CN111347924B

CN111347924B - Motor control circuit, vehicle, heating method and charging and discharging method

Info

Publication number: CN111347924B
Application number: CN201811574159.9A
Authority: CN
Inventors: 潘华; 张宇昕; 姜龙; 杨宁; 其他发明人请求不公开姓名
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2018-12-21
Filing date: 2018-12-21
Publication date: 2022-09-09
Anticipated expiration: 2038-12-21
Also published as: CN111347924A

Abstract

The application provides a motor control circuit, a vehicle, a heating method and a charging and discharging method of the vehicle, wherein the motor control circuit comprises a boosting module, a three-phase inverter, a three-phase alternating current motor, a first switch module and a control module, N lines are led out from the three-phase alternating current motor to further form a multiplexing circuit with a power battery, the boosting module and the three-phase inverter, the multiplexing circuit can realize boosting charging, voltage reduction charging and direct charging of an external power module, can also realize boosting discharging, voltage reduction discharging and direct discharging of the external power module by the power battery in the vehicle, can also realize power taking from the external power module or the power battery, and controls the boosting module, the three-phase inverter and the three-phase alternating current motor to heat a heat exchange medium flowing through at least one of the boosting module, the three-phase inverter and the three-phase alternating current motor, and an external boosting or voltage-reducing circuit or a heating circuit is not required to be additionally arranged, so that the cost of an additional circuit is reduced.

Description

Motor control circuit, vehicle, heating method and charging and discharging method

Technical Field

The application relates to the technical field of vehicles, in particular to a motor control circuit, a vehicle, a heating method and a charging and discharging method.

Background

In recent years, new energy vehicles are developed vigorously, power batteries based on lithium ions are widely used, and due to the inherent characteristics of the batteries, the charge and discharge capacity of the power batteries is greatly reduced at low temperature, which affects the use of electric vehicles in cold regions.

In order to solve the problem, in the prior art, a technical scheme is that a battery management system acquires and sends the temperature of a power battery unit, if the temperature is lower than a preset temperature threshold value, a vehicle controller commands an engine controller to control an engine to rotate at a constant speed at a certain rotating speed through CAN communication, the engine drives a generator to rotate, and the power battery unit is rapidly charged and discharged through the generator to achieve the purpose of preheating a battery pack.

Another technical scheme in the prior art is that when the ambient temperature is low and the power battery needs to be heated, the heat exchange medium is pumped out by the water pump from the refrigerant liquid tank and is heated by the PTC heater and then is sent into the liquid cooling plate of the power battery, so that the temperature of the liquid cooling plate of the power battery is raised, and then the liquid cooling plate of the power battery heats the power battery, thereby improving the working performance of the power battery under the cold condition. In the technical scheme, a PTC heater is needed, so that the cost is increased, and if the PTC heater is damaged, the secondary cost is increased.

In addition, along with the development and rapid popularization of electric vehicles, the charging technology of power batteries of electric vehicles becomes more and more important, the charging technology needs to meet the requirements of different users, the current boost charging circuit is generally formed by adding a bidirectional boost-buck DC/DC bridge circuit to a positive bus and a negative bus between a charging pile and the power batteries, and the current boost charging circuit needs to be separately added with the DC/DC bridge circuit, a corresponding control and detection circuit and the like, so that the product cost is increased.

In summary, in the prior art, when the power battery is heated in a low temperature state, the heating efficiency of the battery is low due to the heating of the engine, and the cost is increased due to the heating of the PTC heater.

Disclosure of Invention

The application aims to provide a motor control circuit, a vehicle, a heating method and a charging and discharging method, and aims to solve the problems that in the prior art, when a power battery is charged and a boosting charging mode is adopted, a boosting circuit needs to be added, heating is conducted on a to-be-heated part, and a PTC heater needs to be added, so that the size and the cost of the whole device are increased.

This application is so realized, this application first aspect provides a motor control circuit, motor control circuit is including boost module, first switch module, three-phase inverter, three-phase alternating current motor and second switch module, motor control circuit passes through boost module is connected with external power module, motor control circuit passes through second switch module is connected with power battery, boost module passes through first switch module is connected three-phase inverter with second switch module, three-phase inverter connects three-phase alternating current motor with between the second switch module, boost module still connects the mid point that three-phase coil of three-phase alternating current motor connects, control module respectively with boost module first switch module three-phase inverter three-phase alternating current motor, The second switch module is connected with the power battery.

A second aspect of the present application provides a heating method of a vehicle, based on the motor control circuit of the first aspect, the heating method including:

when the control module acquires that the part to be heated needs to be heated, the first switch module, the second switch module, the boosting module and the three-phase inverter are controlled to alternately perform the charging process of the boosting module and a three-phase coil of the three-phase alternating current motor and the discharging process of the boosting module and the three-phase coil of the three-phase alternating current motor by the power battery, so that the boosting module, the three-phase inverter and the three-phase alternating current motor heat a heat exchange medium flowing through at least one of the boosting module, the three-phase inverter and the three-phase alternating current motor.

A third aspect of the present application provides a heating method of a vehicle, based on the motor control circuit of the first aspect, the heating method including:

when the control module is connected with an external power supply module and a part to be heated needs to be heated, the external power supply module controls the first switch module, the second switch module, the boosting module and the three-phase inverter to alternately perform a charging process of the boosting module and a three-phase coil of the three-phase alternating current motor and a discharging process of the boosting module and the three-phase coil of the three-phase alternating current motor, so that the boosting module, the three-phase inverter and the three-phase alternating current motor heat a heat exchange medium flowing through at least one of the boosting module, the three-phase inverter and the three-phase alternating current motor.

A fourth aspect of the present application provides a charging method for a vehicle, based on the motor control circuit of the first aspect, the charging method including:

when the control module acquires that the highest output voltage of the external power supply module is lower than the voltage of the power battery, the control module controls the first switch module, the second switch module, the boosting module and the three-phase inverter to enable the external power supply module to alternately perform the charging process of the boosting module and the three-phase coil of the three-phase alternating current motor and the discharging process of the external power supply module, the boosting module and the three-phase coil of the three-phase alternating current motor on the power battery, so that the charging voltage of the external power supply module is boosted to exceed the voltage of the power battery and then the power battery is charged.

A fifth aspect of the present application provides a discharging method for a vehicle, based on the motor control circuit of the first aspect, when the motor control circuit is connected to the power module, the discharging method comprising:

acquiring the voltage of the electricity utilization module and the voltage of the power battery, and selecting a discharging mode according to the voltage of the electricity utilization module and the voltage of the power battery, wherein the discharging mode comprises boosting discharging, reducing discharging and direct discharging;

and controlling the first switch module, the second switch module, the three-phase inverter and the boost module to enable the power battery to output direct current, and enabling the power battery to discharge the power utilization module according to the selected charging mode.

A sixth aspect of the present application provides a vehicle, further comprising the motor control circuit of the first aspect, the vehicle further comprising a driving module and a heat exchange medium pipeline, the driving module being connected to the control module;

the control module controls the driving module to drive the heat exchange medium in the heat exchange medium pipeline to flow through at least one of the energy storage module, the three-phase inverter and the three-phase alternating current motor.

The application provides a motor control circuit, a vehicle, a heating method and a charging and discharging method, wherein the power battery motor control circuit comprises a boosting module, a three-phase inverter, a three-phase alternating current motor, a first switch module and a control module, N lines are led out from the three-phase alternating current motor, and then a multiplexing circuit is formed by the boosting module, the boosting module and the three-phase inverter, the multiplexing circuit can be used for realizing boosting charging, voltage reduction charging and direct charging of an external power battery in the vehicle by an external power module, and can also be used for realizing boosting charging, voltage reduction charging and direct charging of the external power module by the power battery in the vehicle without additionally adding an external boosting or voltage reduction circuit, so that the cost of an additional circuit is reduced, in addition, the multiplexing circuit can be used for realizing power taking from the external power module or the power battery, and controlling the boosting module, voltage reduction module and charging and discharging method, Three-phase inverter and three-phase alternating current motor heat the heat transfer medium who flows through at least one in module, three-phase inverter and the three-phase alternating current motor that steps up, when heat transfer medium flows through and treats the heating member, promote the temperature of treating the heating member, need not use the engine or increase motor control circuit just can realize promoting the temperature of treating the heating member, and heating efficiency is high, and the temperature of treating the heating member risees sooner.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic structural diagram of a motor control circuit according to an embodiment of the present disclosure;

fig. 2 is another schematic structural diagram of a motor control circuit according to an embodiment of the present disclosure;

fig. 3 is another schematic structural diagram of a motor control circuit according to an embodiment of the present disclosure;

FIG. 4 is a circuit diagram of the motor control circuit provided in FIG. 3 according to one embodiment of the present application;

fig. 5 is another schematic structural diagram of a motor control circuit according to an embodiment of the present application;

FIG. 6 is a circuit diagram of the motor control circuit provided in FIG. 5 according to one embodiment of the present application;

fig. 7 is a current path diagram of a motor control circuit in a first tank state in a heating method of a vehicle according to a second embodiment of the present application;

fig. 8 is a current path diagram of a motor control circuit in a second tank circuit state in a heating method of a vehicle according to a second embodiment of the present application;

fig. 9 is a current path diagram of a motor control circuit in a first freewheel loop state in a heating method for a vehicle according to a second embodiment of the present application;

fig. 10 is a current path diagram of a motor control circuit in a second freewheel loop state in a heating method for a vehicle according to a second embodiment of the present application;

fig. 11 is a current path diagram of a motor control circuit in a third freewheel loop state in a heating method for a vehicle according to a second embodiment of the present application;

fig. 12 is a current path diagram of a motor control circuit in a fourth freewheel loop state in a heating method for a vehicle according to a second embodiment of the present application;

fig. 13 is a current path diagram of a motor control circuit in a third tank state in a heating method of a vehicle according to the second embodiment of the present application;

fig. 14 is a current path diagram of a motor control circuit in a fourth tank state in a heating method of a vehicle according to the second embodiment of the present application;

fig. 15 is a current path diagram of a motor control circuit in a first charging loop state in a heating method of a vehicle according to a third embodiment of the present application;

fig. 16 is a current path diagram of a motor control circuit in a second charging loop state in a heating method of a vehicle according to a third embodiment of the present application;

fig. 17 is a current path diagram of a motor control circuit in a direct charging state in a heating method of a vehicle according to a third embodiment of the present application;

fig. 18 is a current path diagram of a motor control circuit in a first tank state in a discharging method of a vehicle according to a fourth embodiment of the present application;

fig. 19 is a current path diagram of a motor control circuit in a first discharge loop state in a discharge method of a vehicle according to a fourth embodiment of the present application;

fig. 20 is a current path diagram of a motor control circuit in a second discharge loop state in a discharge method of a vehicle according to a fourth embodiment of the present application

FIG. 21 is a schematic structural diagram of a vehicle according to a fifth embodiment of the present disclosure;

fig. 22 is an internal structural schematic diagram of a three-phase alternating-current motor in a vehicle according to a fifth embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

In order to explain the technical means of the present application, the following description will be given by way of specific examples.

In an embodiment of the present application, as shown in fig. 1, the motor control circuit includes a boost module 102, a first switch module 103, a three-phase inverter 104, a three-phase ac motor 105, and a second switch module 106, the motor control circuit is connected to an external power module 101 through the boost module 102, the motor control circuit is connected to a power battery 107 through the second switch module 106, the boost module 102 is connected to the three-phase inverter 104 and the second switch module 106 through the first switch module 103, the three-phase inverter 104 is connected between the three-phase ac motor 105 and the second switch module 106, the boost module 102 is further connected to a midpoint of a connection of three-phase coils of the three-phase ac motor 105, the control module 108 is connected to the boost module 102, the first switching module 103, the three-phase inverter 104, the three-phase ac motor 105, the second switching module 106, and the power battery 107, respectively.

The power supply provided by the external power supply module 101 may be direct current provided by a direct current charging pile, direct current output by a single-phase or three-phase alternating current charging pile after rectification, electric energy generated by a fuel cell, or a power supply form such as direct current rectified by a generator controller and generated by a range extender such as an engine which rotates to drive a generator to generate electricity, or the external power supply module 101 includes an alternating current charging pile, a filter and a rectifier which are connected in sequence, and the rectifier is connected with a first end and a second end of the boosting module 102; the boost module 102 is configured to store electric energy or release current to pump up voltage when being connected to a loop of the power battery 107 or the external power module 101, the boost module 102 may include an energy storage unit and a power switch unit, a control end of the power switch unit is connected to the control module 108, and the power switch unit in the boost module 102 is turned on or off according to a signal output by the control module 108, so that the energy storage unit is connected to different loops to be charged or discharged; the three-phase inverter 104 comprises six power switch units, the power switches can be of transistor, IGBT, MOS tube and other device types, two power switch units form a phase bridge arm, the two phase bridge arms form a three-phase bridge arm, the connection point of the two power switch units in each phase bridge arm is connected with a phase coil in the three-phase alternating current motor 105, the three-phase alternating current motor 105 comprises a three-phase coil, the three-phase coil is connected with a midpoint, the three-phase alternating current motor 105 can be a permanent magnet synchronous motor or an asynchronous motor, the three-phase alternating current motor 105 is of a three-phase four-wire system, namely, a neutral line is led out from the connection midpoint of the three-phase coil, and the neutral line and the boosting module 102 are connected in series to form a connection circuit; the first switch module 103 is used for connecting the boost module 102 with the three-phase inverter 104 to form different charging or discharging circuits; the second switch module 106 is used for connecting or disconnecting the power battery 107 with the motor control circuit; the control module 108 may collect the voltage, current, temperature of the power battery 107 and the phase current of the three-phase ac motor 105, the control module 108 may include a vehicle controller, a control circuit of the motor controller, and a BMS battery manager circuit, which are connected by a CAN line, and different modules in the control module 108 control the turn-on and turn-off of the power switches in the boost module 102 and the three-phase inverter 104 according to the acquired information to realize the turn-on of different current loops.

The embodiment is provided with a first switch module, a second switch module and a boosting module on the basis of the original three-phase alternating current motor and three-phase inverter, when the boosting module is connected with an external power supply module and a power battery is in a low-temperature state, the first switch module and the second switch module are controlled by a control module to realize that the external power supply module, the three-phase inverter and the three-phase alternating current motor form a heating loop to heat a part to be heated, when the power battery can discharge, the power battery, the three-phase inverter and the three-phase alternating current motor form a heating loop to heat the part to be heated, and the first switch module and the second switch module can be controlled to ensure that the external power supply module charges the power battery through the three-phase inverter and the three-phase alternating current motor form a charging loop and the power battery discharges an external power utilization module, the functions of charging and discharging the power battery and heating the part to be heated can be realized only by different combinations of the control switches, and meanwhile, an external charging circuit and a heating circuit are not required to be additionally arranged, so that the cost of an additional circuit is reduced.

In a specific embodiment, it is the same part to wait to heat up the part and power battery, like this, not only in the in-process that forms the circuit loop, power battery can make self temperature rise because of the internal resistance, and, can also be through the produced heat transfer of motor control circuit in this application to power battery, promptly: the motor control circuit in this application both can be used for charging power battery, also can be used for power battery to supply power for three-phase alternating current motor in order to drive the wheel rotation, can also be used to provide the heat source for the power battery that needs the heating.

As an embodiment, as shown in fig. 2, a first end of the boost module 102 is connected to a positive end of the external power module 101 and a first end of the first switch module 103, a second end of the boost module 102 is connected to a negative end of the external power module 101 and a second end of the first switch module 103, a third end of the boost module 102 is connected to a middle point where three-phase coils of the three-phase ac motor 106 are connected, the three-phase coils of the three-phase ac motor 106 are connected to a three-phase arm of the three-phase inverter 104, the first end of the three-phase inverter 104 is connected to a third end of the first switch module 103 and a first end of the second switch module 106, the second end of the three-phase inverter 104 is connected to a fourth end of the first switch module 103 and a second end of the second switch module 106, and the third end and the fourth end of the second switch module 106 are respectively connected to a positive end and a negative end of the power battery 107.

For the first switch module 103, as shown in fig. 3, the first switch module 103 includes a first switch 132 and a fifth switch 131, a first terminal and a second terminal of the fifth switch 131 are a first terminal and a third terminal of the first switch module 103, respectively, and a first terminal and a second terminal of the first switch 132 are a second terminal and a fourth terminal of the first switch module, respectively.

The boost module 102 includes an energy storage unit 111, a seventh power switch unit 112, and an eighth power switch unit 113, a first end of the energy storage unit 111 is a third end of the boost module 102, a second end of the energy storage unit 111 is connected to an output end of the seventh power switch unit 112 and an input end of the eighth power switch unit 113, an input end of the seventh power switch unit 112 is the first end of the boost module 102, and an output end of the eighth power switch unit 113 is the second end of the boost module 102.

The second switch module 106 includes a third switch and a fourth switch, wherein a first end and a second end of the third switch are a first end and a third end of the second switch module 106, respectively, and a first end and a second end of the fourth switch are a second end and a fourth end of the second switch module 106, respectively.

For the three-phase inverter 104, specifically, the three-phase inverter 104 includes a first power switch unit, a second power switch unit, a third power switch unit, a fourth power switch unit, a fifth power switch unit, and a sixth power switch, a control end of each power switch unit is connected to the control module 108, a phase bridge arm formed by every two power switch units, the first power switch unit, the third power switch unit, and the fifth power switch unit are upper bridge power switches of each phase bridge arm, first ends of the first power switch unit, the third power switch unit, and the fifth power switch unit are connected to a second end of the fifth switch, the second power switch unit, the fourth power switch unit, and the sixth power switch unit are lower bridge power switches of each phase bridge arm, second ends of the second power switch unit, the fourth power switch unit, and the sixth power switch unit are connected to a second end of the first switch, a first-phase coil of the three-phase alternating current motor 105 is connected to the second terminal of the first power switching unit and the first terminal of the fourth power switching unit, a second-phase coil of the three-phase alternating current motor 105 is connected to the second terminal of the third power switching unit and the first terminal of the sixth power switching unit, and a third-phase coil of the three-phase alternating current motor 105 is connected to the second terminal of the fifth power switching unit and the first terminal of the second power switching unit.

The first power switch unit and the fourth power switch unit in the three-phase inverter 103 form an a-phase arm, the third power switch unit and the sixth power switch unit form a B-phase arm, the input end of the fifth power switch unit and the second power switch unit form a C-phase arm, the a-phase arm of the three-phase inverter 103 is connected to the first-phase coil of the three-phase ac motor 104, the B-phase arm of the three-phase inverter 103 is connected to the second-phase coil of the three-phase ac motor 104, the C-phase arm of the three-phase inverter 103 is connected to the third-phase coil of the three-phase ac motor 104, and the control method for the three-phase inverter 104 may be any one or a combination of several of the following methods: if any one or any two of A, B, C three-phase bridge arms and three bridge arms can be realized, 7 control voltage rising and reducing charging and heating modes are flexible and simple. Switching of the bridge arms can be beneficial to realizing large, medium and small selection of heating power, for example, for small power boosting, voltage reduction charging and heating, any phase of bridge arm power switch can be selected for control, and three-phase bridge arms can be switched in turn, for example, an A-phase bridge arm works independently first, a first power switch unit and a fourth power switch unit are controlled to heat for a period of time, a B-phase bridge arm works independently, a third power switch unit and a sixth power switch unit are controlled to heat for the same period of time, then a C-phase bridge arm works independently, a fifth power switch unit and a second power switch unit are controlled to heat for the same period of time, and then the A-phase bridge arm works, so that the three-phase inverter 104 and a three-phase coil are electrified and heated in turn, and three-phase heating is more balanced; for example, for medium-power boost charging, buck charging and heating, any two-phase bridge arm power switches can be selected for control, and three-phase bridge arms can be switched in turn, for example, an AB-phase bridge arm works first, a first power switch unit, a fourth power switch unit, a third power switch unit and a sixth power switch unit are controlled to heat for a period of time, then a BC-phase bridge arm works, a third power switch unit, a sixth power switch unit and a second power switch unit are controlled to heat for the same time, then a CA-phase bridge arm works, a fifth power switch unit, a second power switch unit, a first power switch unit and a fourth power switch unit are controlled to heat for the same time, and then the AB-phase bridge arm works, and the steps are repeated to realize that the three-phase inverter 103 and a three-phase coil heat more evenly; for example, for high-power step-up and step-down charging and heating, a three-phase bridge arm power switch can be selected for control, and the three-phase loops are theoretically balanced, so that three-phase currents are balanced, the three-phase inverter 103 and the three-phase coils generate heat, the balanced three-phase currents are basically direct currents, the average values of the three-phase currents are basically consistent, and the three-phase synthesized magnetomotive force in the motor is basically zero due to the symmetry of the three-phase coils, so that the magnetic field of a stator is basically zero, the motor basically generates no torque, and the stress of a transmission system is greatly reduced.

Fig. 4 is a circuit diagram of an example of a motor control circuit provided in an embodiment of the present application, for convenience of description, other electrical devices are omitted in the upper diagram, and only the voltage boost module 102, the first switch module 103, the three-phase inverter 104, the three-phase ac motor 105, and the second switch module 106 are considered, where the voltage boost module 102 includes an inductor, a seventh power switch unit, and an eighth power switch unit, the seventh power switch unit includes a seventh upper bridge arm VT7 and a seventh upper bridge diode VD7, the eighth power switch unit includes an eighth lower bridge arm VT8 and an eighth lower bridge diode VD8, the first switch module 103 includes a switch K5 and a switch K1, the second switch module 106 includes a switch K3 and a switch K4, the first power switch unit in the three-phase inverter 103 includes a first upper bridge arm VT1 and a first upper bridge diode VD1, the second power switch unit includes a second lower bridge arm 2 and a second lower bridge diode VD2, the third power switch unit comprises a third upper bridge arm VT3 and a third upper bridge diode VD3, the fourth power switch unit comprises a fourth lower bridge arm VT4 and a fourth lower bridge diode VD4, the fifth power switch unit comprises a fifth upper bridge arm VT5 and a fifth upper bridge diode VD5, the sixth power switch unit comprises a sixth lower bridge arm VT6 and a sixth lower bridge diode VD6, the three-phase ac motor 104 is a three-phase four-wire system, and can be a permanent magnet synchronous motor or an asynchronous motor, an N line is led out from a connection midpoint of a three-phase coil, and is connected with an inductor L, three-phase coils of the three-phase ac motor 104 are respectively connected with three-phase bridge arms in the three-phase inverter 103, and a specific control method for controlling the power battery charging device to respectively realize heating and charging by the control module 108 refers to the following second embodiment and third embodiment.

In another embodiment, as shown in fig. 5, a first end of the boost module 102 is connected to a positive end of the external power module 101, a second end of the boost module 102 is connected to a negative end of the external power module 101 and a first end of the first switch module 132, a third end of the boost module 102 is connected to a midpoint where three-phase coils of the three-phase ac motor 105 are connected, the three-phase coils of the three-phase ac motor 105 are connected to a three-phase arm of the three-phase inverter 104, the first end of the three-phase inverter 104 is connected to a first end of the second switch module 106, the second end of the three-phase inverter 104 is connected to a second end of the second switch module 106, and a third end and a fourth end of the second switch module 106 are respectively connected to a positive end and a negative end of the power battery 107.

Fig. 6 is a circuit diagram of an example of a motor control circuit provided in an embodiment of the present application, and is different from fig. 4 in that the first switch module only includes a switch K1.

The second embodiment of the present application provides a heating method for a vehicle, based on the motor control circuit provided in the above embodiment, the heating method includes:

when the control module acquires that the to-be-heated component needs to be heated, the control module controls the first switch module, the second switch module, the boosting module and the three-phase inverter, so that the power battery alternately performs the charging process of the three-phase coil of the boosting module and the three-phase alternating current motor and the discharging process of the three-phase coil of the boosting module and the three-phase alternating current motor, and the boosting module, the three-phase inverter and the three-phase alternating current motor heat a heat exchange medium flowing through at least one of the boosting module, the three-phase inverter and the three-phase alternating current motor.

The power battery heating device comprises a power battery, a boosting module, a three-phase inverter and a three-phase alternating current motor, wherein the boosting module is used for boosting a heat transfer medium flowing through at least one of the boosting module, the three-phase inverter and the three-phase alternating current motor, the boosting module is used for boosting the temperature of the power battery, the three-phase inverter is used for driving the three-phase alternating current motor to work, and the battery is heated together when the temperature of the to-be-heated component is lower than the preset temperature.

Because of the inherent characteristics of the battery, the charge and discharge capacity of the power battery 107 is greatly reduced in a low-temperature state, which may affect the use of the new energy vehicle in a cold region, and in order to make the power battery 107 work normally, it is necessary to raise the temperature of the power battery 107 when the temperature of the power battery 107 is too low, therefore, the temperature of the power battery 107 is obtained through the control module 108, the battery manager may be used to obtain the temperature of the power battery 107, the temperature of the power battery 107 is compared with a preset temperature value to determine whether the power battery 107 is in a low-temperature state, when the obtained temperature of the power battery 107 is lower than the preset temperature value, the temperature of the power battery 107 may be raised by raising the temperature of a heat exchange medium flowing through the power battery 107, and as the boost module 102, the three-phase inverter 104 and the three-phase alternating current motor 105 all generate heat during the work, therefore, the boosting module 102, the three-phase inverter 104, and the three-phase ac motor 105 may be controlled to heat the heat transfer medium flowing through the power battery 107, and the heat transfer medium may be heated by alternately operating some of the boosting module 102, the three-phase inverter 104, and the three-phase ac motor 105, controlling the first switching module 103, the second switching module 106, the boosting module 102, the three-phase inverter 104, the three-phase ac motor 105, and the three-phase inverter 104 to form a charging circuit with the first switching module 103, the second switching module 106, the boosting module 102, the three-phase inverter 104, the three-phase ac motor 105, and the power battery 107 to take out power to heat the boosting module 102 and the three-phase ac motor 105, turning off the power battery 107 after heating is completed, and forming a discharging circuit with the first switching module 103, the boosting module 102, the three-phase inverter 104, and the three-phase ac motor 105 to discharge the boosting module 102 and the three-phase inverter 104, so that the boosting module 102, the three-phase inverter 104 and the three-phase ac motor 105 heat the heat exchange medium flowing through the power battery 107, and the battery is heated by combining the battery discharge heat. This application embodiment draws forth the neutral conductor in three-phase AC motor, and then with power battery, boost module and three-phase inverter constitute different return circuits, through the inside three-phase coil of three-phase AC motor, three-phase inverter and boost module and inside device that generates heat provide the heat source, the valve body switches over the cooling circuit that makes the heat transfer medium after the heating flow into power battery place behind the heating heat transfer medium, the realization is to power battery's heating, need not use the engine or increase motor control circuit and just can realize promoting power battery's temperature, combine the battery to discharge the heat production simultaneously, heating efficiency is high, power battery temperature risees soon.

As for the boost module 102, as shown in fig. 2, as an embodiment, the control module 108 controls the second switching module 106 to be turned on, and by controlling the first switching module 103, the three-phase inverter 104, the seventh power switching unit 112, and the eighth power switching unit 113, the charging process of the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105 by the power battery 107 and the discharging process of the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105 are alternately performed.

In this embodiment, the energy storage unit 111, the seventh power switch unit 112, and the eighth power switch unit 113 are provided in the boost module 102, and when the seventh power switch unit 112 or the eighth power switch unit 113 is controlled to be turned on, the power battery 107 is caused to charge the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105, in the charging process, the energy storage unit 111 and the three-phase ac motor 105 are heated by taking power from the power battery 107, and the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105 are caused to discharge to the outside, the energy storage unit 111 is provided in the boost module 102 to store electric energy or release electric energy, and the energy storage unit 111 is controlled to alternately charge and discharge, so that the energy storage unit 111, the three-phase inverter 104, and the three-phase ac motor 105 are caused to heat a heat transfer medium flowing through the power battery 107.

When the power battery 107 can discharge, as an embodiment, as shown in fig. 3, the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 may be controlled to heat the heat transfer medium flowing through the power battery 107 in the following manner: the power battery 107, the third switch, the three-phase inverter 104, the three-phase alternating current motor 105, the energy storage unit 111, the eighth power switch unit 113, the first switch 132 and the fourth switch form a first energy storage loop, and the energy storage unit 111, the eighth power switch unit 113, the first switch 132, the three-phase inverter 104 and the three-phase alternating current motor 105 form a first free-wheeling loop.

Control first switch module, second switch module, boost module and three-phase inverter, make power battery go on in turn to the charging process of the three-phase coil of boost module and three-phase alternating current motor and the discharging process of the three-phase coil of boost module and three-phase alternating current motor, include:

the control module controls the second switch module, the first switch and the eighth power switch unit to be conducted, and controls the three-phase inverter to enable the first energy storage loop and the first follow current loop to be conducted alternately.

The first energy storage loop forms an inductive energy storage loop, and in the process that the power battery 107 charges the inductive energy storage loop, the boosting module 102, the three-phase alternating-current motor 105 and the three-phase inverter 104 start to work to heat a heat exchange medium; when the control module 108 controls the first freewheeling circuit to be turned on, the energy storage unit 111 and the three-phase ac motor 105 both output currents, that is, in the process of alternately turning on the first energy storage circuit and the first freewheeling circuit, the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 are in an operating state.

When the power battery 107 can discharge, as another embodiment, as shown in fig. 3, the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 may be controlled to heat the heat transfer medium flowing through the power battery 107 in the following manner: the power battery 107, the three-phase inverter 104, the three-phase ac motor 105, the energy storage unit 111, the eighth power switching unit 113, and the first switch 132 form a first energy storage circuit, and the energy storage unit 111, the seventh power switching unit 112, the fifth switch 131, the three-phase inverter 104, and the three-phase ac motor 105 form a second flywheel circuit.

the control module 108 controls the second switch module 106, the first switch 132 and the fifth switch 131 to be turned on, and controls the three-phase inverter 104, the seventh power switch unit 112 and the eighth power switch unit 113 to alternately turn on the first tank circuit and the second freewheeling circuit.

The present embodiment is the same as the above-described embodiment in that the first tank circuit is formed, and the present embodiment is different from the above-described embodiment in that the control module 108 controls the first switch 132 to be turned off and the fifth switch 131 to be turned on, so that a second flywheel circuit having a different configuration from the first flywheel circuit is formed, and when the first tank circuit is turned on, the boost module 102, the three-phase ac motor 105, and the three-phase inverter 104 start to operate to heat the heat exchange medium; when the control module 108 controls the second freewheeling circuit to be turned on, the energy storage unit 111 and the three-phase ac motor 105 both output current, so that the second freewheeling circuit forms a current freewheeling circuit, that is, in the process of alternately turning on the first energy storage circuit and the second freewheeling circuit, the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 are in the operating state.

In the two embodiments, the N-shaped linear wire is led out from the three-phase alternating current motor, the first switch and the fifth switch form different loops with the power battery, the boosting module and the three-phase inverter, a heat source is provided through the three-phase coil inside the three-phase alternating current motor, the three-phase inverter, the boosting module and the internal heating device thereof, the heating of the power battery is realized through the original cooling loop after the heat exchange medium is heated, the temperature of the power battery can be increased without using an engine or adding a motor control circuit, the heating efficiency is high, and the temperature of the power battery is quickly increased.

Further, as an embodiment, before controlling the boosting module 102, the three-phase inverter 104, and the three-phase ac motor 105 to heat the heat transfer medium flowing through the power battery 107, the control module 108 needs to determine whether the received information meets a preset condition, where the preset condition may include, in addition to the determination of the temperature value of the power battery 107, other determination conditions:

the control module 108 acquires a state signal (such as a state signal which can be determined by gear information and a vehicle speed signal) of the three-phase alternating current motor, a temperature signal of the power battery 107 and a gun plugging signal;

when the control module 108 judges that the state signal of the three-phase alternating current motor is in a non-driving state (for example, the state signal can be determined by whether the gear is in a P gear and the vehicle speed is zero), whether the temperature of the power battery 107 is lower than a preset temperature value is judged;

when the control module 108 determines that the temperature of the power battery 107 is lower than a preset temperature value, the second switch module 106, the first switch module 103, the boost module 102 and the three-phase inverter 104 are controlled to alternately conduct the first energy storage loop and the first follow current loop or the first energy storage loop and the second follow current loop, so that the boost module 102, the three-phase inverter 104 and the three-phase alternating current motor 105 heat a heat exchange medium flowing through the power battery 107, and the first switch module 103, the second switch module 106, the boost module 102 and the three-phase inverter 104 are controlled to be turned off until a state signal of the three-phase alternating current motor is in a driving state or the temperature of the power battery 107 is not lower than the preset temperature value is obtained;

when the control module 108 judges that the temperature of the power battery 107 is not lower than the preset temperature value, the state signal of the three-phase alternating current motor and the temperature information of the power battery 107 are obtained again.

When the preset conditions are that the current gear is the P gear, the vehicle speed is 0, and the temperature of the power battery 107 does not reach the preset temperature value, that is, the temperature of the power battery 107 obtained when the vehicle is in the parking state is low, the control module 108 controls the boosting module 102, the three-phase inverter 104 and the three-phase alternating current motor 105 to heat the heat exchange medium flowing through the power battery 107, and when one of the preset conditions which is obtained by circularly obtaining the current gear, the vehicle speed and the temperature of the power battery 107 in the heating process does not meet is obtained, the heating is stopped, and all the switch modules are controlled to be switched off.

In the present embodiment, when the state signal of the three-phase ac motor and the temperature information of the power battery 107 obtained in the parking state satisfy the preset conditions, the power battery 107 is controlled to output the current, and the heat transfer medium flowing through the power battery 107 is heated by the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105, so that the power battery 107 is heated in the parking state of the electric vehicle, and the electric vehicle can be normally started in the low temperature condition.

Next, the process of heating by taking power from the power battery through a specific circuit structure is shown in fig. 4, which is a circuit diagram illustrating an example of the motor control circuit of the present application, and a loop for storing energy to the energy storage unit and the three-phase ac motor by taking power from the power battery includes a first energy storage loop and a second energy storage loop, as shown in fig. 7, the first energy storage loop is: discharging the power battery 107, wherein current passes through a positive electrode of the power battery 107, a switch K3, an upper bridge power switch (a first upper bridge arm VT1, a third upper bridge arm VT3 and a fifth upper bridge arm VT5) of the three-phase inverter 104, a three-phase coil of the motor, an inductor L, an eighth lower bridge arm VT8 and a first energy storage loop formed by a switch K1, and the inductor L and the three-phase coil of the motor are charged by the power battery 107; as shown in fig. 8, the second tank circuit is: the power battery 107 discharges, and current passes through a second energy storage loop formed by the positive electrode of the power battery 107, the switch K3, the switch K5, the seventh upper bridge arm VT7, the inductor L, the three-phase coil of the motor, the lower bridge power switches (the second lower bridge arm VT2, the fourth lower bridge arm VT4 and the sixth lower bridge arm VT6) of the three-phase inverter 104 and the switch K4, so that the inductor L and the three-phase coil of the motor are charged by the power battery 107.

Carry out the afterflow through control switch module after accomplishing the energy storage, energy storage unit and three-phase alternating current motor carry out the afterflow, and the afterflow return circuit that corresponds with first energy storage return circuit includes first afterflow return circuit and second afterflow return circuit, as shown in fig. 9, first afterflow return circuit is: the current flowing out of the inductor L passes through an eighth lower bridge arm VT8, a switch K1, a lower bridge power switch (a second lower bridge diode VD2, a fourth lower bridge diode VD4 and a sixth lower bridge diode VD6) and a three-phase coil of the motor to form a first follow current loop; as shown in fig. 10, the second freewheel loop is: the current flowing out of the inductor L passes through a seventh upper bridge diode VD7, a switch K5, an upper bridge power switch (a first upper bridge arm VT1, a third upper bridge arm VT3 and a fifth upper bridge arm VT5) and a three-phase coil of the motor to form a second freewheeling circuit.

The freewheel circuits corresponding to the second tank circuit include a third freewheel circuit and a fourth freewheel circuit, as shown in fig. 11, the third freewheel circuit is: the current flowing out of the inductor L passes through a three-phase coil of the motor, a lower bridge power switch (a second lower bridge arm VT2, a fourth lower bridge arm VT4, a sixth lower bridge arm VT6), a switch K1 and an eighth lower bridge diode VD8 to form a third freewheeling circuit; as shown in fig. 12, the fourth freewheel loop is: the current flowing out of the inductor L passes through a three-phase coil of the motor, an upper bridge power switch (a first upper bridge diode VD1, a third upper bridge diode VD3 and a fifth upper bridge diode VD5), a switch K5 and a seventh upper bridge arm VT7 to form a second freewheeling circuit.

Therefore, the control steps of the control module 108 specifically include:

step 1, when the whole vehicle is electrified, state signals (for example, the state signals can be determined through gear information and a vehicle speed signal) of a three-phase alternating current motor of the whole vehicle controller and temperature signals of a power battery 107 sent by a battery manager are sent.

And 2, acquiring whether the state signal of the three-phase alternating current motor is in a non-driving state or not by the vehicle controller (for example, whether the gear is in a P gear or not and whether the vehicle speed is zero or not can be determined).

And 3, if not, exiting the motor heating program.

And 4, if so, judging whether the temperature of the power battery 107 is lower than a set threshold value.

And 5, if not, exiting the motor heating program.

And 6, if so, the vehicle control unit sends a battery heating instruction and heating power to the battery manager and the motor controller.

Step 7, the battery manager controls the switch K1, the switch K3 and the switch K4 to be switched on, controls the switch K5 to be switched off, and controls the first energy storage loop and the first follow current loop to be alternately switched on by the motor controller; or the first energy storage circuit and the second freewheeling circuit are controlled to be alternately conducted, or the battery manager controls the switch K1, the switch K3, the switch K4 and the switch K5 to be switched on, and the motor controller controls the second energy storage circuit and the third freewheeling circuit to be alternately conducted; or the second energy storage loop and the fourth freewheeling loop are controlled to be alternately conducted.

And 8, receiving voltage and current data of the power battery 107 by the motor controller, calculating output power, regarding the output power as battery heating power, comparing the calculated battery heating power with heating command power sent by the battery manager, increasing the PWM duty ratio and increasing the battery output current if the calculated heating power is low, and decreasing the PWM duty ratio and the battery output current if the calculated heating power is high until the heating power reaches the vicinity of the heating command power.

And 9, circularly acquiring a state signal of the three-phase alternating current motor and the temperature of the power battery 107 by the vehicle control unit, repeating the steps 2-8 if the condition is met, and exiting the heating program if the condition is not met.

And step 10, if the heating condition is not met, exiting the heating program, controlling the upper bridge and the lower bridge of the boosting module 102 and the three-phase inverter 104 to be completely switched off by the motor controller, and controlling all switches to be switched off by the battery manager.

It should be noted that, with the embodiment in fig. 6, only the first tank circuit and the first freewheel circuit or the second tank circuit and the third freewheel circuit can be implemented.

Based on the above-mentioned motor control circuit, as shown in fig. 3, when the power battery 107 cannot discharge, for example, the power battery is at an extremely low temperature or the power battery 107 has a low electric quantity, the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 may be controlled to heat the heat transfer medium flowing through the power battery 107 in the following manner: the boosting module 102 is also connected with an external power supply module 101, and the external power supply module 101 is connected with a control module 108; when the control module 108 obtains that the external power module is connected and the component to be heated needs to be heated, for example, when the temperature of the power battery 107 is lower than a preset temperature value, and the electric quantity of the power battery 107 is lower than a preset electric quantity value, or the temperature of the power battery 107 is lower than a preset temperature value, by controlling the first switch module 103, the second switch module 106, the voltage boost module 102, and the three-phase inverter 104, the external power module 101 is enabled to alternately perform the charging process of the three-phase coils of the voltage boost module 102 and the three-phase alternating current motor 105 and the discharging process of the three-phase coils of the voltage boost module 102 and the three-phase alternating current motor 105, so that the voltage boost module 102, the three-phase inverter 104, and the three-phase alternating current motor 105 heat a heat transfer medium flowing through at least one of the voltage boost module 102, the three-phase inverter 104, and the three-phase alternating current motor 105 when the heat transfer medium flows through the power battery, the temperature of the power battery is increased.

For example, when the dc charging gun is plugged into the dc charging pile interface, the temperature detection circuit determines the battery temperature and the preset charging temperature, when the battery temperature is lower than the chargeable temperature, the power battery needs to be heated first, and when the power battery temperature is higher than the chargeable temperature, the battery is charged, and at this time, the power battery 107 cannot be discharged, the control module 108 controls the external power module 101 to provide power to charge the boost module 102 and the three-phase coil of the three-phase ac motor 105, and discharges the boost module 102 and the three-phase coil of the three-phase ac motor 105, so that the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 heat the heat transfer medium flowing through the power battery 107, in this embodiment, by being connected to the external power module 101, when the power battery 107 cannot normally release electric energy under a low-temperature condition, the external power module 101 and other devices form a charging and discharging loop to heat the power battery 107, so that the normal operation of the power battery 107 is realized.

As an embodiment, as shown in fig. 3, when the external power module is connected, the charging process of the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105 and the discharging process of the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105 by the external power module 101 are alternately performed.

In the present embodiment, the energy storage unit 111, the seventh power switching unit 112, and the eighth power switching unit 113 are provided in the boost module 102, and when the seventh power switching unit 112 or the eighth power switching unit 113 is controlled to be turned on, the external power supply module 101 is caused to charge the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105, and the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105 are caused to discharge to the outside, so that the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 heat the heat transfer medium flowing through the power battery 107 during the charging and discharging processes.

When the power battery 107 cannot discharge through the external power module 101, as an embodiment, as shown in fig. 3, the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 may be controlled to heat the heat transfer medium flowing through the power battery 107 in the following manner: the first switch module 103 comprises a first switch 132 and a fifth switch 131, a first end of the first switch 132 is connected with the output end of the eighth power switch unit 113 and the external power supply module 101, a second end of the first switch 132 is connected with the output end of the three-phase inverter 104 and the second switch module 106, a first end of the fifth switch 131 is connected with the input end of the seventh power switch unit 112 and the external power supply module 101, and a second end of the fifth switch 131 is connected with the input end of the three-phase inverter 104 and the second switch module 106; the external power supply module 101, the seventh power switch unit 112, the energy storage unit 111, the three-phase ac motor 105, the three-phase inverter 104, and the first switch 132 form a third energy storage loop, and the energy storage unit 111, the three-phase ac motor 105, the three-phase inverter 104, the first switch 132, and the eighth power switch unit 113 form a third freewheeling loop.

the control module 108 controls the second switch module 106 to be turned off, the fifth switch 131 to be turned off, and the first switch 132 to be turned on, and controls the three-phase inverter 104, the seventh power switch unit 112, and the eighth power switch unit 113 to alternately turn on the third tank circuit and the third freewheel circuit.

In the process that the external power supply module 101 charges the third energy storage loop, the boosting module 102, the three-phase alternating-current motor 105 and the three-phase inverter 104 start to work to heat a heat exchange medium; when the control module 108 controls the third freewheeling circuit to be turned on, the energy storage unit 111 and the three-phase ac motor 105 both output current, that is, in the process of alternately turning on the third energy storage circuit and the third freewheeling circuit, the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 are in a working state.

When the power battery 107 cannot discharge through the external power module 101, as another embodiment, as shown in fig. 3, the boost module 102, the three-phase inverter 104, and the three-phase ac motor 105 may be controlled to heat the heat transfer medium flowing through the power battery 107 in the following manner: the external power supply module 101, the seventh power switch unit 112, the energy storage unit 111, the three-phase alternating current motor 105, the three-phase inverter 104 and the first switch 132 form a third energy storage loop, and the energy storage unit 111, the three-phase alternating current motor 105, the three-phase inverter 104, the fifth switch 131 and the seventh power switch unit 112 form a fourth freewheeling loop; the control module 108 controls the second switching module 106 to be turned off, the first switch 132 to be turned on, the eighth power switching unit 113 to be turned on, and the eighth power switching unit 113 to be turned off, and controls the three-phase inverter 104 to alternately turn on the third tank circuit and the fourth freewheeling circuit.

The present embodiment is the same as the above-described embodiment in that the third tank circuit is formed, and is different from the above-described embodiment in that the control module 108 controls the first switch 132 to be turned off and the fifth switch 131 to be turned on, so that a fourth freewheel circuit having a different structure from the third freewheel circuit is formed, and the third tank circuit is controlled to be turned on, so that the boost module 102, the three-phase ac motor 105, and the three-phase inverter 104 start to operate as the heat exchange medium to heat; when the control module 108 controls the fourth freewheeling circuit to be turned on, the energy storage unit 111 and the three-phase ac motor 105 both output current, that is, in the process of alternately turning on the third energy storage circuit and the fourth freewheeling circuit, the boost module 102, the three-phase inverter 104 and the three-phase ac motor 105 are in an operating state, in this embodiment, the third energy storage circuit and the fourth freewheeling circuit are alternately turned on by the first switch 132 and the fifth switch 131 in the first switch module 103, so that the boost module 102, the three-phase inverter 104 and the three-phase ac motor 105 heat the heat exchange medium flowing through the power battery 107.

The following process of heating by taking electricity from the external power module through a specific circuit structure, wherein the loop for storing energy to the energy storage unit and the three-phase alternating-current motor by taking electricity from the external power module comprises a third energy storage loop and a fourth energy storage loop, and as shown in fig. 13, the third energy storage loop is as follows: discharging by the external power supply module 101, wherein current passes through a third energy storage loop formed by a positive electrode of the external power supply module 101, a seventh upper bridge arm VT7, an inductor L, a three-phase coil of the motor, a lower bridge power switch (a second lower bridge arm VT2, a fourth lower bridge arm VT4 and a sixth upper bridge arm VT6) of the three-phase inverter 104 and a switch K1, and the inductor L and the three-phase coil of the motor are charged by the external power supply module 101; as shown in fig. 14, the fourth tank circuit is: the external power supply module 101 discharges, current passes through a positive electrode of the external power supply module 101, a first energy storage loop formed by an upper bridge power switch (a first upper bridge arm VT1, a third upper bridge arm VT3 and a fifth upper bridge arm VT5) of the three-phase inverter 104, a three-phase coil of the motor, an inductor L and an eighth lower bridge arm VT8, and the inductor L and the three-phase coil of the motor are charged by the external power supply module 101.

After energy storage is completed, follow current is performed through the control switch module, the energy storage unit and the three-phase alternating-current motor perform follow current, the follow current circuit corresponding to the third energy storage circuit comprises a third follow current circuit (please refer to fig. 11) and a fourth follow current circuit (please refer to fig. 12), and the follow current circuit corresponding to the fourth energy storage circuit comprises a first follow current circuit (please refer to fig. 9) and a second follow current circuit (please refer to fig. 10).

When the power battery 107 is at an extremely low temperature or the battery power is extremely low, and the power battery 107 cannot be heated by the self-discharge of the battery, an external power supply device is required to heat the battery, and in order to heat the battery, the control steps of the control module 108 specifically include:

step 1, when the whole vehicle is powered on, a state signal (for example, the state signal can be determined by gear information and a vehicle speed signal) of a three-phase alternating current motor, a temperature signal of a power battery 107 sent by a battery manager and a gun plugging signal are sent.

And 2, judging whether the state signal of the three-phase alternating current motor of the vehicle control unit is in a non-driving state (for example, the state signal can be determined by judging whether the gear is in a P gear and whether the vehicle speed is zero).

And 3, if not, exiting the motor heating program.

And 4, if yes, judging whether the temperature of the power battery 107 is lower than a set threshold value.

And 5, if not, exiting the motor heating program.

Step 6, if the gun inserting signal is received, and the power battery 107 is at an extremely low temperature or the battery electric quantity is extremely low, the vehicle control unit sends a battery heating instruction and heating power to the battery manager and the motor controller;

step 7, the battery manager controls the switch K1 and the switch K5 to be switched on, and the motor controller controls the third energy storage loop and the third follow current loop to be alternately switched on; or the third energy storage circuit and the fourth freewheeling circuit are controlled to be alternately conducted, or the battery manager controls the switch K1 and the switch K5 to be switched on, and the motor controller controls the fourth energy storage circuit and the first freewheeling circuit to be alternately conducted; or the fourth energy storage loop and the second freewheeling loop are controlled to be alternately conducted.

And 9, the motor controller is connected with voltage and current data of the external power supply module 101, calculates output power, regards the output power as heating power, compares the calculated heating power with heating instruction power sent by the battery manager, increases the PWM duty ratio and increases the output current of the battery if the calculated heating power is low, and decreases the PWM duty ratio and decreases the output current of the battery until the heating power reaches the vicinity of the heating instruction power if the calculated heating power is high.

And step 10, circularly acquiring the state signal, the gun inserting signal and the temperature of the power battery 107 of the three-phase alternating current motor by the vehicle control unit, repeating the steps 2-9 when the conditions are met, and exiting the heating program when the conditions are not met.

And 11, if the heating condition is not met, exiting the heating program, controlling the upper bridge and the lower bridge of the boost module 102 and the three-phase inverter 104 to be completely switched off by the motor controller, and controlling the switch K1 and the switch K3 to be switched off by the battery manager.

The fourth embodiment of the present application provides a charging method for a vehicle, where the charging method includes:

acquiring the voltage of an external power supply module and the voltage of a power battery, and selecting a charging mode according to the voltage of the external power supply module and the voltage of the power battery, wherein the charging mode comprises boosting charging, voltage reduction charging and direct charging;

and controlling the first switch module, the second switch module, the boosting module and the three-phase inverter to enable the external power supply module to charge the power battery according to the selected charging mode.

As an embodiment, the voltage of the external power supply module and the voltage of the power battery are obtained, and the charging mode is selected according to the voltage of the external power supply module and the voltage of the power battery:

when the highest output voltage of the external power supply module is acquired to be lower than the voltage of the power battery, a boosting charging mode is selected;

controlling the first switch module, the second switch module, the boost module, and the three-phase inverter to charge the power battery according to the selected charging method, including:

when the control module 108 obtains that the maximum output voltage of the external power supply module 101 is lower than the voltage of the power battery 107, the control module 108 controls the first switch module 103, the second switch module 106, the boost module 102 and the three-phase inverter 104 to alternately perform the charging process of the boost module 102 and the three-phase coil of the three-phase alternating-current motor 105 by the external power supply module 101 and the discharging process of the power battery 107 by the three-phase coil of the external power supply module 101, the boost module 102 and the three-phase alternating-current motor 105, so that the charging voltage of the external power supply module 101 is boosted to exceed the voltage of the power battery 107 and then the power battery 107 is charged.

When the power battery 107 needs to be charged, the control module 108 controls the external power module 101 to charge the power battery 107, the control module 108 first obtains the magnitude relationship between the output voltage of the external power module 101 and the voltage of the power battery 107, when the highest output voltage of the external power module 101 is less than the voltage of the power battery 107, the control module 108 needs to boost the voltage output by the external power module 101, the boost mode may be that the boost module 102 is arranged, a charging loop is formed by the external power module 101, the boost module 102 and the three-phase alternating current motor 105, so that the external power module 101 charges the boost module 102 and the three-phase alternating current motor 105, after the charging is completed, the three-phase coils of the external power module 101, the boost module 102 and the three-phase alternating current motor 105 discharge the power battery 107, and because the boost module 102 and the three-phase coils of the three-phase alternating current motor 105 store electric energy, therefore, the voltage obtained by superimposing the discharge voltage of the external power supply module 101 and the discharge voltage of the boost module 102 and the three-phase ac motor 105 is greater than the voltage of the power battery 107, and at this time, the external power supply module 101 can charge the power battery 107.

In the present embodiment, a neutral line is drawn out of the three-phase ac motor 105, and a circuit different from the external power supply module 101, the boost module 102, and the three-phase inverter 104 is formed, the external power supply module 101 charges the three-phase coil and the boost module 102 inside the three-phase ac motor 105, and the external power supply module 101, the three-phase ac motor 105, and the boost module 102 discharge the power battery 107, thereby achieving normal charging of the power battery 107 when the voltage of the external power supply module 101 is lower than the voltage of the power battery 107.

As an embodiment, as shown in fig. 5, the boost module 102 includes an energy storage unit 111, a seventh power switching unit 112, and an eighth power switching unit 113, wherein one end of the energy storage unit 111 is connected to a middle point of a three-phase coil connection of the three-phase ac motor 105, the other end of the energy storage unit 111 is connected to an output terminal of the seventh power switching unit 112 and an input terminal of the eighth power switching unit 113, an input terminal of the seventh power switching unit 112 is connected to the external power supply module 101, and an output terminal of the eighth power switching unit 113 is connected to the first switching module 103 and the external power supply module 101.

The control module 108 controls the second switch module 106 to be turned on, the seventh power switch unit 112 to be turned on, and the eighth power switch unit 113 to be turned off, and controls the first switch module 103 and the three-phase inverter 104 to alternately perform a charging process of the external power supply module 101 on the three-phase coils of the boost module 102 and the three-phase ac motor 105 and a discharging process of the external power supply module 101, the boost module 102 and the three-phase ac motor 105 on the power battery 107.

In the present embodiment, the energy storage unit 111, the seventh power switching unit 112, and the eighth power switching unit 113 are provided in the boost module 102, and when the seventh power switching unit 112 or the eighth power switching unit 113 is controlled to be turned on, the power battery 107 is caused to charge the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105, and the energy storage unit 111 and the three-phase coil of the three-phase ac motor 105 are caused to discharge to the outside, and by providing the energy storage unit 111 in the boost module 102 to store electric energy or release electric energy, and by controlling the energy storage unit 111 to alternately perform charging and discharging, a boost process of the boost module 102 and the three-phase ac motor 105 to the external power supply module 101 is realized, and the power battery 107 can be normally charged even when the voltage output by the external power supply module 101 is lower than the voltage of the power battery 107.

As an embodiment, the first switch module 103 includes a first switch 132 and a fifth switch 131, a first end of the first switch 132 is connected to the output end of the eighth power switch unit 113 and the external power supply module 101, a second end of the first switch 132 is connected to the output end of the three-phase inverter 104 and the second switch module 106, a first end of the fifth switch 131 is connected to the input end of the seventh power switch unit 112 and the external power supply module 101, and a second end of the fifth switch 131 is connected to the input end of the three-phase inverter 104 and the second switch module 106.

The external power supply module 101, the seventh power switch unit 112, the energy storage unit 111, the three-phase alternating current motor 105, the three-phase inverter 104 and the first switch 132 form a third energy storage loop, and the external power supply module 101, the seventh power switch unit 112, the energy storage unit 111, the three-phase alternating current motor 105, the three-phase inverter 104, the power battery 107 and the first switch 132 form a first charging loop.

The control module 108 controls the second switching module 106 to be turned on, the fifth switch 131 to be turned off, and the first switch 132 to be turned on, and controls the three-phase inverter 104, the seventh power switching unit 112, and the eighth power switching unit 113 to alternately turn on the third tank circuit and the first charging circuit.

When the third energy storage loop is turned on, the energy storage unit 111 and the three-phase alternating current motor 105 start to store energy in a segment in the process that the external power supply module 101 charges the inductive energy storage circuit; when the control module 108 controls the first charging loop to be turned on, the external power module 101, the energy storage unit 111, and the three-phase ac motor 105 all output current, that is, in the process of alternately turning on the third energy storage loop and the first charging loop, the external power module 101 charges the energy storage unit 111 and the three-phase inverter 104 first, and the external power module 101, the boosting module 102, and the three-phase inverter 104 discharge the power battery 107.

The following describes a process of charging the power battery by boosting the external power module through a specific circuit structure, and for the third tank circuit and the first charging circuit: as shown in fig. 13, a circuit diagram of a third energy storage loop is formed for the external power supply module 101, the external power supply module 101 stores energy in the inductor L and the three-phase ac motor 105, and as shown in fig. 15, a first charging loop current flow diagram is formed, in which the first charging loop current flows to the external power supply module, the seventh upper bridge arm VT7, the inductor L, the three-phase ac motor 105, the upper bridge power switch (the first upper bridge diode VD1, the third upper bridge diode VD3, the fifth upper bridge diode VD5), the third switch K3, the power battery 107, the fourth switch K4, and the first switch K1 of the three-phase inverter 104, so that the external power supply module 101 boosts the voltage to charge the power battery 107, and the external power supply module 101 boosts the voltage and charges the external power supply module 101 by controlling the conduction and the disconnection of the three switching tubes of the three-phase lower bridge arm through the PWM waves of the switches VT2, VT4, VT 6. Therefore, the power battery 107 can be boosted and charged under the condition that the voltage of the power battery 107 is higher than the output voltage of the external power supply module 101, and the three-phase coils of the motor are directly connected and disconnected together during the boosting and charging, so that the three-phase current deviation is small, and the characteristics of no current and no torque output of the motor winding in the whole boosting and charging process can be realized.

As another embodiment, the voltage of the external power supply module and the voltage of the power battery are obtained, and the charging mode is selected according to the voltage of the external power supply module and the voltage of the power battery:

when the lowest output voltage of the external power supply module is obtained to be higher than the voltage of the power battery, a step-down charging mode is selected;

control first switch module, second switch module, boost module and three-phase inverter, make external power source module charge to power battery according to the selected mode of charging, include:

the control module 108 controls the first switch module 103, the second switch module 106, the boost module 102, and the three-phase inverter 104 to alternately perform a discharging process of the external power supply module 101 on the boost module 102, the three-phase coil of the three-phase ac motor 105, and the power battery 107, and a charging process of the boost module 102 and the three-phase coil of the three-phase ac motor 105 on the power battery 107, so that the charging voltage of the external power supply module 101 is reduced and then the power battery 107 is charged.

When the power battery 107 needs to be charged, the control module 108 controls the external power module 101 to charge the power battery 107, the control module 108 first obtains the magnitude relation between the output voltage of the external power module 101 and the voltage of the power battery 107, when the lowest output voltage of the external power module 101 is greater than the voltage of the power battery 107, the control module 108 needs to step down the voltage output by the external power module, and the external power module is the seventh power switch unit, the energy storage unit, the three-phase alternating current motor, the three-phase inverter, the first switch forms a first energy storage charging loop, so that the external power module 101 is right the energy storage unit and the three-phase alternating current motor 105 store energy, and the power battery is charged through the energy storage unit and the three-phase alternating current motor 105, so that the power battery 107 is discharged after the output voltage of the external power module is stepped down.

In the embodiment, a neutral line is led out from a three-phase alternating current motor, so that different loops are formed by the neutral line, an external power module, a boosting module and a three-phase inverter, and when the voltage of the external power module detected by a control module is higher than the voltage of a power battery, the original energy storage module and the original three-phase alternating current motor are adopted to reduce the voltage of the external power module and then charge the power battery; when the control module detects that the voltage of the power battery is within the charging voltage range of the external power supply module, the external power supply module is directly charged, the external power supply module can be charged no matter the voltage of the power battery is high or low, compatibility adaptability is high, an external booster circuit does not need to be additionally added, and the cost of an additional circuit is reduced.

Further, the external power supply module, the seventh power switch unit, the energy storage unit, the three-phase ac motor, the three-phase inverter, and the first switch form a first energy storage charging loop, and the energy storage unit, the three-phase ac motor, the three-phase inverter, the third switch, the power battery, the fourth switch, the first switch, and the eighth power switch unit form a second charging loop;

controlling the first switch module, the second switch module, the boost module, and the three-phase inverter to alternately perform a discharging process of the boost module, the three-phase ac motor, and the three-phase coil of the power battery by the external power supply module and a discharging process of the power battery by the boost module and the three-phase coil of the three-phase ac motor, including:

the control module controls the third switch, the fourth switch, the fifth switch and the first switch to be switched on, and controls the three-phase inverter, the seventh power switch unit and the eighth power switch unit to enable the first energy storage charging loop and the second charging loop to be switched on alternately.

The following describes the step-down charging of the power battery by the external power supply module through a specific circuit structure: as shown in fig. 15, the external power module 101 forms a circuit diagram of a first energy storage charging circuit, which is the same as the first charging circuit described above, but the principle of the first energy storage charging circuit is different, the first charging circuit is that the external power module, the inductor and the three-phase coil charge the power battery at the same time, the external power module charges the power battery while storing energy in the inductor and the three-phase coil, the external power module can be reduced in voltage and then charges the power battery due to the voltage division function of the inductor and the three-phase coil, the external power module 101 stores energy in the inductor L and the three-phase ac motor 105, as shown in fig. 16, the inductor L, the three-phase ac motor 105, the three-phase inverter (the first upper bridge diode VD1, the third upper bridge diode VD3, the fifth upper bridge diode VD5), the third switch K3, The current of the second charging loop formed by the power battery 107, the fourth switch K4, the first switch K1 and the eighth power switch unit flows to the graph, so that the external power module 101 is boosted to charge the power battery 107, and the external power module 101 is charged with reduced voltage by controlling the on and off of the switch tubes through the PWM waves of the switches VT7 and VT 8.

The following describes the direct charging of the power battery by the external power supply module through a specific circuit structure: as shown in fig. 17, when the external power module 101 charges the power battery 107, and when the control module 108 obtains that the voltage output by the external power module 101 matches the voltage of the power battery, for example, the voltage output by the external power module 101 is greater than or equal to the voltage of the power battery, the control switches K1, K5, K3, and K4 are turned on, because the direct current of the external power module 101 directly charges the power battery, and during the period, the direct current does not pass through the power tube and the inductor, the loss is small, the efficiency is high, and the direct charging is realized.

The fourth embodiment of the present invention provides a discharging method for a power battery, where based on the motor control circuit provided in the first embodiment, when the motor control circuit is connected to the power module, the discharging method includes:

acquiring the voltage of the power utilization module and the voltage of the power battery, and selecting a discharging mode according to the voltage of the power utilization module and the voltage of the power battery, wherein the discharging mode comprises boosting discharging, reducing discharging and direct discharging;

One embodiment is boost charging, and the selecting the discharging mode according to the voltage of the power module and the voltage of the power battery comprises:

when the highest output voltage of the power battery is detected to be lower than the electricity utilization voltage of the electricity utilization module, a boosting charging mode is selected;

controlling the first switch module, the second switch module, the three-phase inverter, and the boost module to enable the power battery to output direct current, and enabling the power battery to discharge the power module according to the selected discharge mode, including:

the control the boost module, the first switch module, the second switch module and the three-phase inverter, so that the power battery alternately performs the energy storage process of the energy storage module, the three-phase coil of the three-phase alternating current motor and the energy storage process of the power utilization module and the discharge process of the power battery, the energy storage module and the three-phase coil of the three-phase alternating current motor and the power utilization module, and the power supply module is discharged after the discharge voltage of the power battery is boosted.

The other embodiment is step-down charging, and the selecting of the discharging mode according to the voltage of the power module and the voltage of the power battery comprises:

when the lowest output voltage of the power battery is detected to be higher than the electricity utilization voltage of the electricity utilization module, a step-down charging mode is selected;

and controlling the boosting module, the first switch module, the second switch module and the three-phase inverter to enable the power battery to alternately perform the energy storage process of the energy storage module, the three-phase coil of the three-phase alternating current motor and the energy storage process of the power utilization module and the discharging process of the energy storage module and the three-phase coil of the three-phase alternating current motor on the power utilization module, so that the discharging voltage of the power battery is reduced and then the power supply module is discharged.

Next, a process of charging the power module by the boosting of the power battery is described through a specific circuit structure, as shown in fig. 18, a path diagram of a first energy storage loop is formed when the power battery charges the power module, in order to realize the boosting and charging of the power battery to the power module, the power battery charges an inductor L and a three-phase coil through the first energy storage loop, and then the first discharging loop is turned on after the charging is completed, as shown in fig. 19, the first discharging loop discharges the power battery 107, a current passes through a positive electrode of the power battery 107, a switch K3, an upper bridge power switch (a first upper bridge arm VT1, a third upper bridge arm VT3, a fifth upper bridge arm VT5), a three-phase coil of a motor, an inductor L, a seventh upper bridge diode 7, the power module, and a negative electrode of the power battery 107, and when the first discharging loop is turned on, the power battery, the inductor VD and the three-phase coil discharge the power module simultaneously, through the alternate conduction of the first energy storage loop and the first discharging loop, the power battery is discharged after being boosted.

In order to implement the step-down charging of the power module by the power battery, as shown in fig. 19, the power battery charges the inductor L and the three-phase coil through the first energy storage discharging loop, which is the same as the first discharging loop, but has a different principle, the first discharging loop is that the power battery, the inductor and the three-phase coil charge the ground module at the same time, and the first energy storage charging loop operates according to the principle that the power battery stores energy in the inductor and the three-phase coil and discharges the power module at the same time, because of the voltage dividing effect of the inductor and the three-phase coil, the power battery can be discharged after the step-down charging, and then the second discharging loop is turned on after the charging is completed, as shown in fig. 20, the second discharging loop is that the inductor L charges the power module, The power battery charging system comprises a seventh upper bridge diode VD7, a power utilization module, a lower bridge power switch (a second lower bridge diode VD2, a fourth lower bridge diode VD4 and a sixth lower bridge diode VD6) of a three-phase inverter 104 and a three-phase coil of a motor, when a second discharging loop is conducted, the inductor and the three-phase coil discharge the power utilization module simultaneously, and the power utilization module is discharged after the power battery is subjected to voltage reduction through the alternate conduction of a first energy storage loop and a first discharging loop.

An embodiment of the present application provides a vehicle, where the vehicle further includes the above-mentioned motor control circuit, the vehicle further includes a driving module and a heat exchange medium pipeline, the heat exchange medium pipeline is disposed on at least one of the power battery and the energy storage module, the three-phase inverter, and the three-phase ac motor, and the driving module is connected to the control module;

the control module controls the driving module to drive the heat exchange medium in the heat exchange medium pipeline to flow.

Specifically, as shown in fig. 21, the control module includes a vehicle control unit 301, a battery manager 302, a first motor controller 305, and a second motor controller 303, the vehicle control unit 301 is connected to the battery manager 302, the first motor controller 305, and the second motor controller 303 through a CAN bus, the dc charging pile is electrically connected to the first three-phase ac motor 306 through a connection line, the dc charging pile is electrically connected to the second three-phase ac motor 304 through a connection line 310, the power battery is electrically connected to the first motor controller 305 and the second motor controller 303, the cooling liquid tank 308, the water pump 309, the first three-phase ac motor 306, the first motor controller 305, the second three-phase ac motor 304, the second motor controller, and the power battery form a cooling liquid pipeline, the battery manager 302 is configured to collect power battery information including voltage, current, temperature, and the like, the motor controller is used for controlling power switches of an upper bridge and a lower bridge of the three-phase inverter and collecting three-phase current, and the vehicle controller is used for managing the operation of a whole vehicle and other controller devices on the vehicle. The battery manager 302 and the motor controller are communicated with the vehicle control unit 301 through a CAN (controller area network) line, when the vehicle control unit 301 obtains that the power battery needs to be heated, the water pump 309 is controlled to pump cooling liquid out of the cooling liquid tank 308, the cooling liquid sequentially passes through the first three-phase alternating current motor 306, the first motor controller 305, the second three-phase alternating current motor 304 and the second motor controller 303 to flow through the power battery, the vehicle control unit 3021 controls the first three-phase alternating current motor 306, the first motor controller 305, the second three-phase alternating current motor 304 and the second motor controller 303 to work so as to heat the cooling liquid, and further, when the cooling liquid flows through the power battery, the temperature of the power battery is increased.

Further, as shown in fig. 22, the three-phase ac motor 102 includes a motor shaft 125a, a stator assembly 127a, and a motor housing 123a, the motor shaft 125a is connected to the stator assembly 127a and the bearing seat 124a, the stator assembly 127a is disposed in the motor housing 123a, the motor housing 123a is provided with a heat exchange medium inlet 121a and a heat exchange medium outlet 126a through which the heat exchange medium 122a flows in and out, a heat exchange medium channel is disposed between the motor housing 123a and the stator assembly 127a, and the heat exchange medium channel is connected to the heat exchange medium inlet 121a and the heat exchange medium outlet 126 a.

The heat exchange medium channel may be provided between the motor housing 123a and the stator assembly 127a, and the heat exchange medium channel spirally surrounding the stator assembly 127a is provided in the motor housing 123 a.

According to the three-phase alternating current motor, the heat exchange medium channel is arranged between the motor shell 123a and the stator assembly 127a and is connected with the heat exchange medium inlet 121a and the heat exchange medium outlet 126a, so that heat generated by the motor can be effectively absorbed by heat exchange media in the heat exchange medium channel, the scheme does not need to arrange a channel inside the motor shaft 125a or the stator assembly 127a, the structural influence on the motor is small, the implementation mode is simple, and the cost is low.

The device comprises a power supply module, a three-phase inverter, a stator assembly, a battery cooling circuit, a stator assembly, a battery cooling circuit and a battery, wherein the three-phase inverter is controlled to enable the power supply module to alternately perform a charging process of a three-phase coil and a discharging process of the three-phase coil, so that the three-phase inverter and a three-phase alternating current motor heat a heat exchange medium flowing through at least one of the three-phase inverter and the three-phase alternating current motor through the electric driving cooling circuit, the heat exchange medium flows into a heat exchange medium inlet of the three-phase alternating current motor, the stator assembly heats the heat exchange medium in a heat exchange medium pipeline, and when the heated heat exchange medium flows through the battery cooling circuit to be heated, the temperature of the component to be heated is increased.

The application provides a vehicle, lead out the neutral conductor in three-phase AC motor, and then with power battery, boost module and three-phase inverter constitute different return circuits, provide the heat source through the inside three-phase coil of three-phase AC motor, three-phase inverter and boost module and inside device that generates heat, realize the heating to power battery through former cooling circuit behind the heating coolant liquid, need not use the engine or increase heating device just can realize promoting power battery's temperature, and heating efficiency is high, power battery temperature risees soon.

The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. A motor control circuit is characterized by comprising a boosting module, a first switch module, a three-phase inverter, a three-phase alternating current motor and a second switch module, the motor control circuit is connected with an external power supply module through the boosting module, the motor control circuit is connected with a power battery through the second switch module, the boost module is connected with the three-phase inverter and the second switch module through the first switch module, the three-phase inverter is connected between the three-phase alternating current motor and the second switch module, the boosting module is further connected with a midpoint of a three-phase coil connection of the three-phase alternating current motor, and the control module is respectively connected with the boosting module, the first switch module, the three-phase inverter, the three-phase alternating current motor, the second switch module and the power battery.

2. The motor control circuit according to claim 1, wherein a first end of the boost module is connected to a positive terminal of the external power supply module, a second end of the boost module is connected to a negative terminal of the external power supply module and a first end of the first switch module, a third end of the boost module is connected to a midpoint of a three-phase coil connection of the three-phase ac motor, the three-phase coil of the three-phase ac motor is connected to a three-phase arm of the three-phase inverter, the first end of the three-phase inverter is connected to a first terminal of the second switch module, the second end of the three-phase inverter is connected to a second terminal of the second switch module, and a third end and a fourth end of the second switch module are respectively connected to a positive terminal and a negative terminal of the power battery.

3. The motor control circuit of claim 1 wherein a first terminal of said boost module is connected to a positive terminal of said external power module and a first terminal of said first switch module, the second end of the voltage boosting module is connected with the negative pole end of the external power supply module and the second end of the first switch module, the third end of the boosting module is connected with the middle point of the three-phase coil connection of the three-phase alternating current motor, a three-phase coil of the three-phase alternating current motor is connected to a three-phase bridge arm of the three-phase inverter, a first end of the three-phase inverter is connected with a third end of the first switch module and a first end of the second switch module, a second terminal of the three-phase inverter is connected to the fourth terminal of the first switch module and the second terminal of the second switch module, and the third end and the fourth end of the second switch are respectively connected with the positive electrode end and the negative electrode end of the power battery.

4. The motor control circuit of claim 3 wherein the first switch module includes a first switch and a fifth switch, the first and second terminals of the fifth switch being the first and third terminals, respectively, of the first switch module, and the first and second terminals of the first switch being the second and fourth terminals, respectively, of the first switch module.

5. The motor control circuit according to claim 2 or 3, wherein the boost module includes an energy storage unit, a seventh power switch unit, and an eighth power switch unit, the first end of the energy storage unit is the third end of the boost module, the second end of the energy storage unit is connected to the output end of the seventh power switch unit and the input end of the eighth power switch unit, the input end of the seventh power switch unit is the first end of the boost module, and the output end of the eighth power switch unit is the second end of the boost module.

6. The motor control circuit of claim 2 or 3 wherein the second switch module comprises a third switch and a fourth switch, the first and second terminals of the third switch being the first and third terminals, respectively, of the second switch module, and the first and second terminals of the fourth switch being the second and fourth terminals, respectively, of the second switch module.

7. The motor control circuit of claim 2, wherein the external power module is a dc charging post;

or the external power supply module comprises an alternating current charging pile, a filter and a rectifier which are connected in sequence, and the rectifier is connected with the first end and the second end of the boosting module.

8. A heating method of a vehicle based on the motor control circuit of claim 1, characterized by comprising:

when the control module acquires that the component to be heated needs to be heated, the control module controls the first switch module, the second switch module, the boosting module and the three-phase inverter to alternately perform a charging process of the boosting module and a three-phase coil of the three-phase alternating current motor and a discharging process of the boosting module and the three-phase coil of the three-phase alternating current motor, so that the boosting module, the three-phase inverter and the three-phase alternating current motor heat a heat exchange medium flowing through at least one of the boosting module, the three-phase inverter and the three-phase alternating current motor.

9. The heating method according to claim 8, wherein the boost module comprises an energy storage unit, a seventh power switching unit, and an eighth power switching unit, the first switching module comprises a first switch and a fifth switch, the second switching module comprises a third switch and a fourth switch, a first end of the first switch is connected to an output end of the eighth power switching unit, a second end of the first switch is connected to an output end of the three-phase inverter and a first end of the fourth switch, a first end of the fifth switch is connected to an input end of the seventh power switching unit, and a second end of the fifth switch is connected to an input end of the three-phase inverter and a first end of the third switch;

the power battery, the third switch, the three-phase inverter, the three-phase alternating current motor, the energy storage unit, the eighth power switch unit, the first switch and the fourth switch form a first energy storage loop, and the energy storage unit, the eighth power switch unit, the first switch, the three-phase inverter and the three-phase alternating current motor form a first follow current loop;

the controlling the first switch module, the second switch module, the boost module, and the three-phase inverter to alternately perform a charging process of the boost module and a three-phase coil of the three-phase ac motor and a discharging process of the boost module and the three-phase coil of the three-phase ac motor by the power battery includes:

and controlling the first switch, the third switch, the fourth switch and the eighth power switch unit to be conducted, and controlling the three-phase inverter to enable the first energy storage loop and the first follow current loop to be conducted alternately.

10. The heating method according to claim 8, wherein the boost module comprises an energy storage unit, a seventh power switching unit, and an eighth power switching unit, the first switching module comprises a first switch and a fifth switch, the second switching module comprises a third switch and a fourth switch, a first end of the first switch is connected to an output end of the eighth power switching unit, a second end of the first switch is connected to an output end of the three-phase inverter and a first end of the fourth switch, a first end of the fifth switch is connected to an input end of the seventh power switching unit, and a second end of the fifth switch is connected to an input end of the three-phase inverter and a first end of the third switch;

the power battery, the third switch, the three-phase inverter, the three-phase alternating current motor, the energy storage unit, the eighth power switch unit, the first switch and the fourth switch form a first energy storage loop, and the energy storage unit, the seventh power switch unit, the fifth switch, the three-phase inverter and the three-phase alternating current motor form a second follow current loop;

the control module controls the first switch, the third switch, the fourth switch and the fifth switch to be conducted, and controls the three-phase inverter, the seventh power switch unit and the eighth power switch unit to enable the first energy storage loop and the second follow current loop to be conducted alternately.

11. A heating method of a vehicle based on the motor control circuit of claim 1, characterized by comprising:

when the control module is connected with an external power supply module and a component to be heated needs to be heated, the external power supply module controls the first switch module, the second switch module, the boosting module and the three-phase inverter to alternately perform a charging process of the boosting module and a three-phase coil of the three-phase alternating current motor and a discharging process of the boosting module and the three-phase coil of the three-phase alternating current motor, so that the boosting module, the three-phase inverter and the three-phase alternating current motor heat a heat exchange medium flowing through at least one of the boosting module, the three-phase inverter and the three-phase alternating current motor, and the second switch module comprises a third switch and a fourth switch.

12. The heating method according to claim 11, wherein the boost module comprises an energy storage unit, a seventh power switching unit, and an eighth power switching unit, the first switching module comprises a first switch and a fifth switch, a first end of the first switch is connected to an output end of the eighth power switching unit, a second end of the first switch is connected to an output end of the three-phase inverter and a first end of the third switch, a first end of the fifth switch is connected to an input end of the seventh power switching unit, and a second end of the fifth switch is connected to an input end of the three-phase inverter and a first end of the fourth switch;

the external power supply module, the seventh power switch unit, the energy storage unit, the three-phase alternating current motor, the three-phase inverter and the first switch form a third energy storage loop, and the energy storage unit, the three-phase alternating current motor, the three-phase inverter, the first switch and the eighth power switch unit form a third follow current loop;

the control module controls the second switch module to be turned off, the fifth switch to be turned off and the first switch to be turned on, and controls the three-phase inverter, the seventh power switch unit and the eighth power switch unit to enable the third energy storage loop and the third freewheeling loop to be alternately turned on.

13. The heating method according to claim 11, wherein the boost module comprises an energy storage unit, a seventh power switching unit, and an eighth power switching unit, the first switching module comprises a first switch and a fifth switch, a first end of the first switch is connected to an output end of the eighth power switching unit, a second end of the first switch is connected to an output end of the three-phase inverter and a first end of the fourth switch, a first end of the fifth switch is connected to an input end of the seventh power switching unit, and a second end of the fifth switch is connected to an input end of the three-phase inverter and a first end of the third switch;

the external power supply module, the seventh power switching unit, the energy storage unit, the three-phase alternating current motor, the three-phase inverter and the first switch form a third energy storage loop, and the energy storage unit, the three-phase alternating current motor, the three-phase inverter, the fifth switch and the seventh power switching unit form a fourth freewheeling loop;

the control module controls the second switch module to be switched off, the first switch to be switched on, the eighth power switch unit to be switched on and the eighth power switch unit to be switched off, and controls the three-phase inverter to enable the third energy storage loop and the fourth freewheeling loop to be switched on alternately.

14. A charging method of a vehicle based on the motor control circuit of claim 1, characterized by comprising:

acquiring the voltage of the external power supply module and the voltage of the power battery, and selecting a charging mode according to the voltage of the external power supply module and the voltage of the power battery, wherein the charging mode comprises boosting charging, voltage reduction charging and direct charging;

15. The charging method according to claim 14,

acquiring the voltage of the external power supply module and the voltage of the power battery, and selecting a charging mode according to the voltage of the external power supply module and the voltage of the power battery:

and controlling the first switch module, the second switch module, the boosting module and the three-phase inverter to alternately perform the charging process of the boosting module and the three-phase coil of the three-phase alternating current motor and the discharging process of the external power module, the boosting module and the three-phase coil of the three-phase alternating current motor on the power battery, so that the charging voltage of the external power module is boosted to exceed the voltage of the power battery and then the power battery is charged.

16. The charging method according to claim 15, wherein the boosting module includes an energy storage unit, a seventh power switching unit, and an eighth power switching unit, one end of the energy storage unit is connected to a midpoint of a three-phase coil connection of the three-phase ac motor, the other end of the energy storage unit is connected to an output terminal of the seventh power switching unit and an input terminal of the eighth power switching unit, an input terminal of the seventh power switching unit is connected to the external power supply module, and an output terminal of the eighth power switching unit is connected to the first switching module and the external power supply module;

the first switch module comprises a first switch and a fifth switch, the second switch module comprises a third switch and a fourth switch, a first end of the first switch is connected with the output end of the eighth power switch unit and the external power supply module, a second end of the first switch is connected with the output end of the three-phase inverter and the fourth switch, a first end of the fifth switch is connected with the input end of the seventh power switch unit and the external power supply module, and a second end of the fifth switch is connected with the input end of the three-phase inverter and the second switch module;

the external power supply module, the seventh power switch unit, the energy storage unit, the three-phase alternating current motor, the three-phase inverter and the first switch form a third energy storage loop, and the external power supply module, the seventh power switch unit, the energy storage unit, the three-phase alternating current motor, the three-phase inverter, the third switch, the power battery, the fourth switch and the first switch form a first charging loop;

the control module controls the third switch, the fourth switch, the fifth switch and the first switch to be switched on, and controls the three-phase inverter, the seventh power switch unit and the eighth power switch unit to enable the third energy storage loop and the first charging loop to be switched on alternately.

17. The charging method according to claim 14,

and controlling the first switch module, the second switch module, the boosting module and the three-phase inverter to alternately perform the discharging process of the boosting module, the three-phase coil of the three-phase alternating current motor and the power battery and the charging process of the boosting module and the three-phase coil of the three-phase alternating current motor and the power battery by the external power supply module, so that the charging voltage of the external power supply module is reduced and then the power battery is charged.

18. The charging method according to claim 17, wherein the boosting module includes an energy storage unit, a seventh power switching unit, and an eighth power switching unit, one end of the energy storage unit is connected to a middle point of a connection of three-phase coils of the three-phase ac motor, the other end of the energy storage unit is connected to an output terminal of the seventh power switching unit and an input terminal of the eighth power switching unit, an input terminal of the seventh power switching unit is connected to the external power supply module, and an output terminal of the eighth power switching unit is connected to the first switching module and the external power supply module;

the first switch module comprises a first switch and a fifth switch, the second switch module comprises a third switch and a fourth switch, a first end of the first switch is connected with an output end of the eighth power switch unit and the external power supply module, a second end of the first switch is connected with an output end of the three-phase inverter and the fourth switch, a first end of the fifth switch is connected with an input end of the seventh power switch unit and the external power supply module, and a second end of the fifth switch is connected with an input end of the three-phase inverter and the second switch module;

the external power supply module, the seventh power switch unit, the energy storage unit, the three-phase alternating current motor, the three-phase inverter and the first switch form a first energy storage charging loop, and the energy storage unit, the three-phase alternating current motor, the three-phase inverter, the third switch, the power battery, the fourth switch, the first switch and the eighth power switch unit form a second charging loop;

the control module controls the third switch, the fourth switch, the fifth switch and the first switch to be switched on, and controls the three-phase inverter, the seventh power switch unit and the eighth power switch unit to enable the first energy storage charging loop and the second energy storage charging loop to be alternately switched on.

19. A discharging method of a vehicle based on the motor control circuit of claim 1, wherein when the motor control circuit is connected to a power module, the discharging method comprises:

and controlling the first switch module, the second switch module, the three-phase inverter and the boost module to enable the power battery to output direct current, and enabling the power battery to discharge the electricity utilization module according to the selected charging mode.

20. The discharging method according to claim 19, wherein the selecting the discharging mode according to the voltage of the electricity utilization module and the voltage of the power battery comprises:

the control the boost module, the first switch module, the second switch module and the three-phase inverter to make the power battery alternately perform the energy storage module, the three-phase coil of the three-phase alternating current motor and the energy storage process of the power utilization module and the discharge process of the power battery, the energy storage module and the three-phase coil of the three-phase alternating current motor to the power utilization module so as to boost the discharge voltage of the power battery and then discharge the power supply module.

21. The discharge method according to claim 20, wherein the selecting the discharge mode according to the voltage of the electricity utilization module and the voltage of the power battery comprises:

22. A vehicle characterized by further comprising the motor control circuit of any one of claims 1 to 7.

23. The vehicle of claim 22, wherein the three-phase ac motor includes a motor shaft, a stator assembly, and a motor housing, the stator assembly is coupled to the motor shaft, the stator assembly is disposed in the motor housing, the motor housing has a heat exchange medium inlet and a heat exchange medium outlet, a heat exchange medium passage is disposed between the motor housing and the stator assembly, and the heat exchange medium passage is coupled to the heat exchange medium inlet and the heat exchange medium outlet.