleaving inverse excitation full-bridges, it is characterised in that include：

One input block (10), for providing DC voltage；

One PFC boost unit (20), is connected to the output end of input block (10), for the output voltage to input block (10) Carry out boost conversion；

One interleaving inverse excitation isolated variable unit (30), includes first switch pipe (Q6), second switch pipe (Q7), the first transformer (T1), the second transformer (T2), the second commutation diode (D7) and the 3rd commutation diode (D8), first transformer (T1) The first end of the first end of armature winding and the second transformer (T2) armature winding is all connected to the output of PFC boost unit (20) End, the second end of the first transformer (T1) armature winding is connected to the drain electrode of first switch pipe (Q6), second transformation Second end of device (T2) armature winding is connected to the drain electrode of second switch pipe (Q7), the source electrode of the first switch pipe (Q6) and The source electrode of two switching tubes (Q7) is all connected to front end ground, the grid of the first switch pipe (Q6) and the grid of second switch pipe (Q7) Pole is used to access the pwm pulse signal of two-way opposite in phase, and the first end of the first transformer (T1) secondary windings is connected to The anode of the second commutation diode (D7), the first end of the second transformer (T2) secondary windings is connected to the pole of the 3rd rectification two Manage the anode of (D8), the second end of the first transformer (T1) secondary windings and the second of the second transformer (T2) secondary windings End is all connected to rear end ground, and the negative electrode of second commutation diode (D7) and the negative electrode of the 3rd commutation diode (D8) are connected Afterwards as the output end of interleaving inverse excitation isolated variable unit (30)；

One DC filter units (40), include the first electrochemical capacitor (C3), and the positive pole of first electrochemical capacitor (C3) is connected to The output end of interleaving inverse excitation isolated variable unit (30), the negative pole of first electrochemical capacitor (C3) is connected to rear end ground；

One inversion reversed phase unit (60), is connected to the output end of interleaving inverse excitation isolated variable unit (30), the inversion paraphase list First (60) export alternating current after carrying out inversion conversion for the output voltage to interleaving inverse excitation isolated variable unit (30).

2. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges is based on as claimed in claim 1, and its feature exists In the interleaving inverse excitation isolated variable unit (30) also includes the first fly-wheel diode (D6), first resistor (R26) and first Electric capacity (C5), the anode of first fly-wheel diode (D6) is connected to the drain electrode of first switch pipe (Q6), first afterflow The negative electrode of diode (D6) is connected to the output end of PFC boost unit (20), first electric capacity by first resistor (R26) (C5) it is parallel to first resistor (R26).

3. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges is based on as claimed in claim 1, and its feature exists In the interleaving inverse excitation isolated variable unit (30) also includes the second fly-wheel diode (D5), second resistance (R27) and second Electric capacity (C6), the anode of second fly-wheel diode (D5) is connected to the drain electrode of second switch pipe (Q7), second afterflow The negative electrode of diode (D5) is connected to the output end of PFC boost unit (20), second electric capacity by second resistance (R27) (C6) it is parallel to second resistance (R27).

4. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges is based on as claimed in claim 1, and its feature exists In the input block (10) includes socket, insurance (F2), lightning protection resistance (RV1), common mode inhibition inductance (L1), safety electricity Hold (CX1) and rectifier bridge (DB1), the insurance (F2) is serially connected with the zero line of socket or live wire, the common mode inhibition inductance (L1) front end is parallel to socket, and the lightning protection resistance (RV1) is parallel to the front end of common mode inhibition inductance (L1), the safety electricity The input of appearance (CX1) and rectifier bridge (DB1) is parallel to the rear end of common mode inhibition inductance (L1), the rectifier bridge (DB1) Output end is parallel with filter capacitor (C1).

5. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges is based on as claimed in claim 1, and its feature exists In, the PFC boost unit (20) include boost inductance (L2), the 3rd switching tube (Q5), the first commutation diode (D1) and Second electrochemical capacitor (C2), the front end of the boost inductance (L2) is connected to the output end of input block (10), described liter of piezoelectricity The rear end for feeling (L2) is connected to the drain electrode of the 3rd switching tube (Q5), and the source electrode of the 3rd switching tube (Q5) connects front end ground, described The grid of the 3rd switching tube (Q5) is used to access pwm control signal all the way, the drain electrode connection first of the 3rd switching tube (Q5) The anode of commutation diode (D1), the negative electrode of first commutation diode (D1) as PFC boost unit (20) output end, And the negative electrode of first commutation diode (D1) connects the positive pole of the second electrochemical capacitor (C2), the negative pole of the second electrochemical capacitor (C2) Connect front end ground.

6. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges is based on as claimed in claim 5, and its feature exists In, also include a MCU control unit (80), the grid of the first switch pipe (Q6), the grid of second switch pipe (Q7) and The grid of the 3rd switching tube (Q5) is connected to MCU control unit (80), and the MCU control unit (80) for exporting respectively Pwm signal to first switch pipe (Q6), second switch pipe (Q7) and the 3rd switching tube (Q5), with control first switch pipe (Q6), Second switch pipe (Q7) and the 3rd switching tube (Q5) on off operating mode.

7. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges is based on as claimed in claim 6, and its feature exists In, an AC sampling unit (70) is also included, the AC sampling unit (70) is connected to the input of input block (10) Between MCU control unit (80), the AC sampling unit (70) for gather input block (10) AC voltage simultaneously Feed back to MCU control unit (80).

8. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges is based on as claimed in claim 6, and its feature exists In being connected with the first sampling resistor (R2A), the 3rd switching tube between the source electrode and front end ground of the 3rd switching tube (Q5) (Q5) source electrode is connected to MCU control unit (80), and MCU control unit (80) is made by first sampling resistor (R2A) Gather the electric signal of the 3rd switching tube (Q5) source electrode.

9. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges is based on as claimed in claim 6, and its feature exists In, a D/C voltage sampling unit (50) is also included, the D/C voltage sampling unit (50) includes second for being sequentially connected in series and adopts Sample resistance (R13) and the 3rd sampling resistor (R15), the front end of second sampling resistor (R13) are connected to interleaving inverse excitation isolation The output end of converter unit (30), the rear end of the 3rd sampling resistor (R15) is connected to MCU control unit (80), by institute State the second sampling resistor (R13) and the 3rd sampling resistor (R15) and make MCU control unit (80) gather interleaving inverse excitation isolated variable The electric signal of unit (30) output.

10. the intelligent amendment wave voltage change-over circuit of PFC interleaving inverse excitation full-bridges, its feature are based on as claimed in claim 6 Be, the inversion reversed phase unit (60) including by the 4th switching tube (Q1), the 5th switching tube (Q2), the 6th switching tube (Q3) and The inverter bridge of the 7th switching tube (Q4) composition, the grid of the 4th switching tube (Q1), grid, the 6th of the 5th switching tube (Q2) The grid of the grid of switching tube (Q3) and the 7th switching tube (Q4) is connected to MCU control unit (80), is controlled by the MCU Unit (80) processed and control the 4th switching tube (Q1), the 5th switching tube (Q2), the 6th switching tube (Q3) and the 7th switching tube (Q4) On or off, to make inversion reversed phase unit (60) output AC voltage.