CN106740152A - A kind of electric automobile uses the vehicle-mounted integrated form charge-discharge circuit of shunting tap - Google Patents

Abstract

The invention provides a vehicle-mounted integrated charging and discharging circuit using taps for electric vehicles, which utilizes existing circuits and auxiliary devices inside the electric vehicle, including stator windings of two motors, inverter circuits of two motors, cooling, mechanical devices, etc. Then add the taps of the stator winding, and change the inductance value in the circuit through the switch control of the contactor to adapt to the charging power; wherein, the stator winding of the motor on the rectification side containing the taps and the fifth group of contactors constitute a variable The inductance combination 1 consists of a variable inductance combination 2 composed of the stator winding of the direct-to-direct conversion side motor with taps and the sixth group of contactors; in addition, a contactor for switching charge and discharge needs to be added; the circuit The integration degree of the internal circuit of the electric vehicle is improved, the cost is reduced, the available internal space is increased, and the comfort of the user is increased.

Description

A vehicle-mounted integrated charging and discharging circuit using taps for electric vehicles

technical field

The invention relates to a vehicle-mounted integrated charging and discharging circuit using taps for electric vehicles. The circuit is used to charge the energy storage equipment of the electric vehicle, and at the same time, the energy storage equipment provides power for the motor.

Background technique

The charger in the electric vehicle is one of the key components for fast and flexible charging of the electric vehicle battery and to promote the technological progress and market promotion of electric vehicles. Its cost, volume, weight and performance have become the key and restrictive factors for its development.

According to the relationship between the charging circuit and the motor drive circuit, the current in-vehicle chargers are divided into independent type and integrated type. The independent charging device is a completely independent charging device, which is input by an external AC 3-phase or single-phase power supply, and the charger converts it into a DC that meets the battery charging standard to complete the charging function; On the basis of the inverter, additional contactors and power electronic modules (such as switching devices, drive circuits, processors and their peripheral circuits, etc.) are added to realize the charging function, which partially reduces the cost, volume and weight. Similar to a stand-alone charging unit.

Some vehicle-mounted integrated charging and discharging circuits use an external inductance coil to form a charging and discharging circuit. In order to improve the integration of the circuit, the stator winding of the motor can be used as the inductance of the charging circuit, but the inductance of the winding is large, which is not conducive to use. Need to consider some ways to reduce the inductance value, in order to adapt to the needs of charging.

Contents of the invention

The purpose of the present invention is to provide a vehicle-mounted integrated charging and discharging circuit using taps for electric vehicles, which uses stator windings to improve the integration of the vehicle-mounted circuits, and at the same time solves the problem of the adaptability of the winding inductance to the charging power.

In order to achieve the above purpose, an embodiment of the present invention provides a vehicle-mounted integrated charging and discharging circuit using a tap for an electric vehicle, including: ① the stator winding of the motor on the rectification side containing the tap and the inverter circuit connected to it; ② including the tap The stator winding of the direct-to-direct conversion side motor connected to the tap and the inverter circuit connected to it; ③The decoupling capacitor between the motor inverter on the rectification side and the motor inverter on the direct-to-direct conversion side; ④Charging interface, such as three-phase AC charging interface, single-phase AC charging interface; ⑤ in-vehicle energy storage equipment, such as: super capacitor, battery, flywheel energy storage, air compression energy storage, etc.

Wherein, the motor on the rectification side refers to a motor connected to a three-phase bridge used for rectification during charging; the motor on the DC side refers to a three-phase bridge connected to DC/DC when charging. The motors; these two motors are not limited to drive motors, but can also be air-conditioning compressors, or other motors on electric vehicles that meet the circuit conditions.

Wherein, the vehicle-mounted charging power adaptive charging and discharging circuit also includes: a first group of contactors, connected to the stator winding of the motor on the rectification side, for cutting off or conducting the AC power interface; a second group of contactors , connected to the rectification side motor stator winding, used to cut off or conduct the star connection of the drive motor stator winding; the third group of contactors, connected to the positive pole of the energy storage device, used to cut off or conduct the energy storage device The connection with the motor inverter is to switch the circuit connection between charging and discharging; the fourth set of contactors is connected to the neutral point of the motor winding on the direct-to-direct conversion side, and is used to realize the three-way parallel Buck during charging. conversion or three-way interleaved Buck conversion; the fifth group of contactors is connected to the tap of the stator winding of the motor on the rectification side, and is used to adjust the inductance value of the rectification side circuit during charging; the sixth group of contactors is connected to the rectification side. The tap of the stator winding of the motor on the DC conversion side is used to adjust the inductance value of the DC conversion side circuit during charging; the decoupling capacitor is connected to the motor inverter on the rectification side and the motor inverter on the DC conversion side Between, used for voltage regulation.

Wherein, the rectifying-side motor stator winding with taps and the fifth set of contactors form a variable inductance combination 1, and the inductance value can be changed through the switch control of the contactors to adapt to different charging powers. Similarly, the stator winding of the direct-to-direct conversion motor with taps and the sixth group of contactors form a variable inductance combination 2 .

Wherein, the switch state of the contactor in the variable inductance combination 1 depends on the charging power setting value of the user or designer; when high power is required, the variable The total inductance value of the inductance combination 1 decreases; otherwise, it increases. The switch state of the contactor in the variable inductance combination 2 depends on the charging power setting value of the user or designer; when high power is required, the variable inductance can be set by setting the switch state of the contactor The total inductance value of combination 2 decreases; otherwise, it increases.

Wherein, the tap of the stator winding of the motor is a fixed tapping tap adapted to the charging power, and may also be a plurality of taps drawn from the stator winding of the motor.

Further, in the embodiment, the variable inductance combination 1 and the motor inverter circuit on the rectification side constitute a step-up rectification circuit, which realizes automatic matching between the inductance coil and power, PWM rectification function, voltage boost function and input Current active power correction function.

Further, in the embodiment, the variable inductance combination 2 and the motor inverter circuit on the direct-to-direct conversion side form a three-way Buck circuit to realize power adaptive direct-to-direct conversion based on three-way parallel Buck circuits.

Further, in the embodiment, the variable inductance combination 1 is connected to the external AC power interface, which includes three rectification-side motor stator windings connected in series in each phase and the inductance coil 1 connected in parallel to the three phases. When the AC power interface is connected to a three-phase AC, the three-phase AC is PWM-rectified through the variable inductance combination 1 and the switching device of the motor inverter on the rectification side.

Further, in the embodiment, the variable inductance combination 1 is connected to the external AC power interface, which includes three rectification-side motor stator windings connected in series in each phase and the inductance coil 1 connected in parallel to the three phases. When the AC power interface is connected to single-phase AC, the single-phase AC is PWM rectified through the corresponding coil in the variable inductance combination 1 and the corresponding switching device in the motor inverter on the rectification side.

Further, in the embodiment, when the electric vehicle is in the driving mode (the electric vehicle is running or the drive motor is running or ready to run), the first, fourth, fifth and sixth groups of contactors are disconnected, and the second, The three groups of contactors are closed, and at this time, the motors are all in the state of being able to be driven (satisfying the normal operation of the air conditioner while the electric vehicle is running); when the electric vehicle is charging, the second and third groups of contactors are disconnected, and the first 1. The four groups of contactors are closed, and the switching states of the fifth group of contactors and the sixth group of contactors are set according to the charging power demand of the user.

The electric vehicle of the embodiment of the present invention adopts a vehicle-mounted integrated charge-discharge circuit with taps, and proposes a vehicle-mounted integrated charge-discharge circuit with taps, that is, on the basis of the current vehicle-mounted integrated charging circuit, the motor stator The winding is used as an inductance, and then the stator winding is added to divide the taps. Through the switch control of the contactor, the inductance value in the circuit can be changed, which can meet the charging requirements of the energy storage device. At the same time, the integration of the internal circuit of the electric vehicle is improved, and the cost is reduced. The available internal space is increased, and the user's comfort is increased.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings on the premise of not paying creative efforts.

FIG. 1 is a schematic diagram of a vehicle-mounted integrated charging and discharging circuit using taps for an electric vehicle according to an embodiment of the present invention.

FIG. 2 is a three-phase AC charging equivalent circuit of an on-vehicle integrated charging and discharging circuit using taps for an electric vehicle according to an embodiment of the present invention.

FIG. 3 is a single-phase AC charging equivalent circuit of the vehicle-mounted integrated charging and discharging circuit using taps for an electric vehicle according to an embodiment of the present invention.

FIG. 4 is a discharge equivalent circuit of an on-vehicle integrated charging and discharging circuit using taps for an electric vehicle according to an embodiment of the present invention.

Fig. 5 is a schematic diagram of a fixed tap of a motor stator winding.

Fig. 6 is a schematic diagram of multiple taps of the motor stator winding.

The list of parts listed in the attached drawings is as follows:

01: Single-phase power interface; 02: Three-phase power interface;

11: The first group of contactors; 12: The second group of contactors;

13: The third group of contactors; 14: The fourth group of contactors;

15: The fifth group of contactors; 16: The sixth group of contactors;

21: rectifier side motor; 22: direct-to-direct conversion side motor;

31: coupling capacitance;

41: Rectification side motor inverter circuit; 42: Rectification side motor inverter circuit;

51: energy storage equipment;

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The present invention is mainly composed of shared circuits, auxiliary devices, additional devices, and contactors:

Shared circuit: (1) Motor inverter on the rectification side, including switching devices (IGBT or 2OSFET or GTO or thyristor, etc.) and its modules, trigger circuit, sampling circuit, digital processor and its peripheral circuits, required different voltages (2) The motor inverter on the direct-to-direct conversion side (same as the motor inverter on the rectification side); (3) The motor stator winding on the rectification side and the stator winding on the direct-to-direct conversion side.

Auxiliary devices: (1) Machinery and heat dissipation devices, such as car frames for mechanical support, heat dissipation and cooling devices, and screws for fixing; (2) Stabilizing capacitors connected in parallel between the two inverters.

Additional components: (1) stator winding taps of the motor on the rectification side; (2) taps of the stator windings of the DC-to-DC conversion side.

Contactors: Contactors are mainly used for circuit switching between charging and driving states of electric vehicles.

FIG. 1 is a schematic diagram of a charging and discharging circuit for vehicle-mounted charging power self-adaptation of an electric vehicle according to an embodiment of the present invention. As shown in Figure 1, the charging and discharging circuit in the electric vehicle of the present embodiment includes: ① a capacitor C1 between the motor inverter (41) on the rectification side and the motor inverter (42) on the DC side (31), used for voltage stabilization; ②The first group of contactors (11), connected to the AC power interface (01/02) and the stator winding of the rectifier side motor (21), are used to cut off or conduct all ③ the second group of contactors (12), connected to the stator winding of the rectifying side motor (21), used to cut off or conduct the star connection of the rectifying side motor (21) stator winding; ④ The third group of contactors (13), connected to the positive pole of the energy storage device (51), are used to cut off or conduct the connection between the energy storage device (51) and the motor inverter (42) on the direct-to-direct conversion side, and switch charging It is connected with the circuit in the discharge state; ⑤ the fourth group of contactors (14), connected to the neutral point of the stator winding (22) of the motor on the direct-to-direct conversion side, are used to switch the charging and discharging states, and realize the three-way contactor during charging. Parallel Buck conversion or three-way interleaved Buck conversion; 6. The fifth group of contactors (15), connected to the taps of the stator windings (21) of the rectifying side motor, used to adjust the inductance value of the rectifying side circuit when charging; 7. Six groups of contactors (16) are connected to taps of the stator winding (22) of the motor on the direct-to-direct conversion side, and are used to adjust the inductance value of the direct-to-direct conversion side circuit during charging.

In this embodiment, the existing components of the electric vehicle: ① The motor inverter (41) on the rectification side is connected to the stator winding (21) of the motor on the rectification side, and is used for the energy transfer of the energy storage device (51) to the The motor on the rectification side, or the voltage used for the AC power interface (01/02) is converted into a DC voltage to perform functions such as rectification and power factor correction; ②The motor inverter circuit (42) on the DC conversion side is connected to The stator winding (22) of the motor on the direct-to-direct conversion side is used to transfer the energy of the energy storage device (51) to the rectification side motor (22), or to control the current when charging the energy storage device , voltage, the energy of the voltage stabilizing capacitor (31) side is transferred to the energy storage device; ③ the stator winding (21) of the motor on the rectification side is connected to the motor inverter (41) on the rectification side, and is used for the motor ( 21) Generate electromagnetic torque to drive the electric vehicle to travel, or to boost the voltage during rectification; ④The motor stator winding (22) on the direct-to-direct conversion side is connected to the motor inverter (42) on the direct-to-direct conversion side, used for The direct-to-direct conversion side motor generates electromagnetic torque to drive the electric vehicle, or to reduce current ripple during charging.

Wherein, the motor on the rectification side refers to the motor connected to the three-phase bridge used for rectification during charging; the motor on the direct-to-direct conversion side refers to the three-phase bridge used for direct-to-direct conversion (DC/DC) when charging The connected motors; these two motors are not limited to drive motors, but can also be air-conditioning compressors, or other motors on electric vehicles that meet the circuit conditions.

Wherein, the rectifying-side motor stator winding with taps and the fifth set of contactors form a variable inductance combination 1, and the inductance value can be changed through the switch control of the contactors to adapt to different charging powers. Similarly, the stator winding of the direct-to-direct conversion motor with taps and the sixth group of contactors form a variable inductance combination 2 .

Wherein, the switch state of the contactor in the variable inductance combination 1 depends on the charging power setting value of the user or designer; when high power is required, the variable The total inductance value of the inductance combination 1 decreases; otherwise, it increases. The switch state of the contactor in the variable inductance combination 2 depends on the charging power setting value of the user or designer; when high power is required, the variable inductance can be set by setting the switch state of the contactor The total inductance value of combination 2 decreases; otherwise, it increases.

Wherein, the tap of the stator winding of the motor is a fixed tapping tap (FIG. 5) adapted to the charging power, or a plurality of taps drawn from the stator winding of the motor (FIG. 6).

In this embodiment, the variable inductance combination 1 is connected to an external AC power supply through the power interface. When the AC power interface is connected to three-phase AC power, the three-phase AC power is PWM rectified through the circuit of the variable inductance combination 1 and the motor inverter (41) on the rectification side; When the single-phase alternating current is input, the single-phase alternating current is PWM rectified through the corresponding coil in the variable inductance combination 1 and the two bridge arm circuits corresponding to the motor inverter (41) on the rectifying side.

When charging, if the power interface is connected to the three-phase AC, the three-phase inverter bridge of the motor inverter (41) on the rectification side will all participate in the work to realize the function of PWM rectification, and at the same time realize the active power factor correction of the input current on the grid side The function and the boost function of the output voltage of the inverter bridge. The basic idea of PWM is to represent the average value of the sinusoidal low-frequency modulation signal within a switching cycle with a pulse width of equal amplitude, and to compare the rectification side motor inverter in the topology ( The six switching devices in 41) perform PWM control. At the same time, due to the energy storage and filtering functions of the variable inductance combination 1, the function of rectifying AC power into DC power can be realized. The voltage on the DC output side is boosted compared with the line voltage on the AC input side. Ability to simultaneously realize the power factor correction function that the current and voltage of each phase of the three-phase input basically achieve the same frequency and phase.

If the power interface is connected to single-phase AC, two phases in the three-phase inverter bridge of the motor inverter (41) on the rectification side will participate in the work, and the corresponding two circuits in the variable inductance combination 1 connected to it will participate in the work. At this time, the PWM rectification and boosting functions are completed for the single-phase H-bridge, and the power factor correction function of the input current can also be realized at the same time.

During charging, among the six switching devices and six anti-parallel diodes of the motor inverter (42) on the direct-to-direct conversion side, only three switching devices of the upper bridge arm are used, and three anti-parallel diodes of the lower bridge arm are used. , while the three antiparallel diodes of the upper bridge arm and the three switching devices of the lower bridge arm are in a non-conducting state. One of the switching devices of the upper bridge arm and the corresponding anti-parallel diodes of the lower bridge arm form a single-tube Buck circuit, and then three switching devices of the upper bridge arm and the corresponding three anti-parallel diodes of the lower bridge arm form a three-way circuit. In the single-tube Buck circuit, the three-way Buck circuit either realizes parallel Buck conversion in which three switching devices are turned on and turned off at the same time, or realizes interleaved parallel Buck conversion. The Buck circuit of each channel is a common single-tube Buck step-down circuit.

The working mode of the electric vehicle on-board charger of the above-mentioned embodiment is as follows:

1. When the electric vehicle is in the driving mode (the electric vehicle is running or the drive motor is running or waiting to run), the contactors 11, 14, 15, and 16 are disconnected, and the contactors 12 and 13 are closed. In the driven state (satisfying the normal operation of the air conditioner while the electric vehicle is running), the equivalent circuit is shown in Figure 4.

2. When the electric vehicle is in charging mode:

A. When the AC charging interface is connected to three-phase AC power, the contactors 12 and 13 are disconnected, and the contactors 11 and 14 are closed. The states of the contactors 15 and 16 are set according to the user's charging power requirements. The equivalent circuit is shown in FIG. 2 . The three-phase alternating current 02 is connected as shown in Figure 2, and the three-phase alternating current is PWM rectified through the variable inductance combination 1 and the switching device of the motor inverter circuit 41 on the rectification side, so that the input side current power factor and The requirement of harmonics and the increase of the DC side voltage, after passing through the intermediate capacitor 31, and then through the switching device and the variable inductance combination 2 of the motor inverter circuit 42 on the direct-to-direct conversion side, realize the three-way parallel Buck function, Or realize the three-way interleaved Buck function to achieve the purpose of stepping down and stabilizing the current, so as to meet the voltage and current requirements for charging the battery.

B. When the AC charging interface is connected to single-phase AC power, the contactors 12 and 13 are disconnected, and the contactors 11 and 14 are closed. According to the charging power requirement set by the user, the states of the contactors 15 and 16 are set, and the equivalent circuit is shown in FIG. 3 . The single-phase alternating current 01 is connected as shown in FIG. 3 , and the single-phase alternating current performs PWM through two of the windings of the variable inductance combination 1 and the bridge arm corresponding to the winding of the rectifying side motor inverter circuit 41 Rectification can realize the requirements of the input side current power factor and harmonics and the improvement of the DC side voltage. After passing through the intermediate capacitor 31, it passes through the switching device of the motor inverter circuit 42 on the direct-to-direct conversion side and the variable Inductor combination 2 realizes the three-way parallel Buck function, or realizes the three-way interleaved Buck function to achieve the purpose of stepping down and stabilizing the current, so as to meet the voltage and current requirements for charging the battery.

In order to realize the vehicle-mounted integrated charging and discharging circuit using taps for electric vehicles, the embodiment of the present invention proposes a topology structure with taps, which utilizes existing parts in electric vehicles (mainly switching devices in power electronic circuits) , passive components, electronic circuits, such as the stator winding of the motor (21, 22), and the power switch tube of the motor inverter (41, 42) and its drive circuit and other circuits, etc., in addition to cooling system/device, mechanical parts, etc.), and then add two motor taps and corresponding contactors to form two sets of variable inductance combinations, so that the motor stator winding can be used for charging electric vehicles, which improves the internal circuit of electric vehicles. The degree of integration reduces the cost, increases the available internal space, and increases the comfort of users.

In the present invention, specific examples have been applied to explain the principles and implementation methods of the present invention, and the descriptions of the above examples are only used to help understand the method of the present invention and its core idea; meanwhile, for those of ordinary skill in the art, according to this The idea of the invention will have changes in the specific implementation and scope of application. To sum up, the contents of this specification should not be construed as limiting the present invention.

Claims (8)

1. A vehicle-mounted integrated charge-discharge circuit using a tap for an electric vehicle is characterized in that the vehicle-mounted integrated charge-discharge circuit for an electric vehicle that uses a tap comprises: a rectifying side motor stator winding that contains a tap The variable inductance combination 1 formed with the fifth group of contactors, the variable inductance combination 2 composed of the stator winding of the direct-to-direct conversion side motor with taps and the sixth group of contactors, the two motor inverters The circuit and the corresponding control circuit, the coupling capacitor between the inverter circuits of the two motors, the energy storage device, and the AC charging interface; Wherein, the tap of the stator winding of the motor is a fixed tapping tap adapted to the charging power, or it may be a plurality of taps drawn from the stator winding of the motor. Wherein, the motor on the rectification side refers to a motor connected to a three-phase bridge used for rectification during charging; the motor on the DC side refers to a three-phase bridge connected to DC/DC when charging. The motors; these two motors are not limited to drive motors, but can also be air-conditioning compressors, or other motors on electric vehicles that meet the circuit conditions; Wherein, the self-adaptive charging and discharging circuit of the vehicle-mounted charging power of the electric vehicle also includes: The first group of contactors is connected to the stator winding of the motor on the rectification side, and is used to cut off or turn on the AC power interface; The second group of contactors is connected to the stator winding of the motor on the rectification side, and is used to cut off or conduct the star connection of the stator winding of the drive motor; The third group of contactors is connected to the positive pole of the energy storage device, and is used to cut off or conduct the connection between the energy storage device and the motor inverter, and switch the circuit connection between charging and discharging states; The fourth group of contactors is connected to the neutral point of the motor winding on the direct-to-direct conversion side, and is used to realize three-way parallel Buck conversion or three-way interleaved Buck conversion during charging; The fifth group of contactors is connected to the taps of the stator winding of the motor on the rectification side, and is used to adjust the inductance value of the rectification side circuit during charging; The sixth group of contactors is connected to the taps of the stator winding of the motor on the direct-to-direct conversion side, and is used to adjust the inductance value of the direct-to-direct conversion side circuit during charging. 2. The vehicle-mounted integrated charging and discharging circuit using taps for electric vehicles according to claim 1, characterized in that the state of the contactor switch in the variable inductance combination 1 depends on the user or designer's Charging power setting value; when high power is required, the total inductance value of the variable inductance combination 1 is reduced by setting the switch state of the contactor; otherwise, it is increased. 3. The vehicle-mounted integrated charging and discharging circuit using taps for electric vehicles according to claim 1, characterized in that the state of the contactor switch in the variable inductance combination 2 depends on the user or designer's Charging power setting value; when high power is required, the total inductance value of the variable inductance combination 2 is reduced by setting the switch state of the contactor; otherwise, it is increased. 4. The electric vehicle according to claim 1 adopts the vehicle-mounted integrated charging and discharging circuit with taps, wherein, when the electric vehicle is in the running mode (the electric vehicle is running or the driving motor is in operation or waiting for operation), the The first, fourth, fifth, and sixth groups of contactors are disconnected, and the second and third groups of contactors are closed. At this time, the motors are all in the state of being able to be driven (satisfying the normal operation of the air conditioner while the electric vehicle is running); the electric vehicle When charging, the second and third groups of contactors are disconnected, the first and fourth groups of contactors are closed, and the fifth group of contactors is set to be in contact with the sixth group according to the charging power demand of the user. switch state of the device. 5. The electric vehicle according to claim 1 adopts a vehicle-mounted integrated charging and discharging circuit with taps, wherein the variable inductance combination 1 and the rectifying side motor inverter circuit jointly realize the PWM rectification function, Voltage boost function and input current active power factor correction function. 6. The electric vehicle according to claim 1 adopts a vehicle-mounted integrated charging and discharging circuit with taps, wherein the variable inductance combination 2 and the motor inverter circuit on the direct-to-direct conversion side jointly realize a three-way Parallel Buck conversion or three-way interleaved Buck conversion. 7. The electric vehicle according to claim 5 adopts a vehicle-mounted integrated charging and discharging circuit with taps, wherein the variable inductance combination 1 is connected to an external AC power supply, which includes: three connected in series respectively in each The stator windings of the rectifier-side motor in the phase are respectively connected in parallel with the inductance coils of the three-phase stator windings, and the corresponding contactors; when the AC power supply is a three-phase input, the three-phase AC power passes through the variable voltage The induction combination 1 and the motor inverter circuit on the rectification side perform PWM rectification. 8. The electric vehicle according to claim 5 adopts a vehicle-mounted integrated charging and discharging circuit with taps, wherein the variable inductance combination 1 is connected to an external AC power supply, which includes: three connected in series respectively The stator windings of the motor on the rectification side in the phase are respectively connected in parallel with the inductance coils of the three-phase stator windings, and the corresponding contactors; when the AC power supply is single-phase input, the single-phase AC power passes through the variable voltage Two groups of the induction combination 1 and corresponding two circuits in the motor inverter circuit on the rectification side perform PWM rectification.