CN115549447A

CN115549447A - Auxiliary power supply circuit suitable for driver

Info

Publication number: CN115549447A
Application number: CN202211526925.0A
Authority: CN
Inventors: 龚耀京; 杨运海; 张荣亮; 马蕾
Original assignee: Shenzhen Farwide Electric Co ltd
Current assignee: Shenzhen Farwide Electric Co ltd
Priority date: 2022-12-01
Filing date: 2022-12-01
Publication date: 2022-12-30
Anticipated expiration: 2042-12-01
Also published as: CN115549447B

Abstract

The invention discloses an auxiliary power supply circuit suitable for a driver, which comprises: the flyback control circuit and the multi-channel flyback output transformer; the multi-path flyback output transformer comprises a primary side first winding, a primary side second winding, a primary side output circuit, a secondary side winding set and a secondary side output circuit set; the primary side output circuit is connected with the primary side second winding, the secondary side winding set comprises at least one secondary side winding, the secondary side output circuit set comprises at least one secondary side output circuit, and the at least one secondary side output circuit is correspondingly connected with the at least one secondary side winding respectively; one end of the primary side first winding is coupled with the low-voltage power supply, and the other end of the primary side first winding is coupled with the flyback control circuit, so that the multi-path flyback output transformer outputs at least two auxiliary power supplies through the primary side output circuit and the secondary side output circuit. The invention can provide an auxiliary power supply with low voltage power supply, can avoid the problem of misoperation failure caused by high voltage power supply on the driver, and can reduce the production cost.

Description

Auxiliary power supply circuit suitable for driver

Technical Field

The invention relates to the technical field of drivers, in particular to an auxiliary power supply circuit suitable for a driver.

Background

At present, with the continuous progress of electronic technology, drivers (mainly including electric devices which are conventionally called frequency converters, servo drivers, inverters, motor speed regulators and the like in the market and adopt power electronic technology) are widely applied. In the application of the driver, when the driver is directly supplied with high voltage, the problem of misoperation failure can exist, and moreover, when the driver is supplied with high voltage, a high-voltage device is required to be used, so that the production cost is increased.

Disclosure of Invention

In order to solve the technical problems, the invention provides an auxiliary power supply circuit suitable for a driver, which can provide an auxiliary power supply with low-voltage power supply, can avoid the problem of misoperation failure caused by high-voltage power supply on the driver, and can reduce the production cost.

The invention provides an auxiliary power supply circuit suitable for a driver, which comprises: the flyback control circuit and the multi-path flyback output transformer; the multi-path flyback output transformer comprises a primary side first winding, a primary side second winding, a primary side output circuit, a secondary side winding set and a secondary side output circuit set; the primary side output circuit is connected with the primary side second winding, the secondary side winding set comprises at least one secondary side winding, the at least one secondary side winding is coupled with the primary side first winding and the primary side second winding, the secondary side output circuit set comprises at least one secondary side output circuit, and the at least one secondary side output circuit and the at least one secondary side winding are respectively and correspondingly connected.

One end of the primary side first winding is coupled with a low-voltage power supply, and the other end of the primary side first winding is coupled with the flyback control circuit, so that the multi-path flyback output transformer outputs at least two auxiliary power supplies through the primary side output circuit and the secondary side output circuit set.

Furthermore, any one of the at least two auxiliary power supplies is connected with a forward control circuit, and the forward control circuit is connected with a forward transformer set; the forward transformer set comprises at least one forward transformer, and the forward transformer is used for outputting an IGBT driving power supply.

Further, the primary side output circuit comprises a first diode, a second diode, a first electrolytic capacitor and a first capacitor.

The positive electrode of the first diode and the positive electrode of the second diode are connected with the dotted terminal of the primary side second winding, the negative electrode of the first diode and the negative electrode of the second diode are connected with the positive electrode of the first electrolytic capacitor and the first terminal of the first capacitor, and the negative electrode of the first electrolytic capacitor, the second terminal of the first capacitor and the dotted terminal of the primary side second winding are grounded.

And the node connected with the cathode of the first diode, the cathode of the second diode, the anode of the first electrolytic capacitor and the first end of the first capacitor is used as the output end of the primary side output circuit to output a first auxiliary power supply.

Further, the at least one secondary side output circuit comprises a first secondary side output circuit, and the first secondary side output circuit comprises a third diode, a fourth diode, a second electrolytic capacitor, a third electrolytic capacitor, a second capacitor, a third capacitor and a first resistor.

The positive pole of the third diode is connected with the homonymous end of the corresponding first secondary winding, the negative pole of the third diode is connected with the positive pole of the second electrolytic capacitor and the first end of the second capacitor, the negative pole of the second electrolytic capacitor, the second end of the second capacitor, the positive pole of the third electrolytic capacitor, the first end of the third capacitor and the first end of the first resistor are connected with the corresponding heteronymous end of the first secondary winding, the negative pole of the third electrolytic capacitor, the second end of the third capacitor and the second end of the first resistor are connected with the positive pole of the fourth diode, and the negative pole of the fourth diode is connected with the heteronymous end of the corresponding second secondary winding.

A node connecting the cathode of the third diode, the anode of the second electrolytic capacitor and the first end of the second capacitor is used as a first output end of the first secondary side output circuit to output a second auxiliary power supply; and a node connected with the anode of the fourth diode, the cathode of the third electrolytic capacitor, the second end of the third capacitor and the second end of the first resistor is used as a second output end of the first secondary side output circuit to output a third auxiliary power supply.

Further, the at least one secondary side output circuit further comprises a second secondary side output circuit comprising a fifth diode, a first inductor, a fourth electrolytic capacitor, and a fourth capacitor.

The negative electrode of the fifth diode is connected with the synonym end of the corresponding secondary winding, the positive electrode of the fifth diode is connected with the first end of the first inductor, the second end of the first inductor is connected with the negative electrode of the fourth electrolytic capacitor and the second end of the fourth capacitor, and the corresponding synonym end of the secondary winding, the positive electrode of the fourth electrolytic capacitor and the first end of the fourth capacitor are grounded.

And a node which is connected with the second end of the first inductor, the cathode of the fourth electrolytic capacitor and the second end of the fourth capacitor is used as an output end of the second secondary side output circuit to output a fourth auxiliary power supply.

Further, the at least one secondary side output circuit further comprises a third secondary side output circuit, and the third secondary side output circuit comprises a sixth diode, a fifth electrolytic capacitor, a fifth capacitor and a second resistor.

The positive pole of the sixth diode is connected with one end of the corresponding secondary winding, the negative pole of the sixth diode is connected with the positive pole of the fifth electrolytic capacitor, the first end of the fifth capacitor and the first end of the second resistor, and the negative pole of the fifth electrolytic capacitor, the second end of the fifth capacitor and the second end of the second resistor are connected with the other end of the corresponding secondary winding.

And a node connected with the cathode of the sixth diode, the anode of the fifth electrolytic capacitor, the first end of the fifth capacitor and the first end of the second resistor is used as an output end of the third secondary side output circuit to output a fifth auxiliary power supply.

Further, the forward control circuit includes a timer chip, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, a thirteenth capacitor, a sixth electrolytic capacitor, a seventh electrolytic capacitor, an eighth electrolytic capacitor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a first field effect transistor, and a second field effect transistor.

A first end of the sixth capacitor, an anode of the sixth electrolytic capacitor, a first end of the third resistor, a VCC pin of the timer chip, and a RESET pin of the timer chip are connected to the first auxiliary power supply, a second end of the third resistor is connected to a first end of the fourth resistor, a second end of the fourth resistor is connected to a first end of the fifth resistor, a second end of the fifth resistor is connected to a first end of the seventh capacitor, a THOLD pin of the timer chip, a TRIG pin of the timer chip, and a first end of the sixth resistor, a second end of the seventh capacitor is grounded to a GND pin of the timer chip, an OUT pin of the timer chip is connected to a second end of the sixth resistor, a first end of the seventh resistor, and a first end of the tenth resistor, a second end of the seventh resistor is connected to a first end of the eighth capacitor, a second end of the eighth capacitor is connected with a second end of the eighth resistor and the gate of the first field effect transistor, a second end of the tenth resistor is connected with a first end of the ninth capacitor, a second end of the ninth capacitor is connected with a first end of the eleventh resistor and the gate of the second field effect transistor, a drain of the second field effect transistor is connected with a drain of the first field effect transistor, a source of the first field effect transistor, a first end of the eighth resistor, an anode of the seventh electrolytic capacitor, a first end of the twelfth capacitor and a first end of the ninth resistor are connected with the first auxiliary power supply, a cathode of the seventh electrolytic capacitor is connected with a second end of the tenth capacitor, a second end of the eleventh capacitor, an anode of the eighth electrolytic capacitor, a second end of the twelfth capacitor, a drain of the twelfth capacitor, the second end of the ninth resistor, the first end of the thirteenth capacitor and the first end of the twelfth resistor are connected, the first end of the tenth capacitor and the first end of the eleventh capacitor are connected, and the second end of the eleventh resistor, the source electrode of the second field effect transistor, the cathode of the eighth electrolytic capacitor, the second end of the thirteenth capacitor and the second end of the twelfth resistor are grounded.

And a node connecting the drain electrode of the second field effect transistor and the drain electrode of the first field effect transistor is used as a first output end of the forward control circuit, and a node connecting the first end of the tenth capacitor and the first end of the eleventh capacitor is used as a second output end of the forward control circuit.

Further, the forward transformer set comprises a first forward transformer, and the first forward transformer comprises a primary input first winding, a primary first winding, a secondary second winding, a first W-phase upper bridge driving power circuit, a first U-phase upper bridge driving power circuit, and a first V-phase upper bridge driving power circuit.

The homonymous end of the primary side input first winding is connected with the first output end of the forward control circuit, and the heteronymous end of the primary side input first winding is connected with the second output end of the forward control circuit.

The first W-phase upper bridge driving power supply circuit comprises a ninth electrolytic capacitor, a tenth electrolytic capacitor, a seventh diode, an eighth diode, a ninth diode and a fourteenth capacitor, wherein a second end of the fourteenth capacitor and a cathode of the ninth diode are connected with the dotted end of the primary first winding, a first end of the fourteenth capacitor is connected with an anode of the seventh diode and a cathode of the eighth diode, a cathode of the seventh diode is connected with an anode of the ninth electrolytic capacitor, an anode of the eighth diode is connected with a cathode of the ninth electrolytic capacitor, an anode of the tenth electrolytic capacitor and a dotted end of the primary first winding, and a cathode of the tenth electrolytic capacitor is connected with an anode of the ninth diode.

The first U-phase upper bridge driving power supply circuit comprises a fifteenth capacitor, a twelfth diode, an eleventh diode, a twelfth diode, an eleventh electrolytic capacitor and a twelfth electrolytic capacitor; the first end of the fifteenth capacitor and the cathode of the twelfth diode are connected with the dotted terminal of the secondary first winding, the second end of the fifteenth capacitor is connected with the cathode of the twelfth diode and the anode of the eleventh diode, the anode of the twelfth diode, the cathode of the eleventh electrolytic capacitor and the anode of the twelfth electrolytic capacitor are connected with the dotted terminal of the secondary first winding, the cathode of the eleventh diode is connected with the anode of the eleventh electrolytic capacitor, and the anode of the twelfth diode is connected with the cathode of the twelfth electrolytic capacitor.

The first V-phase upper bridge driving power supply circuit comprises a sixteenth capacitor, a thirteenth diode, a fourteenth diode, a fifteenth diode, a thirteenth electrolytic capacitor and a fourteenth electrolytic capacitor; a first end of the sixteenth capacitor and a cathode of the fifteenth diode are connected with a dotted terminal of the secondary winding, a second end of the sixteenth capacitor is connected with a cathode of the thirteenth diode and an anode of the fourteenth diode, an anode of the thirteenth diode, a cathode of the thirteenth electrolytic capacitor and an anode of the fourteenth electrolytic capacitor are connected with a dotted terminal of the secondary winding, a cathode of the fourteenth diode is connected with an anode of the thirteenth electrolytic capacitor, and an anode of the fifteenth diode is connected with a cathode of the fourteenth electrolytic capacitor.

Further, the forward transformer set further includes a second forward transformer, and the second forward transformer includes a primary input second winding, a primary second winding, a secondary third winding, a secondary fourth winding, a second W-phase upper bridge driving power supply circuit, a second U-phase upper bridge driving power supply circuit, and a second V-phase upper bridge driving power supply circuit.

The homonymous end of the primary side input second winding is connected with the first output end of the forward control circuit, and the heteronymous end of the primary side input second winding is connected with the second output end of the forward control circuit.

The second W-phase upper bridge driving power circuit comprises a fifteenth electrolytic capacitor, a sixteenth diode, a seventeenth diode, an eighteenth diode and a seventeenth capacitor, wherein a second end of the seventeenth capacitor and a cathode of the eighteenth diode are connected with the same-name end of the primary second winding, a first end of the seventeenth capacitor is connected with an anode of the sixteenth diode and a cathode of the seventeenth diode, a cathode of the sixteenth diode is connected with an anode of the fifteenth electrolytic capacitor, an anode of the seventeenth diode is connected with a cathode of the fifteenth electrolytic capacitor, an anode of the sixteenth electrolytic capacitor and a different-name end of the primary second winding, and a cathode of the sixteenth electrolytic capacitor is connected with an anode of the eighteenth diode.

The second U-phase upper bridge driving power supply circuit comprises an eighteenth capacitor, a nineteenth diode, a twentieth diode, a twenty-first diode, a seventeenth electrolytic capacitor and an eighteenth electrolytic capacitor; the first end of eighteenth electric capacity with the negative pole of twenty-first diode with the end connection of the same name of secondary third winding, the second end of eighteenth electric capacity with the negative pole of nineteenth diode with the positive pole of twentieth diode is connected, the positive pole of nineteenth diode the negative pole of seventeenth electrolytic capacitor with the positive pole of eighteenth electrolytic capacitor with the end connection of different name of secondary third winding, the negative pole of twentieth diode with the positive pole of seventeenth electrolytic capacitor is connected, the positive pole of twenty-first diode with the negative pole of eighteenth electrolytic capacitor is connected.

The second V-phase upper bridge driving power supply circuit comprises a nineteenth capacitor, a twenty-second diode, a twenty-third diode, a twenty-fourth diode, a nineteenth electrolytic capacitor and a twentieth electrolytic capacitor; the first end of the nineteenth capacitor and the cathode of the twenty-fourth diode are connected with the dotted terminal of the secondary fourth winding, the second end of the nineteenth capacitor is connected with the cathode of the twenty-second diode and the anode of the twenty-third diode, the anode of the twenty-second diode, the cathode of the nineteenth electrolytic capacitor and the anode of the twentieth electrolytic capacitor are connected with the dotted terminal of the secondary fourth winding, the cathode of the twenty-third diode is connected with the anode of the nineteenth electrolytic capacitor, and the anode of the twenty-fourth diode is connected with the cathode of the twentieth electrolytic capacitor.

Further, the forward transformer set further comprises a third forward transformer and a fourth forward transformer.

The third forward transformer comprises a primary input third winding, a primary third winding, a secondary fifth winding, a secondary sixth winding, a third W-phase upper bridge driving power circuit, a third U-phase upper bridge driving power circuit and a third V-phase upper bridge driving power circuit.

The homonymous end of the primary-side input third winding is connected with the first output end of the forward control circuit, and the heteronymous end of the primary-side input third winding is connected with the second output end of the forward control circuit.

The third W-phase upper bridge driving power circuit comprises a twenty-first electrolytic capacitor, a twenty-second electrolytic capacitor, a twenty-fifth diode, a twenty-sixth diode, a twenty-seventh diode and a twentieth capacitor, wherein a second end of the twentieth capacitor and a cathode of the twenty-seventh diode are connected with the same-name end of the primary third winding, a first end of the twentieth capacitor is connected with an anode of the twenty-fifth diode and a cathode of the twenty-sixth diode, a cathode of the twenty-fifth diode is connected with an anode of the twenty-first electrolytic capacitor, an anode of the twenty-sixth diode is connected with a cathode of the twenty-first electrolytic capacitor, an anode of the twenty-second electrolytic capacitor and a different-name end of the primary third winding, and a cathode of the twenty-second electrolytic capacitor is connected with an anode of the twenty-seventh diode.

The third U-phase upper bridge driving power supply circuit comprises a twenty-first capacitor, a twenty-eighth diode, a twenty-ninth diode, a thirty-third diode, a twenty-third electrolytic capacitor and a twenty-fourth electrolytic capacitor; the first end of the twenty-first capacitor and the cathode of the thirty-third diode are connected with the dotted terminal of the secondary fifth winding, the second end of the twenty-first capacitor is connected with the cathode of the twenty-eighth diode and the anode of the twenty-ninth diode, the anode of the twenty-eighth diode, the cathode of the twenty-third electrolytic capacitor and the anode of the twenty-fourth electrolytic capacitor are connected with the dotted terminal of the secondary fifth winding, the cathode of the twenty-ninth diode is connected with the anode of the twenty-third electrolytic capacitor, and the anode of the thirty-fourth diode is connected with the cathode of the twenty-fourth electrolytic capacitor.

The third V-phase upper bridge driving power supply circuit comprises a twenty-second capacitor, a thirty-first diode, a thirty-second diode, a thirty-third diode, a twenty-fifth electrolytic capacitor and a twenty-sixth electrolytic capacitor; the first end of the twenty-second capacitor and the cathode of the thirty-third diode are connected with the dotted terminal of the secondary sixth winding, the second end of the twenty-second capacitor is connected with the cathode of the thirty-first diode and the anode of the thirty-second diode, the anode of the thirty-first diode, the cathode of the twenty-fifth electrolytic capacitor and the anode of the twenty-sixth electrolytic capacitor are connected with the dotted terminal of the secondary sixth winding, the cathode of the thirty-second diode is connected with the anode of the twenty-fifth electrolytic capacitor, and the anode of the thirty-third diode is connected with the cathode of the twenty-sixth electrolytic capacitor.

The fourth forward transformer comprises a primary input fourth winding, a primary fourth winding, a secondary seventh winding, a secondary eighth winding, a fourth W-phase upper bridge driving power circuit, a fourth U-phase upper bridge driving power circuit and a fourth V-phase upper bridge driving power circuit.

The homonymous terminal of the primary side input fourth winding is connected with the first output terminal of the forward control circuit, and the heteronymous terminal of the primary side input fourth winding is connected with the second output terminal of the forward control circuit.

The fourth W-phase upper bridge driving power supply circuit comprises a twenty-seventh electrolytic capacitor, a twenty-eighth electrolytic capacitor, a thirty-fourth diode, a thirty-fifth diode, a thirty-sixth diode and a twenty-third capacitor, wherein a second end of the twenty-third capacitor and a cathode of the thirty-sixth diode are connected with a same-name end of the primary fourth winding, a first end of the twenty-third capacitor is connected with an anode of the thirty-fourth diode and a cathode of the thirty-fifth diode, a cathode of the thirty-fourth diode is connected with an anode of the twenty-seventh electrolytic capacitor, an anode of the thirty-fifth diode is connected with a cathode of the twenty-seventh electrolytic capacitor, an anode of the twenty-eighth electrolytic capacitor and a different-name end of the primary fourth winding, and a cathode of the twenty-eighth electrolytic capacitor is connected with an anode of the thirty-sixth diode.

The fourth U-phase upper bridge driving power supply circuit comprises a twenty-fourth capacitor, a thirty-seventh diode, a thirty-eighth diode, a thirty-ninth diode, a twenty-ninth electrolytic capacitor and a thirty-ninth electrolytic capacitor; the first end of the twenty-fourth capacitor and the cathode of the thirty-ninth diode are connected with the dotted terminal of the secondary seventh winding, the second end of the twenty-fourth capacitor is connected with the cathode of the thirty-seventh diode and the anode of the thirty-eighth diode, the anode of the thirty-seventh diode, the cathode of the twenty-ninth electrolytic capacitor and the anode of the thirty-eighth electrolytic capacitor are connected with the dotted terminal of the secondary seventh winding, the cathode of the thirty-eighth diode is connected with the anode of the twenty-ninth electrolytic capacitor, and the anode of the thirty-ninth diode is connected with the cathode of the thirty-ninth electrolytic capacitor.

The fourth V-phase upper bridge driving power supply circuit comprises a twenty-fifth capacitor, a forty-fifth diode, a forty-second diode, a thirty-first electrolytic capacitor and a thirty-second electrolytic capacitor; the first end of the twenty-fifth capacitor and the cathode of the forty-second diode are connected with the dotted terminal of the secondary eighth winding, the second end of the twenty-fifth capacitor is connected with the cathode of the forty-second diode and the anode of the forty-second diode, the cathode of the thirty-first electrolytic capacitor and the anode of the thirty-second electrolytic capacitor are connected with the dotted terminal of the secondary eighth winding, the cathode of the forty-second diode is connected with the anode of the thirty-first electrolytic capacitor, and the anode of the forty-second diode is connected with the cathode of the thirty-second electrolytic capacitor.

Compared with the prior art, the invention discloses an auxiliary power supply circuit suitable for a driver, which comprises: the flyback control circuit and the multi-channel flyback output transformer; the multi-path flyback output transformer comprises a primary side first winding, a primary side second winding, a primary side output circuit, a secondary side winding set and a secondary side output circuit set; the primary side output circuit is connected with the primary side second winding, the secondary side winding set comprises at least one secondary side winding, the secondary side output circuit set comprises at least one secondary side output circuit, and the at least one secondary side output circuit is correspondingly connected with the at least one secondary side winding respectively; one end of the primary side first winding is coupled with the low-voltage power supply, and the other end of the primary side first winding is coupled with the flyback control circuit, so that the multi-path flyback output transformer outputs at least two auxiliary power supplies through the primary side output circuit and the secondary side output circuit. The invention can provide an auxiliary power supply with low voltage power supply, can avoid the problem of misoperation failure caused by high voltage power supply on the driver, and can reduce the production cost.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the description below are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an auxiliary power supply circuit for a driver according to an embodiment of the present invention;

fig. 2 is a circuit diagram of an auxiliary power circuit for a driver according to an embodiment of the present invention;

FIG. 3 is a circuit diagram of a forward control circuit according to an embodiment of the present invention;

fig. 4 is a circuit diagram of a first forward transformer, a second forward transformer, a third forward transformer and a fourth forward transformer according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the specification of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be further understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

In any one of the resistors or capacitors mentioned in the embodiments of the present invention, if the resistor or capacitor is horizontally arranged in a circuit diagram, the resistor or capacitor is a first end of the resistor, capacitor or inductor and a second end of the resistor or capacitor from left to right in sequence; if the resistor, the capacitor or the inductor is arranged in the circuit diagram perpendicular to the horizontal direction, the first end of the resistor, the capacitor or the inductor and the second end of the resistor, the capacitor or the inductor are arranged from top to bottom in sequence.

Referring to fig. 1 to 4, fig. 1 is a schematic structural diagram of an auxiliary power circuit for a driver according to an embodiment of the present invention; fig. 2 is a circuit diagram of an auxiliary power circuit for a driver according to an embodiment of the present invention; FIG. 3 is a circuit diagram of a forward control circuit according to an embodiment of the present invention; fig. 4 is a circuit diagram of a first forward transformer, a second forward transformer, a third forward transformer and a fourth forward transformer according to an embodiment of the present invention. The auxiliary power supply circuit suitable for the driver is applied to the driver and provides different auxiliary power supplies for the driver.

The invention provides an auxiliary power supply circuit suitable for a driver, which comprises: the flyback control circuit 1 and the multi-path flyback output transformer T1; the multi-path flyback output transformer T1 comprises a primary side first winding N1, a primary side second winding N2, a primary side output circuit V1, a secondary side winding set Nx and a secondary side output circuit set Vx; the primary side output circuit V1 is connected with the primary side second winding N2, the secondary side winding set Nx comprises at least one secondary side winding, the at least one secondary side winding is coupled with the primary side first winding N1 and the primary side second winding N2, the secondary side output circuit set Vx comprises at least one secondary side output circuit, and the at least one secondary side output circuit is correspondingly connected with the at least one secondary side winding respectively; one end of the primary side first winding N1 is coupled with a low-voltage power supply, and the other end of the primary side first winding N1 is coupled with the flyback control circuit 1, so that the multi-path flyback output transformer T1 outputs at least two auxiliary power supplies through the primary side output circuit V1 and the secondary side output circuit set Vx.

In the present embodiment, referring to fig. 1 and fig. 2, the multiple flyback output transformer T1 is powered by a low voltage power supply, which may preferably be a 24V power supply. The primary side first winding N1 of the multi-path flyback output transformer T1 is coupled with the low-voltage power supply and the flyback control circuit 1, and a primary side feedback mode is adopted, so that the multi-path flyback output transformer T1 can output at least two auxiliary power supplies through the primary side output circuit V1 and the secondary side output circuit set Vx. The flyback control circuit 1 can provide a voltage stabilizing function, and the multi-channel flyback output transformer T1 can stably output the auxiliary power supply through the flyback control circuit 1. In addition, an auxiliary power supply can be generated by connecting the primary secondary winding N2 in the multi-path flyback output transformer T1 with the primary output circuit V1, at least one auxiliary power supply can be generated by at least one auxiliary winding and the correspondingly connected auxiliary output circuit, and the generated auxiliary power supply can supply power to the flyback control circuit 1 and can also supply power to other devices in the circuit. The invention can provide an auxiliary power supply with low voltage power supply, can avoid the problem of misoperation failure caused by high voltage power supply on the driver, and can save the high voltage device used in the original high voltage power supply by low voltage power supply, thereby reducing the production cost and the volume and being beneficial to fault maintenance.

In a more specific embodiment, any one of the at least two auxiliary power supplies is connected to a forward control circuit 2, and the forward control circuit 2 is connected to a forward transformer set Tx; the forward transformer set Tx comprises at least one forward transformer, and the forward transformer is used for outputting an IGBT driving power supply.

In the present embodiment, referring to fig. 1 to 4, one of the multiple auxiliary power supplies output by the multiple flyback output transformers T1 is used as an excitation source of each forward transformer in the forward transformer set Tx to generate multiple IGBT driving power supplies. The forward control circuit 2 is configured to generate a PWM control square wave, and the PWM control square wave is used as a drive of the forward transformer, so that the excitation source can generate a plurality of IGBT drive power supplies through the forward control circuit 2 and the forward transformer in the forward transformer set Tx. Each IGBT driving power supply comprises a U-phase upper bridge driving power supply of the IGBT, a V-phase upper bridge driving power supply of the IGBT and a W-phase upper bridge driving power supply of the IGBT. And a plurality of IGBT drive power supplies are mutually independent, when one IGBT drive power supply fails, the whole driver cannot be completely unavailable, and the redundant design of the driver can be ensured.

In a more specific embodiment, the primary output circuit V1 includes a first diode D1, a second diode D2, a first electrolytic capacitor E1, and a first capacitor C1.

The anode of the first diode D1 and the anode of the second diode D2 are connected to the dotted terminal of the primary side second winding N2, the cathode of the first diode D1 and the cathode of the second diode D2 are connected to the anode of the first electrolytic capacitor E1 and the first terminal of the first capacitor C1, and the cathode of the first electrolytic capacitor E1, the second terminal of the first capacitor C1 and the dotted terminal of the primary side second winding N2 are grounded.

And a node connected with the cathode of the first diode D1, the cathode of the second diode D2, the anode of the first electrolytic capacitor E1 and the first end of the first capacitor C1 is used as an output end of the primary side output circuit V1 to output a first auxiliary power supply.

In this embodiment, referring to fig. 2, the primary side output circuit V1 can output +15V power according to the parameter settings of different elements in the primary side output circuit V1, that is, the first auxiliary power can be +15V power. For example, if the first electrolytic capacitor E1 is 220uF/35V and the first capacitor C1 is 104V, the output end of the primary side output circuit V1 can provide +15V power. The +15V power supply may supply power to the flyback control circuit 1, and may also supply power to other devices in the circuit. The +15V power supply supplies power to the forward control circuit 2, and outputs a multi-channel IGBT drive power supply as an excitation source of the forward transformer.

Further, the flyback control circuit 1 includes a switching power supply chip U1 and a peripheral circuit. Specifically, referring to fig. 2, the peripheral circuit includes a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a twenty-sixth capacitor C26, a twenty-seventh capacitor C27, a twenty-eighth capacitor C28, a twenty-ninth capacitor C29, a thirty-third capacitor C30, and a third fet M3.

A COMP pin of the switching power supply chip U1 is connected to a second end of a seventeenth resistor R17, a first end of the seventeenth resistor R17 is connected to a second end of a twenty-sixth capacitor C26, a first end of the twenty-sixth capacitor C26, an INV pin of the switching power supply chip U1, and a first end of the fourteenth resistor R14 are connected to a second end of the thirteenth resistor R13, a first end of the thirteenth resistor R13 is connected to the first auxiliary power supply, a second end of the fourteenth resistor R14 is grounded, a CT/RT pin of the switching power supply chip U1 is connected to a first end of a twenty-seventh capacitor C27 and a second end of the sixteenth resistor R16, a second end of the twenty-seventh capacitor C27 is grounded, a first end of the sixteenth resistor R16 is connected to a second end of the fifteenth resistor R15, a first end of the fifteenth resistor R15 is connected to a first end of the twenty-eighth capacitor C28, a second end of the switching power supply chip VREF pin, a first end of the twenty-eighth capacitor C28 is connected to a second end of the switching power supply, a drain terminal of the twenty-eighth capacitor C18, a gate terminal of the twenty-eighth capacitor C28, a drain terminal of the twenty-ninth resistor R3 is connected to the gate terminal of the twenty-eighth capacitor C19, a gate of the twenty-eighth capacitor C3, a gate terminal of the twenty-ninth resistor R18 is connected to the twenty-ninth resistor R18, a gate terminal of the twenty-ninth resistor R3, a gate of the twenty-ninth resistor R18 is connected to the gate of the twenty-ninth resistor R21, a first end of the twentieth resistor R20 is connected to the CS pin of the switching power supply chip U1 and a first end of the thirtieth capacitor C30, and a second end of the thirtieth capacitor C30, a second end of the twenty-first resistor R21, a second end of the twenty-second resistor R22, and the GND pin of the switching power supply chip U1 are grounded.

In this embodiment, referring to fig. 2, the flyback control circuit 1 can enable the primary side output circuit V1 to stably output power, and can generate a PWM control square wave for the forward control circuit 2 and each forward transformer in the forward transformer set Tx. The thirteenth resistor R13 and the fourteenth resistor R14 form a primary side voltage dividing circuit, and provide a reference voltage for an INV pin (i.e., pin 2) of the switching power supply chip U1, so that the primary side output circuit V1 can accurately output the first auxiliary power supply based on the reference voltage of the INV pin of the switching power supply chip U1. The model of the switching power supply chip U1 may adopt UC2844BD1R2G, and the first auxiliary power supply is a +15V power supply, then the resistances of the thirteenth resistor R13 and the fourteenth resistor R14 are respectively adopted as 15K Ω and 3K Ω, thereby providing a 2.5V reference voltage for the INV pin of the switching power supply chip U1, and the +15V power supply may supply power to the switching power supply chip U1, and may also supply power to other devices in the circuit, and meet the output requirement of 15V/0.3A. Meanwhile, the oscillation resistor-capacitor consists of a fifteenth resistor R15, a sixteenth resistor R16 and a twenty-seventh capacitor C27, the frequency is output through an OUT pin (namely 6 pins) of the switching power supply chip U1, and the peak current can be limited within the required current through a third field-effect transistor M3, an eighteenth resistor R18, a twenty-first resistor R21 and a twenty-second resistor R22. For example, the resistance values of the fifteenth resistor R15 and the sixteenth resistor R16 are 15K Ω and 1K Ω, respectively, the twenty-seventh capacitor C27 adopts 102 capacitors, the oscillation frequency is 107KHZ, the output frequency through the OUT pin (i.e., pin 6) of the switching power supply chip U1 is 54 KHZ, the third fet M3 adopts an IRFR014TRLPBF (60V/4.9A) switching tube, the resistance value of the eighteenth resistor R18 is 22 Ω, and the resistance values of the twenty-first resistor R21 and the twenty-second resistor R22 are 0.25 Ω and 0.25 Ω, respectively, so that the peak current can be limited to 8A to ensure that the output can be started with load.

Further, the primary side first winding N1 of the multi-path flyback output transformer T1 is coupled to a low voltage power supply, and the multi-path flyback output transformer T1 is supplied with power by the low voltage power supply. Specifically, referring to fig. 2, the low-voltage power supply may adopt a 24V power supply, and the auxiliary power supply circuit suitable for the driver provided in this embodiment includes a thirty-third electrolytic capacitor E33, a thirty-first capacitor C31, a thirty-second capacitor C32, a thirty-third capacitor C33, a twenty-third resistor R23, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a forty-third diode D43, a forty-fourth diode D44, a forty-fifth diode D45, and a forty-sixth diode D46. A 24V power supply is connected to the anodes of the forty-fifth diode D45 and the anodes of the forty-sixth diode D46, the cathodes of the forty-fifth diode D45 and the cathodes of the forty-sixth diode D46 are connected to the anodes of the thirty-third electrolytic capacitor E33, the first end of the thirty-third capacitor C33, the first end of the twenty-third resistor R23, the first end of the twenty-fourth resistor R24, the first end of the thirty-second capacitor C32, and the opposite terminal of the primary side first winding N1, the cathodes of the thirty-third electrolytic capacitor E33 and the second end of the thirty-third capacitor C33 are grounded, the second end of the twenty-third resistor R23, the first end of the thirty-third capacitor C31, and the cathodes of the forty-third diode D43 are connected to the pin of the switching power supply chip U1, the second end of the thirty-third capacitor C31 is grounded, the anode of the forty-third diode D43 is connected to the first auxiliary power supply, the cathode of the twenty-fourth diode R24 and the cathode of the twenty-fourth resistor R24 are connected to the anodes of the twenty-fifth diode D25, the second end of the twenty-fourth diode R25 is connected to the anode of the twenty-fourth diode R25 and the twenty-fourth diode R32.

In a more specific embodiment, the at least one secondary output circuit comprises a first secondary output circuit comprising a third diode D3, a fourth diode D4, a second electrolytic capacitor E2, a third electrolytic capacitor E3, a second capacitor C2, a third capacitor C3, and a first resistor R1.

The positive pole of the third diode D3 is connected with the dotted terminal of the corresponding first secondary winding N3, the negative pole of the third diode D3 is connected with the positive pole of the second electrolytic capacitor E2 and the first terminal of the second capacitor C2, the negative pole of the second electrolytic capacitor E2, the second terminal of the second capacitor C2, the positive pole of the third electrolytic capacitor E3, the first terminal of the third capacitor C3 and the first terminal of the first resistor R1 are connected with the corresponding dotted terminal of the first secondary winding N3, the negative pole of the third electrolytic capacitor E3, the second terminal of the third capacitor C3, the second terminal of the first resistor R1 are connected with the positive pole of the fourth diode D4, and the negative pole of the fourth diode D4 is connected with the dotted terminal N4 of the corresponding second secondary winding.

A node connecting the cathode of the third diode D3, the anode of the second electrolytic capacitor E2 and the first end of the second capacitor C2 serves as a first output end of the first secondary side output circuit to output a second auxiliary power supply; and a node connected with the anode of the fourth diode D4, the cathode of the third electrolytic capacitor E3, the second end of the third capacitor C3 and the second end of the first resistor R1 is used as a second output end of the first secondary side output circuit to output a third auxiliary power supply.

In this embodiment, referring to FIG. 2, the first secondary output circuit can output VB + power and VB power according to parameter settings of different elements in the first secondary output circuit. For example, the second electrolytic capacitor E2 is 100uF/25V, the third electrolytic capacitor E3 is 100uF/25V, the second capacitor C2 and the third capacitor C3 are 104 capacitors, and the first resistor R1 is 186.8K Ω, then the first output terminal of the first secondary output circuit can provide VB + power, the second output terminal of the first secondary output circuit can provide VB-power, that is, the second auxiliary power is VB + power, and the third auxiliary power is VB-power. The VB + power supply can be obtained by a voltage regulator tube, so that a positive power supply is provided for the lower bridge drive of the IGBT in the driver, and the VB-power supply provides a negative power supply for the lower bridge drive of the IGBT.

In a more specific embodiment, the at least one secondary side output circuit further comprises a second secondary side output circuit comprising a fifth diode D5, a first inductor L1, a fourth electrolytic capacitor E4, and a fourth capacitor C4.

The negative pole of the fifth diode D5 is connected with the synonym end of the corresponding secondary winding N5, the positive pole of the fifth diode D5 is connected with the first end of the first inductor L1, the second end of the first inductor L1 is connected with the negative pole of the fourth electrolytic capacitor E4 and the second end of the fourth capacitor C4, and the synonym end of the corresponding secondary winding N5, the positive pole of the fourth electrolytic capacitor E4 and the first end of the fourth capacitor C4 are grounded.

And a node connecting the second end of the first inductor L1, the cathode of the fourth electrolytic capacitor E4 and the second end of the fourth capacitor C4 is used as an output end of the second secondary side output circuit to output a fourth auxiliary power supply.

In this embodiment, referring to FIG. 2, the fourth auxiliary power supply may be a-15V power supply, depending on the parameter settings of the different elements in the second secondary output circuit. For example, in the present example, the first inductor L1 is 4.7uH/3A, the fourth electrolytic capacitor E4 is 100uF/25V, and the fourth capacitor C4 is 104V, the second secondary output circuit can provide-15V power.

In a more specific embodiment, the at least one secondary side output circuit further comprises a third secondary side output circuit comprising a sixth diode D6, a fifth electrolytic capacitor E5, a fifth capacitor C5 and a second resistor R2.

The positive electrode of the sixth diode D6 is connected to one end of the corresponding secondary winding N6, the negative electrode of the sixth diode D6 is connected to the positive electrode of the fifth electrolytic capacitor E5, the first end of the fifth capacitor C5 and the first end of the second resistor R2, and the negative electrode of the fifth electrolytic capacitor E5, the second end of the fifth capacitor C5 and the second end of the second resistor R2 are connected to the other end of the corresponding secondary winding N6.

And a node connecting the cathode of the sixth diode D6, the anode of the fifth electrolytic capacitor E5, the first end of the fifth capacitor C5 and the first end of the second resistor R2 is used as an output end of the third secondary side output circuit to output a fifth auxiliary power supply.

In this embodiment, referring to fig. 2, the secondary winding N6 connected to the third secondary output circuit is a fly winding of the multi-path flyback output transformer T1, and according to the parameter settings of different elements in the third secondary output circuit, a D24V power supply can be output. For example, if the fifth electrolytic capacitor E5 is 220uF/35V, the fifth capacitor C5 is 104V, and the second resistor R2 is 10K Ω, the third secondary output circuit can provide a D24V power supply. Wherein, the D24V power supply can provide an isolated power supply for the I/O port of the driver.

In a more specific embodiment, the forward control circuit 2 includes a timer chip U2, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9, a tenth capacitor C10, an eleventh capacitor C11, a twelfth capacitor C12, a thirteenth capacitor C13, a sixth electrolytic capacitor E6, a seventh electrolytic capacitor E7, an eighth electrolytic capacitor E8, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a first field effect transistor M1, and a second field effect transistor M2.

A first end of the sixth capacitor C6, a positive electrode of the sixth electrolytic capacitor E6, a first end of the third resistor R3, a VCC pin of the timer chip U2, and a RESET pin of the timer chip U2 are connected to the first auxiliary power supply, a second end of the third resistor R3 is connected to a first end of the fourth resistor R4, a second end of the fourth resistor R4 is connected to a first end of the fifth resistor R5, a second end of the fifth resistor R5 is connected to a first end of the seventh capacitor C7, a THOLD pin of the timer chip U2, a TRIG pin of the timer chip U2, and a first end of the sixth resistor R6, a second end of the seventh capacitor C7 is grounded to a GND pin of the timer chip U2, an OUT pin of the timer chip U2 is connected to a second end of the sixth resistor R6, a first end of the seventh resistor R7, and a first end of the tenth resistor R10, a second end of the seventh resistor R7 is connected to a first end of the eighth capacitor C8, a second end of the eighth capacitor C8 is connected to a second end of the eighth resistor R8 and the gate of the first fet M1, a second end of the tenth resistor R10 is connected to a first end of the ninth capacitor C9, a second end of the ninth capacitor C9 is connected to a first end of the eleventh resistor R11 and the gate of the second fet M2, a drain of the second fet M2 is connected to a drain of the first fet M1, a source of the first fet M1, a first end of the eighth resistor R8, a positive electrode of the seventh electrolytic capacitor E7, a first end of the twelfth capacitor C12 and a first end of the ninth resistor R9 are connected to the first auxiliary power supply, a negative electrode of the seventh electrolytic capacitor E7 is connected to a second end of the tenth capacitor C10, a gate of the tenth capacitor C10, and a drain of the tenth capacitor C9 are connected to the first auxiliary power supply, the second end of the eleventh capacitor C11, the positive electrode of the eighth electrolytic capacitor E8, the second end of the twelfth capacitor C12, the second end of the ninth resistor R9, the first end of the thirteenth capacitor C13 and the first end of the twelfth resistor R12 are connected, the first end of the tenth capacitor C10 and the first end of the eleventh capacitor C11 are connected, and the second end of the eleventh resistor R11, the source of the second field effect transistor M2, the negative electrode of the eighth electrolytic capacitor E8, the second end of the thirteenth capacitor C13 and the second end of the twelfth resistor R12 are grounded.

A node connecting the drain of the second field effect transistor M2 and the drain of the first field effect transistor M1 is used as a first output terminal a of the forward control circuit 2, and a node connecting the first end of the tenth capacitor C10 and the first end of the eleventh capacitor C11 is used as a second output terminal B of the forward control circuit 2.

In this embodiment, referring to fig. 3, the first output terminal a and the second output terminal B of the forward control circuit 2 are respectively connected to two ends of the primary input winding of each forward transformer in the forward transformer set Tx, and voltages of the first output terminal a and the second output terminal B of the forward control circuit 2 can be balanced on the required varying square wave pulse. For example, the model of the timer chip U2 may adopt MC1455BDR2G, based on that the timer chip U2 can generate PWM with fixed frequency and duty ratio to drive the forward power supply, the oscillation resistor-capacitor is composed of a third resistor R3, a fourth resistor R4, a fifth resistor R5 and a seventh capacitor C7, when the third resistor R3 is 51K Ω, the fourth resistor R4 is 22K Ω, the fifth resistor R5 is 12K Ω, and the seventh capacitor C7 is 102 capacitors, a square wave with oscillation frequency of 120KHZ, output duty ratio of 50% and amplitude of 15V is generated, the OUT pin (i.e. 3 pins) of the timer chip U2 outputs a pair of push-pull, the first field effect transistor M1 and the second field effect transistor M2 can be respectively made of IRFR9014TRPBF and IRFR014TRPBF, input stages of the two transistors are connected with blocking capacitors, namely an eighth capacitor C8 and a ninth capacitor C9, the eighth capacitor C8 and the ninth capacitor C9 are 104 capacitors, so that a 15V square wave is converted into a ± 7.5V square wave to respectively drive the first field effect transistor M1 and the second field effect transistor M2, and the voltages of the first output end a of the forward control circuit 2 and the second output end B (namely, two points AB) of the forward control circuit 2 can be ensured to be balanced in a variation square wave pulse of ± 7.5 through a tenth capacitor C10 and an eleventh capacitor C11. The first output end a and the second output end B of the forward control circuit 2 are respectively connected with two ends of the primary input winding of each forward transformer in the forward transformer set Tx, so that the output end of each forward transformer can form a voltage doubling circuit by a diode and a capacitor to obtain a target voltage.

In a more specific embodiment, the forward transformer set Tx includes a first forward transformer T2, and the first forward transformer T2 includes a primary input first winding N7, a primary first winding N8, a secondary first winding N9, a secondary second winding N10, a first W-phase upper bridge driving power supply circuit V1W1, a first U-phase upper bridge driving power supply circuit V1U1, and a first V-phase upper bridge driving power supply circuit V1.

The homonymous terminal of the primary input first winding N7 is connected to the first output terminal a of the forward control circuit 2, and the synonym terminal of the primary input first winding N7 is connected to the second output terminal B of the forward control circuit 2.

The first W-phase upper bridge driving power supply circuit V1W1 includes a ninth electrolytic capacitor E9, a tenth electrolytic capacitor E10, a seventh diode D7, an eighth diode D8, a ninth diode D9, and a fourteenth capacitor C14, a second end of the fourteenth capacitor C14 and a negative electrode of the ninth diode D9 are connected to a same-name end of the primary first winding N8, a first end of the fourteenth capacitor C14 is connected to a positive electrode of the seventh diode D7 and a negative electrode of the eighth diode D8, a negative electrode of the seventh diode D7 is connected to a positive electrode of the ninth electrolytic capacitor E9, a positive electrode of the eighth diode D8 is connected to a negative electrode of the ninth electrolytic capacitor E9, a positive electrode of the tenth electrolytic capacitor E10 and a different-name end of the primary first winding N8, and a negative electrode of the tenth electrolytic capacitor E10 is connected to a positive electrode of the ninth diode D9.

The first U-phase upper bridge driving power supply circuit V1U1 comprises a fifteenth capacitor C15, a twelfth diode D10, an eleventh diode D11, a twelfth diode D12, an eleventh electrolytic capacitor E11 and a twelfth electrolytic capacitor E12; a first end of the fifteenth capacitor C15 and a cathode of the twelfth diode D12 are connected to the dotted terminal of the secondary first winding N9, a second end of the fifteenth capacitor C15 is connected to a cathode of the twelfth diode D10 and an anode of the eleventh diode D11, an anode of the twelfth diode D10, a cathode of the eleventh electrolytic capacitor E11 and an anode of the twelfth electrolytic capacitor E12 are connected to the dotted terminal of the secondary first winding N9, a cathode of the eleventh diode D11 is connected to an anode of the eleventh electrolytic capacitor E11, and an anode of the twelfth diode D12 is connected to a cathode of the twelfth electrolytic capacitor E12.

The first V-phase upper bridge driving power supply circuit V1V1 comprises a sixteenth capacitor C16, a thirteenth diode D13, a fourteenth diode D14, a fifteenth diode D15, a thirteenth electrolytic capacitor E13 and a fourteenth electrolytic capacitor E14; a first end of the sixteenth capacitor C16 and a cathode of the fifteenth diode D15 are connected to the dotted terminal of the secondary second winding N10, a second end of the sixteenth capacitor C16 is connected to a cathode of the thirteenth diode D13 and an anode of the fourteenth diode D14, an anode of the thirteenth diode D13, a cathode of the thirteenth electrolytic capacitor E13 and an anode of the fourteenth electrolytic capacitor E14 are connected to the dotted terminal of the secondary second winding N10, a cathode of the fourteenth diode D14 is connected to an anode of the thirteenth electrolytic capacitor E13, and an anode of the fifteenth diode D15 is connected to a cathode of the fourteenth electrolytic capacitor E14.

In this embodiment, referring to fig. 4, a voltage doubling circuit is formed by diodes and capacitors in the first W-phase upper bridge driving power supply V1W1, the first U-phase upper bridge driving power supply V1U1 and the first V-phase upper bridge driving power supply V1 to obtain a target voltage, so that the first forward transformer T2 can provide the W-phase upper bridge driving power supply V1W1 ± of the first IGBT, the U-phase upper bridge driving power supply V1U1 ± and the V-phase upper bridge driving power supply V1 ±, respectively. A node connecting the negative electrode of the seventh diode D7 and the positive electrode of the ninth electrolytic capacitor E9 serves as an output terminal of the W-phase upper bridge driving positive power supply V1W1+ of the first IGBT, and a node connecting the negative electrode of the tenth electrolytic capacitor E10 and the positive electrode of the ninth diode D9 serves as an output terminal of the W-phase upper bridge driving negative power supply V1W 1-of the first IGBT; a node connecting the negative electrode of the eleventh diode D11 and the positive electrode of the eleventh electrolytic capacitor E11 serves as an output end of the U-phase upper bridge driving positive power supply V1U1+ of the first IGBT, and a node connecting the positive electrode of the twelfth diode D12 and the negative electrode of the twelfth electrolytic capacitor E12 serves as an output end of the U-phase upper bridge driving negative power supply V1U 1-of the first IGBT; a node connecting the cathode of the fourteenth diode D14 and the anode of the thirteenth electrolytic capacitor E13 serves as an output terminal of the V-phase upper bridge driving positive power supply V1+ of the first IGBT, and a node connecting the anode of the fifteenth diode D15 and the cathode of the fourteenth electrolytic capacitor E14 serves as an output terminal of the V-phase upper bridge driving negative power supply V1-of the first IGBT. The U-phase upper bridge driving power supply of the first IGBT comprises a U-phase upper bridge driving positive power supply V1U1+ of the first IGBT and a U-phase upper bridge driving negative power supply V1U 1-of the first IGBT, the U-phase upper bridge driving positive power supply V1U1+ of the first IGBT is obtained by a voltage doubling circuit consisting of an eleventh diode D11, a twelfth diode D12 and a fifteenth capacitor C15, the U-phase upper bridge driving positive power supply V1U1+ of the first IGBT is a 15V upper bridge driving positive power supply, the U-phase upper bridge driving negative power supply V1U 1-of the first IGBT is obtained by a loop consisting of the twelfth diode D12, and the U-phase upper bridge driving negative power supply V1U 1-of the first IGBT is a-7.5V upper bridge driving negative power supply. Meanwhile, the principle of obtaining the V-phase upper bridge driving power supply and the W-phase upper bridge driving power supply of the first IGBT is the same as that of the first IGBT.

In a more specific embodiment, the forward transformer set Tx further includes a second forward transformer T3, and the second forward transformer T3 includes a primary input second winding N11, a primary second winding N12, a secondary third winding N13, a secondary fourth winding N14, a second W-phase upper bridge driving power supply circuit V2W2, a second U-phase upper bridge driving power supply circuit V2U2, and a second V-phase upper bridge driving power supply circuit V2.

The homonymous terminal of the primary-side input second winding N11 is connected to the first output terminal a of the forward control circuit 2, and the synonym terminal of the primary-side input second winding N11 is connected to the second output terminal B of the forward control circuit 2.

The second W-phase upper bridge driving power supply circuit V2W2 includes a fifteenth electrolytic capacitor E15, a sixteenth electrolytic capacitor E16, a sixteenth diode D16, a seventeenth diode D17, an eighteenth diode D18 and a seventeenth capacitor C17, wherein a second end of the seventeenth capacitor C17 and a cathode of the eighteenth diode D18 are connected to a same-name end of the primary second winding N12, a first end of the seventeenth capacitor C17 is connected to an anode of the sixteenth diode D16 and a cathode of the seventeenth diode D17, a cathode of the sixteenth diode D16 is connected to an anode of the fifteenth electrolytic capacitor E15, an anode of the seventeenth diode D17 is connected to a cathode of the fifteenth electrolytic capacitor E15, an anode of the sixteenth electrolytic capacitor E16 and a different-name end of the primary second winding N12, and a cathode of the sixteenth electrolytic capacitor E16 is connected to an anode of the eighteenth diode D18.

The second U-phase upper bridge driving power supply circuit V2U2 includes an eighteenth capacitor C18, a nineteenth diode D19, a twentieth diode D20, a twenty-first diode D21, a seventeenth electrolytic capacitor E17, and an eighteenth electrolytic capacitor E18; the first end of the eighteenth capacitor C18 and the cathode of the twenty-first diode D21 are connected to the end with the same name of the secondary third winding N13, the second end of the eighteenth capacitor C18 is connected to the cathode of the nineteenth diode D19 and the anode of the twentieth diode D20, the anode of the nineteenth diode D19, the cathode of the seventeenth electrolytic capacitor E17 and the anode of the eighteenth electrolytic capacitor E18 are connected to the end with different name of the secondary third winding N13, the cathode of the twentieth diode D20 is connected to the anode of the seventeenth electrolytic capacitor E17, and the anode of the twenty-first diode D21 is connected to the cathode of the eighteenth electrolytic capacitor E18.

The second V-phase upper bridge driving power supply circuit V2 comprises a nineteenth capacitor C19, a twenty-second diode D22, a twenty-third diode D23, a twenty-fourth diode D24, a nineteenth electrolytic capacitor E19 and a twentieth electrolytic capacitor E20; the first end of the nineteenth capacitor C19 and the cathode of the twenty-fourth diode D24 are connected to the dotted terminal of the secondary fourth winding N14, the second end of the nineteenth capacitor C19 is connected to the cathode of the twenty-second diode D22 and the anode of the twenty-third diode D23, the anode of the twenty-second diode D22, the cathode of the nineteenth electrolytic capacitor E19 and the anode of the twentieth electrolytic capacitor E20 are connected to the dotted terminal of the secondary fourth winding N14, the cathode of the twenty-third diode D23 is connected to the anode of the nineteenth electrolytic capacitor E19, and the anode of the twenty-fourth diode D24 is connected to the cathode of the twentieth electrolytic capacitor E20.

In this embodiment, referring to fig. 4, the same principle as that of the first forward transformer T2 is adopted, a voltage doubling circuit is formed by diodes and capacitors in the second W-phase upper bridge driving power supply circuit V2W2, the second U-phase upper bridge driving power supply circuit V2U2 and the second V-phase upper bridge driving power supply circuit V2 to obtain a target voltage, and the second forward transformer T3 can provide the W-phase upper bridge driving power supply V2W2 ± of the second IGBT, the U-phase upper bridge driving power supply V2U2 ± and the V-phase upper bridge driving power supply V2 ± (V2). A node between the negative electrode of the sixteenth diode D16 and the positive electrode of the fifteenth electrolytic capacitor E15 is connected as an output terminal of the W-phase up-bridge driving positive power supply V2W2+ of the second IGBT, and a node between the negative electrode of the sixteenth electrolytic capacitor E16 and the positive electrode of the eighteenth diode D18 is connected as an output terminal of the W-phase up-bridge driving negative power supply V2W 2-of the second IGBT; a node connecting the cathode of the twentieth diode D20 and the anode of the seventeenth electrolytic capacitor E17 serves as an output terminal of a U-phase upper bridge driving positive power supply V2U2+ of the second IGBT, and a node connecting the anode of the twenty first diode D21 and the cathode of the eighteenth electrolytic capacitor E18 serves as an output terminal of a U-phase upper bridge driving negative power supply V2U 2-of the second IGBT; and a node connecting the cathode of the twenty-third diode D23 and the anode of the nineteenth electrolytic capacitor E19 serves as an output terminal of the V-phase upper bridge driving positive power supply V2+ of the second IGBT, and a node connecting the anode of the twenty-fourth diode D24 and the cathode of the twentieth electrolytic capacitor E20 serves as an output terminal of the V-phase upper bridge driving negative power supply V2-of the second IGBT.

In a more specific embodiment, the forward transformer set Tx further includes a third forward transformer T4 and a fourth forward transformer T5.

The third forward transformer T4 includes a primary input third winding N15, a primary third winding N16, a secondary fifth winding N17, a secondary sixth winding N18, a third W-phase upper bridge driving power supply circuit V3W3, a third U-phase upper bridge driving power supply circuit V3U3, and a third V-phase upper bridge driving power supply circuit V3.

The homonymous end of the primary-side input third winding N15 is connected with the first output end A of the forward control circuit 2, and the synonym end of the primary-side input third winding N15 is connected with the second output end B of the forward control circuit 2;

the third W-phase upper bridge driving power supply circuit V3W3 includes a twenty-first electrolytic capacitor E21, a twenty-second electrolytic capacitor E22, a twenty-fifth diode D25, a twenty-sixth diode D26, a twenty-seventh diode D27 and a twentieth capacitor C20, a second end of the twentieth capacitor C20 and a cathode of the twenty-seventh diode D27 are connected to a dotted terminal of the primary third winding N16, a first end of the twentieth capacitor C20 is connected to an anode of the twenty-fifth diode D25 and a cathode of the twenty-sixth diode D26, a cathode of the twenty-fifth diode D25 is connected to an anode of the twenty-first electrolytic capacitor E21, an anode of the twenty-sixth diode D26 is connected to a cathode of the twenty-first electrolytic capacitor E21, an anode of the twenty-second electrolytic capacitor E22 and a dotted terminal of the primary third winding N16, and a cathode of the twenty-second electrolytic capacitor E22 and an anode of the twenty-seventh diode D27 are connected to a dotted terminal of the primary third winding N16.

The third U-phase upper bridge driving power supply circuit V3U3 includes a twenty-first capacitor C21, a twenty-eighth diode D28, a twenty-ninth diode D29, a thirtieth diode D30, a twenty-third electrolytic capacitor E23, and a twenty-fourth electrolytic capacitor E24; the first end of the twenty-first capacitor C21 and the cathode of the thirty-second diode D30 are connected to the dotted terminal of the secondary fifth winding N17, the second end of the twenty-first capacitor C21 is connected to the cathode of the twenty-eighth diode D28 and the anode of the twenty-ninth diode D29, the anode of the twenty-eighth diode D28, the cathode of the twenty-third electrolytic capacitor E23 and the anode of the twenty-fourth electrolytic capacitor E24 are connected to the dotted terminal of the secondary fifth winding N17, the cathode of the twenty-ninth diode D29 is connected to the anode of the twenty-third electrolytic capacitor E23, and the anode of the thirty-second diode D30 is connected to the cathode of the twenty-fourth electrolytic capacitor E24.

The third V-phase upper bridge driving power supply circuit V3V3 comprises a twenty-second capacitor C22, a thirty-first diode D31, a thirty-second diode D32, a thirty-third diode D33, a twenty-fifth electrolytic capacitor E25 and a twenty-sixth electrolytic capacitor E26; a first end of the twenty-second capacitor C22 and a cathode of the thirty-third diode D33 are connected to the dotted end of the secondary sixth winding N18, a second end of the twenty-second capacitor C22 is connected to a cathode of the thirty-first diode D31 and an anode of the thirty-second diode D32, an anode of the thirty-first diode D31, a cathode of the twenty-fifth electrolytic capacitor E25 and an anode of the twenty-sixth electrolytic capacitor E26 are connected to the dotted end of the secondary sixth winding N18, a cathode of the thirty-second diode D32 is connected to an anode of the twenty-fifth electrolytic capacitor E25, and an anode of the thirty-third diode D33 is connected to a cathode of the twenty-sixth electrolytic capacitor E26.

The fourth forward transformer T5 includes a primary-side input fourth winding N19, a primary fourth winding N20, a secondary seventh winding N21, a secondary eighth winding N22, a fourth W-phase upper bridge driving power supply circuit V4W4, a fourth U-phase upper bridge driving power supply circuit V4U4, and a fourth V-phase upper bridge driving power supply circuit V4.

The dotted terminal of the primary side input fourth winding N19 is connected to the first output terminal a of the forward control circuit 2, and the dotted terminal of the primary side input fourth winding N19 is connected to the second output terminal B of the forward control circuit 2.

The fourth W-phase upper bridge driving power supply circuit V4W4 includes a twenty-seventh electrolytic capacitor E27, a twenty-eighth electrolytic capacitor E28, a thirty-fourth diode D34, a thirty-fifth diode D35, a thirty-sixth diode D36, and a twenty-third capacitor C23, a second end of the twenty-third capacitor C23 and a cathode of the thirty-sixth diode D36 are connected to a same-name end of the primary fourth winding N20, a first end of the twenty-third capacitor C23 is connected to an anode of the thirty-fourth diode D34 and a cathode of the thirty-fifth diode D35, a cathode of the thirty-fourth diode D34 is connected to an anode of the twenty-seventh electrolytic capacitor E27, an anode of the thirty-fifth diode D35 is connected to a cathode of the twenty-seventh electrolytic capacitor E27, an anode of the twenty-eighth electrolytic capacitor E28, and a different-name end of the primary fourth winding N20, and a cathode of the twenty-eighth electrolytic capacitor E28 and a cathode of the thirty-sixth diode D36 are connected.

The fourth U-phase upper bridge driving power supply circuit V4U4 comprises a twenty-fourth capacitor C24, a thirty-seventh diode D37, a thirty-eighth diode D38, a thirty-ninth diode D39, a twenty-ninth electrolytic capacitor E29 and a thirty-ninth electrolytic capacitor E30; a first end of the twenty-fourth capacitor C24 and a cathode of the thirty-ninth diode D39 are connected to the same-name end of the secondary seventh winding N21, a second end of the twenty-fourth capacitor C24 is connected to a cathode of the thirty-seventh diode D37 and an anode of the thirty-eighth diode D38, an anode of the thirty-seventh diode D37, a cathode of the twenty-ninth electrolytic capacitor E29 and an anode of the thirty-eighth electrolytic capacitor E30 are connected to the different-name end of the secondary seventh winding N21, a cathode of the thirty-eighth diode D38 is connected to an anode of the twenty-ninth electrolytic capacitor E29, and an anode of the thirty-ninth diode D39 is connected to a cathode of the thirty-ninth electrolytic capacitor E30.

The fourth V-phase upper bridge driving power supply circuit V4V4 comprises a twenty-fifth capacitor C25, a forty-fifth diode D40, a forty-second diode D41, a forty-second diode D42, a thirty-first electrolytic capacitor E31 and a thirty-second electrolytic capacitor E32; the first end of the twenty-fifth capacitor C25 and the cathode of the forty-second diode D42 are connected to the dotted terminal of the secondary eighth winding N22, the second end of the twenty-fifth capacitor C25 is connected to the cathode of the forty-second diode D40 and the anode of the forty-second diode D41, the anode of the forty-second diode D40, the cathode of the thirty-first electrolytic capacitor E31 and the anode of the thirty-second electrolytic capacitor E32 are connected to the dotted terminal of the secondary eighth winding N22, the cathode of the forty-second diode D41 is connected to the anode of the thirty-first electrolytic capacitor E31, and the anode of the forty-second diode D42 is connected to the cathode of the thirty-second electrolytic capacitor E32.

In this embodiment, referring to fig. 4, the same principle as that of the first forward transformer T2 is adopted, a voltage doubling circuit is formed by diodes and capacitors in the third W-phase upper bridge driving power supply circuit V3W3, the third U-phase upper bridge driving power supply circuit V3U3 and the third V-phase upper bridge driving power supply circuit V3 to obtain a target voltage, and the third forward transformer T4 can provide the W-phase upper bridge driving power supply V3W3 ± of the third IGBT, the U-phase upper bridge driving power supply V3U3 ± and the V-phase upper bridge driving power supply V3 ±. A node connecting the negative electrode of the twenty-fifth diode D25 and the positive electrode of the twenty-first electrolytic capacitor E21 serves as an output end of a W-phase over-bridge driving positive power supply V3W3+ of the third IGBT, and a node connecting the negative electrode of the twenty-second electrolytic capacitor E22 and the positive electrode of the twenty-seventh diode D27 serves as an output end of a W-phase over-bridge driving negative power supply V3W 3-of the third IGBT; a node connecting the cathode of the twenty-ninth diode D29 and the anode of the twenty-third electrolytic capacitor E23 serves as an output end of a U-phase over-bridge driving positive power supply V3U3+ of the third IGBT, and a node connecting the anode of the thirtieth diode D30 and the cathode of the twenty-fourth electrolytic capacitor E24 serves as an output end of a U-phase over-bridge driving negative power supply V3U 3-of the third IGBT; and a node connecting the cathode of the thirty-second diode D32 and the anode of the twenty-fifth electrolytic capacitor E25 serves as an output end of a V-phase upper bridge driving positive power supply V3+ of the third IGBT, and a node connecting the anode of the thirty-third diode D33 and the cathode of the twenty-sixth electrolytic capacitor E26 serves as an output end of a V-phase upper bridge driving negative power supply V3-of the third IGBT.

The same principle as the first forward transformer T2, a voltage doubling circuit is formed by diodes and capacitors in the fourth W-phase upper bridge driving power supply circuit V4W4, the fourth U-phase upper bridge driving power supply circuit V4U4 and the fourth V-phase upper bridge driving power supply circuit V4 to obtain a target voltage, and the fourth forward transformer T5 can provide the W-phase upper bridge driving power supply V4W4 ± of the fourth IGBT, the U-phase upper bridge driving power supply V4U4 ± and the V-phase upper bridge driving power supply V4 ± of the fourth IGBT. A node connecting the negative electrode of the thirty-fourth diode D34 and the positive electrode of the twenty-seventh electrolytic capacitor E27 serves as an output terminal of the W-phase up-bridge driving positive power supply V4W4+ of the fourth IGBT, and a node connecting the negative electrode of the twenty-eighth electrolytic capacitor E28 and the positive electrode of the thirty-sixth diode D36 serves as an output terminal of the W-phase up-bridge driving negative power supply V4W 4-of the fourth IGBT; a node connecting the cathode of the thirty-eighth diode D38 and the anode of the twenty-ninth electrolytic capacitor E29 serves as an output end of a U-phase over-bridge driving positive power supply V4U4+ of the fourth IGBT, and a node connecting the anode of the thirty-ninth diode D39 and the cathode of the thirty-ninth electrolytic capacitor E30 serves as an output end of a U-phase over-bridge driving negative power supply V4U 4-of the fourth IGBT; and a node connecting the cathode of the forty-second diode D41 and the anode of the thirty-first electrolytic capacitor E31 serves as an output end of a V-phase upper bridge driving positive power supply V4+ of the fourth IGBT, and a node connecting the anode of the forty-second diode D42 and the cathode of the thirty-second electrolytic capacitor E32 serves as an output end of a V-phase upper bridge driving negative power supply V4-of the fourth IGBT.

The invention provides an auxiliary power supply circuit suitable for a driver, which comprises: the flyback control circuit and the multi-path flyback output transformer; the multi-path flyback output transformer comprises a primary side first winding, a primary side second winding, a primary side output circuit, a secondary side winding set and a secondary side output circuit set; the primary side output circuit is connected with the primary side second winding, the secondary side winding set comprises at least one secondary side winding, the secondary side output circuit set comprises at least one secondary side output circuit, and the at least one secondary side output circuit is correspondingly connected with the at least one secondary side winding respectively; one end of the primary side first winding is coupled with the low-voltage power supply, and the other end of the primary side first winding is coupled with the flyback control circuit, so that the multi-path flyback output transformer outputs at least two auxiliary power supplies through the primary side output circuit and the secondary side output circuit. The invention can provide an auxiliary power supply with low voltage power supply, can avoid the problem of misoperation failure caused by high voltage power supply on the driver, and can reduce the production cost.

While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. An auxiliary power supply circuit for a driver, comprising: the flyback control circuit and the multi-channel flyback output transformer;

the multi-path flyback output transformer comprises a primary side first winding, a primary side second winding, a primary side output circuit, a secondary side winding set and a secondary side output circuit set; the primary side output circuit is connected with the primary side second winding, the secondary side winding set comprises at least one secondary side winding, the at least one secondary side winding is coupled with the primary side first winding and the primary side second winding, the secondary side output circuit set comprises at least one secondary side output circuit, and the at least one secondary side output circuit and the at least one secondary side winding are respectively and correspondingly connected;

2. The auxiliary power supply circuit for the driver as claimed in claim 1, wherein any one of the at least two auxiliary power supplies is connected to a forward control circuit, and the forward control circuit is connected to a forward transformer set; the forward transformer set comprises at least one forward transformer, and the forward transformer is used for outputting an IGBT driving power supply.

3. The auxiliary power supply circuit for a driver as claimed in claim 2, wherein said primary side output circuit comprises a first diode, a second diode, a first electrolytic capacitor and a first capacitor;

the anode of the first diode and the anode of the second diode are connected with the dotted terminal of the primary side second winding, the cathode of the first diode and the cathode of the second diode are connected with the anode of the first electrolytic capacitor and the first terminal of the first capacitor, and the cathode of the first electrolytic capacitor, the second terminal of the first capacitor and the dotted terminal of the primary side second winding are grounded;

and a node connected with the cathode of the first diode, the cathode of the second diode, the anode of the first electrolytic capacitor and the first end of the first capacitor is used as an output end of the primary side output circuit to output a first auxiliary power supply.

4. An auxiliary power supply circuit for a driver as claimed in claim 3, wherein said at least one secondary output circuit comprises a first secondary output circuit comprising a third diode, a fourth diode, a second electrolytic capacitor, a third electrolytic capacitor, a second capacitor, a third capacitor and a first resistor;

the anode of the third diode is connected with the dotted terminal of the corresponding first secondary winding, the cathode of the third diode is connected with the anode of the second electrolytic capacitor and the first terminal of the second capacitor, the cathode of the second electrolytic capacitor, the second terminal of the second capacitor, the anode of the third electrolytic capacitor, the first terminal of the third capacitor and the first terminal of the first resistor are connected with the corresponding dotted terminal of the first secondary winding, the cathode of the third electrolytic capacitor, the second terminal of the third capacitor and the second terminal of the first resistor are connected with the anode of the fourth diode, and the cathode of the fourth diode is connected with the dotted terminal of the corresponding second secondary winding;

5. The auxiliary power supply circuit for a driver of claim 4, wherein said at least one secondary output circuit further comprises a second secondary output circuit, said second secondary output circuit comprising a fifth diode, a first inductor, a fourth electrolytic capacitor, and a fourth capacitor;

the negative electrode of the fifth diode is connected with the synonym end of the corresponding secondary winding, the positive electrode of the fifth diode is connected with the first end of the first inductor, the second end of the first inductor is connected with the negative electrode of the fourth electrolytic capacitor and the second end of the fourth capacitor, and the synonym end of the corresponding secondary winding, the positive electrode of the fourth electrolytic capacitor and the first end of the fourth capacitor are grounded;

6. The auxiliary power supply circuit for a driver as claimed in claim 5, wherein said at least one secondary side output circuit further comprises a third secondary side output circuit, said third secondary side output circuit comprising a sixth diode, a fifth electrolytic capacitor, a fifth capacitor and a second resistor;

the anode of the sixth diode is connected with one end of the corresponding secondary winding, the cathode of the sixth diode is connected with the anode of the fifth electrolytic capacitor, the first end of the fifth capacitor and the first end of the second resistor, and the cathode of the fifth electrolytic capacitor, the second end of the fifth capacitor and the second end of the second resistor are connected with the other end of the corresponding secondary winding;

7. The auxiliary power supply circuit for the driver as claimed in claim 3, wherein the forward control circuit comprises a timer chip, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, a thirteenth capacitor, a sixth electrolytic capacitor, a seventh electrolytic capacitor, an eighth electrolytic capacitor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a first FET and a second FET;

the first end of the sixth capacitor, the positive electrode of the sixth electrolytic capacitor, the first end of the third resistor, the VCC pin of the timer chip and the RESET pin of the timer chip are connected to the first auxiliary power supply, the second end of the third resistor is connected to the first end of the fourth resistor, the second end of the fourth resistor is connected to the first end of the fifth resistor, the second end of the fifth resistor is connected to the first end of the seventh capacitor, the THOLD pin of the timer chip, the TRIG pin of the timer chip and the first end of the sixth resistor, the second end of the seventh capacitor is grounded to the GND pin of the timer chip, the OUT pin of the timer chip is connected to the second end of the sixth resistor, the first end of the seventh resistor and the first end of the tenth resistor, the second end of the seventh resistor is connected to the first end of the eighth capacitor, a second end of the eighth capacitor is connected with a second end of the eighth resistor and the gate of the first field effect transistor, a second end of the tenth resistor is connected with a first end of the ninth capacitor, a second end of the ninth capacitor is connected with a first end of the eleventh resistor and the gate of the second field effect transistor, a drain of the second field effect transistor is connected with a drain of the first field effect transistor, a source of the first field effect transistor, a first end of the eighth resistor, an anode of the seventh electrolytic capacitor, a first end of the twelfth capacitor and a first end of the ninth resistor are connected with the first auxiliary power supply, a cathode of the seventh electrolytic capacitor is connected with a second end of the tenth capacitor, a second end of the eleventh capacitor, an anode of the eighth electrolytic capacitor, a second end of the twelfth capacitor, a drain of the twelfth capacitor, A second end of the ninth resistor, a first end of the thirteenth capacitor and a first end of the twelfth resistor are connected, a first end of the tenth capacitor and a first end of the eleventh capacitor are connected, a second end of the eleventh resistor, a source electrode of the second field effect transistor, a cathode of the eighth electrolytic capacitor, a second end of the thirteenth capacitor and a second end of the twelfth resistor are grounded;

8. The auxiliary power supply circuit suitable for the driver of claim 7, wherein the forward transformer set comprises a first forward transformer, the first forward transformer comprising a primary input first winding, a primary first winding, a secondary second winding, a first W-phase upper bridge driving power supply circuit, a first U-phase upper bridge driving power supply circuit and a first V-phase upper bridge driving power supply circuit;

the homonymous end of the primary side input first winding is connected with the first output end of the forward control circuit, and the heteronymous end of the primary side input first winding is connected with the second output end of the forward control circuit;

the first W-phase upper bridge driving power supply circuit comprises a ninth electrolytic capacitor, a tenth electrolytic capacitor, a seventh diode, an eighth diode, a ninth diode and a fourteenth capacitor, wherein a second end of the fourteenth capacitor and a cathode of the ninth diode are connected with a dotted terminal of the primary first winding, a first end of the fourteenth capacitor is connected with an anode of the seventh diode and a cathode of the eighth diode, a cathode of the seventh diode is connected with an anode of the ninth electrolytic capacitor, an anode of the eighth diode is connected with a cathode of the ninth electrolytic capacitor, an anode of the tenth electrolytic capacitor and a dotted terminal of the primary first winding, and a cathode of the tenth electrolytic capacitor is connected with an anode of the ninth diode;

the first U-phase upper bridge driving power supply circuit comprises a fifteenth capacitor, a twelfth diode, an eleventh diode, a twelfth diode, an eleventh electrolytic capacitor and a twelfth electrolytic capacitor; the first end of the fifteenth capacitor and the cathode of the twelfth diode are connected with the dotted terminal of the secondary first winding, the second end of the fifteenth capacitor is connected with the cathode of the twelfth diode and the anode of the eleventh diode, the anode of the twelfth diode, the cathode of the eleventh electrolytic capacitor and the anode of the twelfth electrolytic capacitor are connected with the dotted terminal of the secondary first winding, the cathode of the eleventh diode is connected with the anode of the eleventh electrolytic capacitor, and the anode of the twelfth diode is connected with the cathode of the twelfth electrolytic capacitor;

9. The auxiliary power supply circuit for the driver of claim 8, wherein the forward transformer set further comprises a second forward transformer, and the second forward transformer comprises a primary input second winding, a primary second winding, a secondary third winding, a secondary fourth winding, a second W-phase upper bridge driving power supply circuit, a second U-phase upper bridge driving power supply circuit, and a second V-phase upper bridge driving power supply circuit;

the homonymous end of the primary side input second winding is connected with the first output end of the forward control circuit, and the heteronymous end of the primary side input second winding is connected with the second output end of the forward control circuit;

the second W-phase upper bridge driving power supply circuit comprises a fifteenth electrolytic capacitor, a sixteenth diode, a seventeenth diode, an eighteenth diode and a seventeenth capacitor, wherein a second end of the seventeenth capacitor and a cathode of the eighteenth diode are connected with the same-name end of the primary second winding, a first end of the seventeenth capacitor is connected with an anode of the sixteenth diode and a cathode of the seventeenth diode, a cathode of the sixteenth diode is connected with an anode of the fifteenth electrolytic capacitor, an anode of the seventeenth diode is connected with a cathode of the fifteenth electrolytic capacitor, an anode of the sixteenth electrolytic capacitor and a different-name end of the primary second winding, and a cathode of the sixteenth electrolytic capacitor is connected with an anode of the eighteenth diode;

the second U-phase upper bridge driving power supply circuit comprises an eighteenth capacitor, a nineteenth diode, a twentieth diode, a twenty-first diode, a seventeenth electrolytic capacitor and an eighteenth electrolytic capacitor; the first end of the eighteenth capacitor and the cathode of the twenty-first diode are connected with the dotted terminal of the secondary third winding, the second end of the eighteenth capacitor is connected with the cathode of the nineteenth diode and the anode of the twentieth diode, the anode of the nineteenth diode, the cathode of the seventeenth electrolytic capacitor and the anode of the eighteenth electrolytic capacitor are connected with the dotted terminal of the secondary third winding, the cathode of the twentieth diode is connected with the anode of the seventeenth electrolytic capacitor, and the anode of the twenty-first diode is connected with the cathode of the eighteenth electrolytic capacitor;

10. The auxiliary power supply circuit for a driver as claimed in claim 9, wherein said set of forward transformers further comprises a third forward transformer and a fourth forward transformer;

the third forward transformer comprises a primary input third winding, a primary third winding, a secondary fifth winding, a secondary sixth winding, a third W-phase upper bridge driving power circuit, a third U-phase upper bridge driving power circuit and a third V-phase upper bridge driving power circuit;

the homonymous end of the primary side input third winding is connected with the first output end of the forward control circuit, and the heteronymous end of the primary side input third winding is connected with the second output end of the forward control circuit;

the third W-phase upper bridge driving power supply circuit comprises a twenty-first electrolytic capacitor, a twenty-second electrolytic capacitor, a twenty-fifth diode, a twenty-sixth diode, a twenty-seventh diode and a twentieth capacitor, wherein a second end of the twentieth capacitor and a cathode of the twenty-seventh diode are connected with the same-name end of the primary third winding, a first end of the twentieth capacitor is connected with an anode of the twenty-fifth diode and a cathode of the twenty-sixth diode, a cathode of the twenty-fifth diode is connected with an anode of the twenty-first electrolytic capacitor, an anode of the twenty-sixth diode is connected with a cathode of the twenty-first electrolytic capacitor, an anode of the twenty-second electrolytic capacitor and a different-name end of the primary third winding, and a cathode of the twenty-second electrolytic capacitor is connected with an anode of the twenty-seventh diode;

the third U-phase upper bridge driving power supply circuit comprises a twenty-first capacitor, a twenty-eighth diode, a twenty-ninth diode, a thirtieth diode, a twenty-third electrolytic capacitor and a twenty-fourth electrolytic capacitor; a first end of the twenty-first capacitor and a cathode of the thirty-third diode are connected with a dotted terminal of the secondary fifth winding, a second end of the twenty-first capacitor is connected with a cathode of the twenty-eighth diode and an anode of the twenty-ninth diode, an anode of the twenty-eighth diode, a cathode of the twenty-third electrolytic capacitor and an anode of the twenty-fourth electrolytic capacitor are connected with a dotted terminal of the secondary fifth winding, a cathode of the twenty-ninth diode is connected with an anode of the twenty-third electrolytic capacitor, and an anode of the thirty-fourth diode is connected with a cathode of the twenty-fourth electrolytic capacitor;

the third V-phase upper bridge driving power supply circuit comprises a twenty-second capacitor, a thirty-first diode, a thirty-second diode, a thirty-third diode, a twenty-fifth electrolytic capacitor and a twenty-sixth electrolytic capacitor; a first end of the twenty-second capacitor and a cathode of the thirty-third diode are connected with a dotted terminal of the secondary sixth winding, a second end of the twenty-second capacitor is connected with a cathode of the thirty-first diode and an anode of the thirty-second diode, an anode of the thirty-first diode, a cathode of the twenty-fifth electrolytic capacitor and an anode of the twenty-sixth electrolytic capacitor are connected with a dotted terminal of the secondary sixth winding, a cathode of the thirty-second diode is connected with an anode of the twenty-fifth electrolytic capacitor, and an anode of the thirty-third diode is connected with a cathode of the twenty-sixth electrolytic capacitor;

the fourth forward transformer comprises a primary-side input fourth winding, a primary fourth winding, a secondary seventh winding, a secondary eighth winding, a fourth W-phase upper bridge driving power circuit, a fourth U-phase upper bridge driving power circuit and a fourth V-phase upper bridge driving power circuit;

the homonymous end of the primary-side input fourth winding is connected with the first output end of the forward control circuit, and the heteronymous end of the primary-side input fourth winding is connected with the second output end of the forward control circuit;

the fourth W-phase upper bridge driving power supply circuit comprises a twenty-seventh electrolytic capacitor, a twenty-eighth electrolytic capacitor, a thirty-fourth diode, a thirty-fifth diode, a thirty-sixth diode and a twenty-third capacitor, wherein a second end of the twenty-third capacitor and a cathode of the thirty-sixth diode are connected with a same-name end of the primary fourth winding, a first end of the twenty-third capacitor is connected with an anode of the thirty-fourth diode and a cathode of the thirty-fifth diode, a cathode of the thirty-fourth diode is connected with an anode of the twenty-seventh electrolytic capacitor, an anode of the thirty-fifth diode is connected with a cathode of the twenty-seventh electrolytic capacitor, an anode of the twenty-eighth electrolytic capacitor and a different-name end of the primary fourth winding, and a cathode of the twenty-eighth electrolytic capacitor is connected with an anode of the thirty-sixth diode;

the fourth U-phase upper bridge driving power supply circuit comprises a twenty-fourth capacitor, a thirty-seventh diode, a thirty-eighth diode, a thirty-ninth diode, a twenty-ninth electrolytic capacitor and a thirty-ninth electrolytic capacitor; a first end of the twenty-fourth capacitor and a cathode of the thirty-ninth diode are connected with the dotted terminal of the secondary seventh winding, a second end of the twenty-fourth capacitor is connected with a cathode of the thirty-seventh diode and an anode of the thirty-eighth diode, an anode of the thirty-seventh diode, a cathode of the twenty-ninth electrolytic capacitor and an anode of the thirty-eighth electrolytic capacitor are connected with the dotted terminal of the secondary seventh winding, a cathode of the thirty-eighth diode is connected with an anode of the twenty-ninth electrolytic capacitor, and an anode of the thirty-ninth diode is connected with a cathode of the thirty-seventh electrolytic capacitor;

the fourth V-phase upper bridge driving power supply circuit comprises a twenty-fifth capacitor, a fortieth diode, a forty-second diode, a thirty-first electrolytic capacitor and a thirty-second electrolytic capacitor; the first end of the twenty-fifth capacitor and the cathode of the forty-second diode are connected with the dotted terminal of the secondary eighth winding, the second end of the twenty-fifth capacitor is connected with the cathode of the forty-second diode and the anode of the forty-second diode, the cathode of the thirty-first electrolytic capacitor and the anode of the thirty-second electrolytic capacitor are connected with the dotted terminal of the secondary eighth winding, the cathode of the forty-second diode is connected with the anode of the thirty-first electrolytic capacitor, and the anode of the forty-second diode is connected with the cathode of the thirty-second electrolytic capacitor.