CN111355430B

CN111355430B - Motor control circuit, charging and discharging method, heating method and vehicle

Info

Publication number: CN111355430B
Application number: CN201811574202.1A
Authority: CN
Inventors: 廉玉波; 凌和平; 潘华; 谢飞跃; 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: 2022-05-13
Anticipated expiration: 2038-12-21
Also published as: CN111355430A

Abstract

The application provides a motor control circuit, a charging and discharging method, a heating method and a vehicle, wherein the motor control circuit comprises a first switch module, a power switch module, a three-phase inverter, a three-phase alternating current motor, a second switch module and a control module. Meanwhile, a heating circuit is formed on the basis of charging, a heat source is provided by heating through a three-phase coil inside a three-phase alternating-current motor and an internal device of a three-phase inverter, heating of a part to be heated in a vehicle is realized through an original cooling loop after a heat exchange medium is heated, the temperature of the part to be heated can be increased without using an engine or adding a heating device, the heating efficiency is high, and the part to be heated is quickly heated.

Description

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

Technical Field

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

Background

Along with the development and rapid popularization of electric automobiles, the charging technology of the power battery of the electric automobile becomes more and more important, and the charging technology needs to meet the requirements of different users and the adaptability and compatibility of the power battery of the electric automobile and a charging pile.

At present, the direct current charging of the power battery is generally divided into a direct charging mode and a boosting charging mode, wherein the direct charging is that the positive electrode and the negative electrode of a charging pile are directly connected with the positive bus and the negative bus of the power battery through a contactor or a relay to directly charge the battery, and a boosting or voltage reducing circuit is not arranged in the middle; the step-up charging is that a DC/DC bridge circuit capable of bi-directionally increasing and decreasing voltage is additionally connected in parallel with a positive bus and a negative bus between a charging pile and a power battery. In general, low-temperature battery heating is to heat a cooling fluid in a battery cooling circuit at a low temperature by using a PTC heater or a heating wire heater, and heat a battery cell to a predetermined temperature by using the cooling fluid. In other schemes, an engine controller is used for controlling the engine to rotate at a constant speed at a certain rotating speed, the engine drives the generator to rotate, and the generator is used for rapidly charging and discharging the power battery unit to achieve the purpose of preheating the battery pack.

The engine is used for driving the generator to rotate to charge and discharge the battery for heating, the hybrid electric vehicle can only be applied to the hybrid electric vehicle, the engine and the generator can also generate certain noise, and the engine can also discharge polluted waste gas. For the existing boost charging circuit, a DC/DC bridge circuit, a corresponding control and acquisition circuit and the like need to be added independently, so that the product cost is increased; the same causes an increase in cost for heating the battery using the PTC heater, and the PTC heater, if damaged, causes an increase in secondary cost.

Disclosure of Invention

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

The present application is achieved in that the present application provides, in a first aspect, a motor control circuit comprising a first switch module, a power switch module, a three-phase inverter, a three-phase ac motor, a second switch module, and a control module, the three-phase inverter is connected with the power switch module in parallel, the three-phase inverter is also connected with a power battery through the second switch module, a three-phase bridge arm of the three-phase inverter is connected with a three-phase coil of the three-phase alternating current motor, a third end of the power switch module and a connection point of the three-phase coil of the three-phase alternating current motor form a charging port, the charging port is connected with an external power supply module through the first switch module, and the control module is respectively connected with the first switch module, the power switch module, the three-phase inverter, the three-phase alternating current motor and the second switch module.

In a second aspect, the present application provides a charging method for a power battery, based on the motor control circuit in the first aspect, the charging method includes:

acquiring a charging mode and an output type of the external power supply module, wherein the charging mode comprises boosting charging and direct charging, and the output type of the external power supply module comprises direct current or alternating current;

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

In a third aspect of the present application, a discharging method for a power battery is based on the motor control circuit of the first aspect, and the discharging method includes:

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

and controlling the first switch module, the second switch module, the three-phase inverter and the power switch 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 discharge mode.

The fourth aspect of the present application provides a heating method for a power battery, based on the motor control circuit of the first aspect, the heating method includes:

when the power battery needs to be heated, the first switch module is controlled to enable the external power supply module to output alternating current;

the first switching module, the power switching module, and the three-phase inverter are controlled such that a charging process of a three-phase coil of the three-phase ac motor and a discharging process of the three-phase coil of the three-phase ac motor by the external power supply module are alternately performed, so that the three-phase inverter and the three-phase ac motor heat a heat exchange medium flowing through at least one of the three-phase inverter and the three-phase ac motor. The fifth aspect of the present application provides a heating method for a power battery, based on the motor control circuit of the first aspect, the heating method includes:

when the temperature of the power battery is lower than a preset temperature value, controlling the first switch module and the second switch module to be conducted;

and controlling the power switch module and the three-phase inverter to enable the power battery to alternately perform a charging process on a three-phase coil of the three-phase alternating current motor and a discharging process on the three-phase coil of the three-phase alternating current motor, so that the three-phase inverter and the 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.

A sixth aspect of the present application provides a vehicle further including the power motor control circuit provided in the first aspect.

The application provides a motor control circuit, a charging method, a heating method and a vehicle, wherein the motor control circuit comprises a first switch module, a power switch module, a three-phase inverter, a three-phase alternating current motor, a second switch module and a control module, the three-phase inverter is connected with the power switch module in parallel, the three-phase inverter is further connected with a power battery through the second switch module, a three-phase bridge arm of the three-phase inverter is connected with a three-phase coil of the three-phase alternating current motor, a third end of the power switch module and a connection point of the three-phase coil of the three-phase alternating current motor form a charging port, the charging port is connected with an external power supply module through the first switch module, and the control module is respectively connected with the first switch module, the power switch module, the three-phase inverter, the three-phase alternating current motor and the second switch module. The technical scheme of the power supply module realizes that the power battery can be charged no matter the voltage of the power supply module is high or low, the compatibility and the adaptability are stronger, meanwhile, an external boosting or reducing circuit is not required to be additionally arranged, and the cost of an additional circuit is reduced. Meanwhile, a heating circuit is formed on the basis of charging, a heat source is provided by heating through a three-phase coil inside a three-phase alternating-current motor and an internal device of a three-phase inverter, heating of a part to be heated in a vehicle is realized through an original cooling loop after a heat exchange medium is heated, the temperature of the part to be heated can be increased without using an engine or adding a heating device, the heating efficiency is high, and the part to be heated is quickly heated.

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 a circuit diagram of a motor control circuit according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a motor control circuit according to a second embodiment of the present application;

fig. 5 is a circuit diagram of a motor control circuit according to a second embodiment of the present application;

fig. 6 is a schematic structural diagram of a motor control circuit according to a third embodiment of the present application;

fig. 7 is a circuit diagram of a motor control circuit according to a third embodiment of the present application;

fig. 8 is a schematic structural diagram of a motor control circuit according to a fourth embodiment of the present application;

fig. 9 is a circuit diagram of a motor control circuit according to a fourth embodiment of the present application;

fig. 10 is a circuit diagram of a motor control circuit provided in the fifth embodiment of the present application;

fig. 11 is a circuit diagram of a motor control circuit in a charging method for a power battery according to a sixth embodiment of the present application;

fig. 12 is a current path diagram of a first tank circuit in a charging method for a power battery according to a sixth embodiment of the present application;

fig. 13 is a current path diagram of a second tank circuit in a charging method for a power battery according to a sixth embodiment of the present application;

fig. 14 is a current path diagram of a first charging loop in a charging method for a power battery according to a sixth embodiment of the present application;

fig. 15 is a current path diagram of a first reverse energy storage loop in a charging method of a power battery according to a sixth embodiment of the present application;

fig. 16 is a current path diagram of a second reverse energy storage loop in a charging method of a power battery according to a sixth embodiment of the present application;

fig. 17 is a current path diagram of a first reverse charging loop in a charging method for a power battery according to a sixth embodiment of the present application;

fig. 18 is a current path diagram of a third tank circuit in a charging method for a power battery according to a sixth embodiment of the present application;

fig. 19 is a current path diagram of a third reverse energy storage loop in a charging method of a power battery according to a sixth embodiment of the present application;

fig. 20 is a circuit diagram of a motor control circuit in a discharging method of a power battery according to a seventh embodiment of the present application;

fig. 21 is a current path diagram of a motor control circuit in a discharging method of a power battery according to a seventh embodiment of the present application;

fig. 22 is another current path diagram of a motor control circuit in a discharging method of a power battery according to a seventh embodiment of the present application;

fig. 23 is another current path diagram of a motor control circuit in a discharging method of a power battery according to a seventh embodiment of the present application;

fig. 24 is another current path diagram of a motor control circuit in a discharging method of a power battery according to a seventh embodiment of the present application;

fig. 25 is a current path diagram of a first heating loop in a heating method for a power battery according to an eighth embodiment of the present application;

fig. 26 is a current path diagram of a second heating circuit in the heating method for the power battery according to the eighth embodiment of the present application;

fig. 27 is a current path diagram of a third heating circuit in the heating method for the power battery according to the eighth embodiment of the present application;

fig. 28 is a current path diagram of a fourth heating circuit in the heating method for a power battery according to the eighth embodiment of the present application;

fig. 29 is a current path diagram of a fifth heating loop in the heating method of the power battery according to the eighth embodiment of the present application;

fig. 30 is a current path diagram of a sixth heating loop in the heating method for the power battery according to the eighth embodiment of the present application;

fig. 31 is a current path diagram of a first heating energy storage loop in a heating method for a power battery according to a ninth embodiment of the present application;

fig. 32 is a current path diagram of a second heating energy storage loop in the heating method for the power battery according to the ninth embodiment of the present application;

fig. 33 is a current path diagram of a first freewheel loop in a heating method for a power battery according to a ninth embodiment of the present application;

fig. 34 is a current path diagram of a second freewheel loop in a heating method for a power battery according to a ninth embodiment of the present application;

fig. 35 is a current path diagram of a third freewheel loop in a heating method for a power battery according to a ninth embodiment of the present application;

fig. 36 is a current path diagram of a fourth freewheel loop in a heating method for a power battery according to a ninth 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 first switch module 102, a power switch module 103, a three-phase inverter 104, a three-phase ac motor 105, a second switch module 106, and a control module 108, where the three-phase inverter 104 is connected in parallel with the power switch module 103, the three-phase inverter 104 is further connected to a power battery 107 through the second switch module 106, a three-phase arm of the three-phase inverter 104 is connected to a three-phase coil of the three-phase ac motor 105, a connection point between a third end of the power switch module 103 and the three-phase coil of the three-phase ac motor 105 forms a charging port, the charging port is connected to an external power module 101 through the first switch module 102, the control module 108 is connected to the first switching module 102, the power switching module 103, the three-phase inverter 104, the three-phase ac motor 105, and the second switching module 106, respectively.

The external power module 101 may be a direct current provided by the direct current charging pile, an alternating current output by the alternating current charging pile, a 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 a range extender such as a power generator driven by an engine to generate electricity, a direct current rectified by a power generator controller, and the like; the first switch module 102 is used for connecting or disconnecting the external power supply module 101 to or from a circuit; the power switch module 103 comprises power switch units, the power switch units can be transistor, IGBT, MOS tube and other device types, the three-phase alternating current motor 105 comprises a three-phase coil, the three-phase coil is connected to a connection point, 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 point of the three-phase coil, the neutral line is connected with the first switch module 102 in series to form a connection circuit, the three-phase inverter 104 comprises six power switch units, the power switches can be transistor, IGBT, MOS tube and other device types, two power switch units form a phase bridge arm and form a three-phase bridge arm, and the connection point of the two power switch units in each phase bridge arm is connected with one phase coil in the three-phase alternating current motor 105; the second switch module 106 is configured to connect or disconnect the power battery 107 to or from a circuit, the control module 108 may collect voltage, current, and temperature of the power battery 107, phase current of the three-phase ac motor 105, and voltage of the external power supply module 101, the control module 108 may include a vehicle controller, a control circuit of a 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 power switch module 103 and the power switches in the three-phase inverter 104 to be turned on and off according to the acquired information, so as to achieve conduction of different current loops.

For the first switch module 102, in the first embodiment, a first end of the first switch module is connected to a third end of the power switch module in the charging port, and a second end of the first switch module is connected to the external power supply module; at this time, the first switch module may include only one switch.

For the first switch module 102, in the second embodiment, a first end of the first switch module is connected to a connection point of a three-phase coil of a three-phase alternating current motor in a charging port, and a second end of the first switch module is connected to an external power supply module; at this time, the first switch module may include only one switch.

For the first switch module 102, in the third embodiment, the first end of the first switch module is connected to the third end of the power switch module in the charging port, the second end of the first switch module is connected to the connection point of the three-phase coil of the three-phase ac motor in the charging port, and the third end and the fourth end of the first switch module are respectively connected to the positive electrode and the negative electrode of the external power supply module, and at this time, the first switch module may include two switches.

Further, the first switch module 102 includes a first switch and a second switch, the motor control circuit is connected to the external power supply module through a first end of the first switch and a first end of the second switch, a second end of the second switch forms a first end of the first switch module, and a second end of the first switch forms a second end of the first switch module.

Furthermore, the first switch module further comprises a fifth switch, and two ends of the fifth switch are respectively connected with the second end of the second switch and the second end of the first switch.

Further, the motor control circuit further comprises a rectifier switch, the positive end of the rectifier switch is connected with the second end of the three-phase inverter, and the first negative end and the second negative end of the rectifier switch are respectively connected with the first end and the second end of the first switch module.

The motor control circuit comprises a first energy storage module, the third end of the power switch module is connected with the first end of the first energy storage module, and the second end of the first energy storage module and the connection point of a three-phase coil of the three-phase alternating current motor form a charging port;

or the motor control circuit comprises a second energy storage module, a connection point of a three-phase coil of the three-phase alternating current motor is connected with a first end of the second energy storage module, and a third end of the power switch module and a second end of the second energy storage module form a charging port;

or the motor control circuit comprises a first energy storage module and a second energy storage module, the third end of the power switch module is connected with the first end of the first energy storage module, the connection point of a three-phase coil of the three-phase alternating current motor is connected with the first end of the second energy storage module, and the second end of the first energy storage module and the second end of the second energy storage module form a charging port.

For the power switch module, as shown in fig. 2, the power switch module includes a seventh power switch unit and an eighth power switch unit, the seventh power switch unit and the eighth power switch unit are respectively connected to the three-phase inverter 105, and a common junction of the seventh power switch unit and the eighth power switch unit is connected to the first switch module.

As for the connection relationship between the first switch module and the power switch module, as a first implementation, the first switch module includes a first switch and a second switch; the power switch module comprises a seventh power switch unit and an eighth power switch unit which form a bridge arm and are connected in series; the three-phase inverter comprises a first power switch unit, a fourth power switch unit, a third power switch unit, a sixth power switch unit, a fifth power switch and a second power switch, wherein the first power switch unit and the fourth power switch unit are connected in series to form a three-phase bridge arm; the second end of the first switch is connected between the seventh power switch unit and the eighth power switch unit.

The seventh power switch unit and the eighth power switch unit may be of transistor, IGBT, MOS transistor, etc., and two power switch units form a phase bridge arm, and output PWM signals to the seventh power switch unit and the eighth power switch unit through the control module 108 to turn on or off the seventh power switch unit or the eighth power switch unit, so as to form different current loops with the external power module 101, the three-phase inverter 104, the three-phase ac motor 105, and the power battery 107, thereby realizing charging of the rechargeable battery by the external power module 101, and feeding energy of the rechargeable battery back to the power grid or other electric devices, vehicles, etc., and taking electricity from the external power module 101 for heating and taking electricity from the rechargeable battery for heating.

As for the connection relationship between the first switch module and the power switch module, as a second implementation manner, the first switch module includes a fifth switch and a first/second switch, the first/second switch includes a first switch and a second switch, and the first switch, the fifth switch and the second switch are connected in series; the power switch module comprises a seventh power switch unit and an eighth power switch unit which form a bridge arm and are connected in series; the three-phase inverter comprises a first power switch unit, a fourth power switch unit, a third power switch unit, a sixth power switch unit, a fifth power switch and a second power switch, wherein the first power switch unit and the fourth power switch unit are connected in series to form a three-phase bridge arm; the connection point of the first switch and the fifth switch is connected with the connection point of the seventh power switch unit and the eighth power switch unit, and the connection point of the fifth switch and the second switch is connected with the connection point of the three-phase coil of the three-phase alternating current motor.

Further, in the second embodiment, the motor control circuit further includes an energy storage module, the energy storage module includes at least one of a first energy storage device and a second energy storage device, wherein the first energy storage device is disposed between a connection point of the second switch and the fifth switch and a connection point of the seventh power switch unit and the eighth power switch unit; the second energy storage device is arranged between a connection point of the first switch and the fifth switch and a connection point of a three-phase coil of the three-phase alternating current motor.

Furthermore, the motor control circuit further comprises a rectifier switch, the rectifier switch comprises a first diode and a second diode, the anode of the first diode, the anode of the second diode, the output end of the eighth power switch unit, the output end of the fourth power switch unit, the output end of the sixth power switch unit and the output end of the second power switch unit are connected, the cathode of the first diode is connected with the connection point of the second switch and the fifth switch, and the cathode of the second diode is connected with the connection point of the first switch and the fifth switch.

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, output ends of the first power switch unit, the third power switch unit, and the fifth power switch unit are connected in common and connected to a seventh power switch unit and a second switch module 106 in the power switch module 103, output ends of the second power switch unit, the fourth power switch unit, and the sixth power switch unit are connected in common and connected to an eighth power switch unit and a second switch module 106 in the power switch module 103, a first-phase coil of the three-phase ac motor 105 is connected to an input end of the first power switch unit and an input end of the fourth power switch unit, a second-phase coil of the three-phase alternating current motor 105 is connected to the input terminal of the third power switching unit and the input terminal of the sixth power switching unit, and a third-phase coil of the three-phase alternating current motor 105 is connected to the input terminal of the fifth power switching unit and the input terminal of the second power switching unit.

The first power switch unit and the fourth power switch unit in the three-phase inverter 104 form an a-phase bridge arm, the third power switch unit and the sixth power switch unit form a B-phase bridge arm, the input end of the fifth power switch unit and the second power switch unit form a C-phase bridge arm, and the control mode of the three-phase inverter 104 may be any one of the following or a combination of several of the following: if any one or any two of A, B, C three-phase bridge arms and three bridge arms can be realized, 7 control heating modes are realized, and the method is flexible and simple. The switching of the bridge arms can be beneficial to realizing the large, medium and small selection of heating power, 1, 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 alone first, a first power switch unit and a fourth power switch unit are controlled to heat for a period of time, then a B phase bridge arm works alone, 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 alone, 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 circulated to be electrified and heated in turn; 2. 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 to control a first power switch unit, a fourth power switch unit, a third power switch unit and a sixth power switch unit to heat for a period of time, then a BC-phase bridge arm works to control a third power switch unit, a sixth power switch unit and a second power switch unit to heat for the same time, then a CA-phase bridge arm works to control a fifth power switch unit, a second power switch unit, a first power switch unit and a fourth power switch unit to heat for the same time, and then the AB-phase bridge arm works, and the steps are repeated to realize the three-phase inverter 104; 3. preferably, the three-phase bridge arm power switches can be selected to be controlled simultaneously, namely, the three-phase upper bridge arm is switched on simultaneously, and the three-phase lower bridge arm is switched off simultaneously; and the three-phase upper bridge arm is turned off at the same time, the three-phase lower bridge arm is turned on at the same time, the three-phase power bridge arm is equivalent to a single DC/DC, and the three-phase loops are balanced theoretically, so that three-phase currents are balanced, the three-phase inverter 104 and the three-phase coil are heated and balanced, the 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 windings, so that the stator magnetic field is basically zero, and the motor is basically free from torque generation, thereby being beneficial to greatly reducing the stress of a transmission system.

Fig. 3 is a circuit diagram of an example of a motor control circuit provided in an embodiment of the present application, in which only an external power module 101, a power switch module 103, a power battery 107, a three-phase inverter 104, and a three-phase ac motor 105 are considered for convenience of description of the motor control circuit, and other electrical devices are omitted from the upper diagram, a first switch module 102 includes a switch K1 and a switch K2, a second switch module 106 includes a switch K3 and a switch K4, the power switch module 103 includes 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 8, a first power switch unit in the three-phase inverter 104 includes a first upper bridge arm VT1 and a first upper bridge diode VD1, a second power switch unit includes a second lower bridge arm 2 and a second lower bridge diode VD2, the third power switch unit includes a third upper bridge arm VT3 and a third upper bridge diode VD3, the fourth power switch unit includes a fourth lower bridge arm VT4 and a fourth lower bridge diode VD4, the fifth power switch unit includes a fifth upper bridge arm VT5 and a fifth upper bridge diode VD5, the sixth power switch unit includes a sixth lower bridge arm VT6 and a sixth lower bridge diode VD6, the three-phase ac motor 105 is a three-phase four-wire system, and may be a permanent magnet synchronous motor or an asynchronous motor, a neutral line is drawn from a connection midpoint of a three-phase coil, and the neutral line is connected to the switch K1, and three-phase coils of the motor are respectively connected to upper and lower bridge arms A, B, C in the three-phase inverter 104, wherein a specific control method for the control module 108 refers to the following embodiments.

As a second embodiment, as shown in fig. 4 and fig. 5, the motor control circuit further includes a first energy storage module 109, and the first energy storage module 109 is connected between the first switching module 102 and the power switching module 103, where the first energy storage module 109 is an inductor L1.

As a third embodiment, as shown in fig. 6 and 7, the motor control circuit further includes a second energy storage module 110, and the second energy storage module 110 is connected between the first switching module 102 and the three-phase ac motor 105, where the second energy storage module 109 is an inductor L2.

As a fourth embodiment, as shown in fig. 8 and 9, the motor control circuit further includes a first energy storage module 109 and a second energy storage module 110, where the first energy storage module 109 is connected between the first switch module 102 and the power switch module 103, and the second energy storage module 110 is connected between the first switch module 102 and the three-phase ac motor 105, where the first energy storage module 109 is an inductor L1, and the second energy storage module 109 is an inductor L2.

The difference between the second embodiment and the fourth embodiment and the first embodiment is that an energy storage module is added, and the function of the energy storage module is the same as that of the three-phase coil of the three-phase ac motor 105, and the energy storage module participates in energy storage in the charging circuit and starts to discharge in the discharging circuit.

As an embodiment fifth, as shown in fig. 10, the motor control circuit further includes a rectifier switch 120, the rectifier switch 120 includes a first diode VD9 and a second diode VD10, an anode of the first diode VD9, an anode of the second diode VD10, an output terminal of the eighth power switch unit, an output terminal of the fourth power switch unit, and an output terminal of the sixth power switch unit are connected to an output terminal of the second power switch unit, a cathode of the first diode VD9 is connected to a connection point of the second switch and the fifth switch, and a cathode of the second diode VD10 is connected to a connection point of the first switch and the fifth switch.

The sixth embodiment of the present application provides a charging method for a power battery, where based on a motor control circuit provided in the first embodiment, the charging method provided in the sixth embodiment is used to charge a power battery 107 by an external power supply module 101, and the charging method includes:

acquiring a charging mode and an output type of an external power supply module, wherein the charging mode comprises boosting charging and direct charging, and the output type of the external power supply module comprises direct current or alternating current;

In the above steps, the execution main body is the control module 108, when the control module 108 acquires that the external power module 101 is connected to the circuit, for example, when a charging gun is plugged into a dc charging post interface, the control module 108 acquires a charging mode and an output type of the external power module, the charging mode includes boost charging and direct charging, the output type of the external power module includes dc or ac, wherein when the output type of the external power module is dc, the charging mode is selected according to the voltage of the external power module 101 and the voltage of the power battery 107, different charging modes are selected according to the comparison result to charge the power battery 107, when the voltage of the external power module 101 is lower than the voltage of the power battery 107, the power battery 107 can be charged by using the dc boost charging mode, and since the three-phase coil of the three-phase ac motor 105 can store electric energy, the first switch module 102 and the second switch module 106 can be controlled to be conducted, the external power supply module 101 can be controlled to charge the three-phase coil of the three-phase alternating-current motor 105 by controlling the power switch module 103 and the three-phase inverter 104, then the external power supply module 101 and the three-phase coil of the three-phase alternating-current motor 105 can discharge the power battery 107, and in the discharging process, as the three-phase coil of the three-phase alternating-current motor 105 also outputs voltage at the moment, the voltage output by the external power supply module 101 and the voltage output by the three-phase coil are superposed to boost the voltage of the external power supply module 101, so that the normal charging of the power battery 107 can be realized; when the control module 108 acquires that the maximum voltage which can be output by the external power supply module 101 is higher than the voltage of the power battery 107, the first switch module 102 and the second switch module 106 are controlled to be switched on, so that the external power supply module 101 directly charges the power battery 107; when the output type of the external power supply module is ac, in the first half cycle of the output ac of the external power supply module 101, the external power supply module 101 inputs current to the power module and stores and charges the three-phase ac motor 105, and then charges the power battery 107, and in the second half cycle of the output ac of the external power supply module 101, the external power supply module 101 inputs current to the three-phase ac motor 105 and stores and charges the three-phase ac motor 105, and then charges the power battery 107. This application embodiment draws forth the neutral conductor in three-phase AC motor 105, and then constitute different charge-discharge circuit with power battery 107 and three-phase inverter 104, when obtaining that the highest output voltage of external power source module 101 is less than power battery 107 voltage through control module 108, adopt original three-phase AC motor 105 to boost the voltage of external power source module 101 and then charge for power battery 107, when control module 108 obtains that the highest output voltage of external power source module 101 is not less than power battery 107 voltage, directly charge power battery 107, no matter the voltage height of external power source module 101 has been realized, can charge for power battery 107, and compatible adaptability is stronger, need not additionally increase outside boost or step-down circuit simultaneously, the cost of additional circuit has been reduced.

Further, when the boost charging mode is selected when the voltage of the external power supply module 101 is lower than the voltage of the power battery 107, the power switch module 103 and the three-phase inverter 104 are controlled to alternately perform the charging process of the external power supply module 101 on the three-phase coil of the three-phase ac motor 105 and the discharging process of the external power supply module 101 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 boosted and then the power battery 107 is charged.

The charging process of 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 and the three-phase coil of the three-phase alternating current motor 105 are controlled to be alternately performed, so that the energy storage module and the three-phase coil of the three-phase alternating current motor 105 output voltage after storing electric energy and are superposed with the voltage output by the external power supply module 101, the voltage of the external power supply module 101 is boosted, and the power battery 107 can be normally charged by the external power supply module 101.

In one embodiment, the power switch module 103 includes a seventh power switch unit and an eighth power switch unit, the external power supply module 101, the first switch module 102, the eighth power switch unit, the three-phase inverter 104, and the three-phase ac motor 105 form a first energy storage circuit, and the external power supply module 101, the first switch module 102, the seventh power switch unit, the second switch module 106, the power battery 107, the three-phase inverter 104, and the three-phase ac motor 105 form a first charging circuit.

Make the charging process of external power module to the three-phase coil of three-phase alternating current motor and the discharging process of external power module and three-phase coil of three-phase alternating current motor to power battery go on in turn, include:

and controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter 104 to enable the first energy storage loop and the first charging loop to be conducted alternately.

In another embodiment, the power switch module 103 includes a seventh power switch unit and an eighth power switch unit, the external power supply module 101, the first switch module 102, the seventh power switch unit, the three-phase inverter 104, and the three-phase ac motor 105 form a second tank circuit, and the external power supply module 101, the first switch module 102, the eighth power switch unit, the second switch module 106, the power battery 107, the three-phase inverter 104, and the three-phase ac motor 105 form a first charging circuit.

The method for alternately performing the charging process of the external power supply module 101 on the three-phase coil of the three-phase alternating current motor 105 and the discharging process of the external power supply module 101 and the three-phase coil of the three-phase alternating current motor 105 on the power battery 107 comprises the following steps:

and the second energy storage loop and the first charging loop are alternatively conducted by controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter.

The external power supply module 101, the first switch module 102, the seventh power switch unit, the three-phase inverter 104, the three-phase alternating current motor, the power battery 107 and the second switch module form a first reverse charging loop.

The control module 108 controls the first switch module 102 and the second switch module 106 to be turned on, detects that the external power module 101 outputs direct current, and outputs PWM control signals to the three-phase inverter 104 and the power switch module 103 to enable the external power module 101 to charge the first energy storage loop or the second energy storage loop, so that the first energy storage loop or the second energy storage loop forms an inductive energy storage loop, and then controls the first charging loop to be turned on, and the three-phase ac motor 105 outputs current to enable the first charging loop to form a current follow current loop, that is, in the process of alternately turning on the first energy storage loop or the second energy storage loop and the first charging loop, the three-phase inverter 104 and the three-phase ac motor 105 are firstly in a charging state and then in a discharging state.

When the external power supply module 101 is detected to output alternating current, the first half cycle of the alternating current output by the external power supply module 101 controls the power switch module 103 and the switch of the three-phase inverter 104 to be switched on and off, the first energy storage loop or the second energy storage loop is charged by the external power supply module 101 from top to bottom, so that the first energy storage loop or the second energy storage loop forms an inductive energy storage loop, the first charging loop is switched on, and the three-phase alternating current motor 105 outputs current, so that the first charging loop forms a current follow current loop, namely, in the process of alternately switching on the first energy storage loop or the second energy storage loop and the first charging loop, the three-phase inverter 104 and the three-phase motor 105 are firstly in a charging state and then in an alternating current discharging state; the external power module 101 controls the switches of the power switch module 103 and the three-phase inverter 104 to be turned on and off in the latter half cycle of the output alternating current, the external power module 101 charges the first energy storage loop or the second energy storage loop in the up-down direction and the up-down direction in the reverse direction, so that the first energy storage loop or the second energy storage loop forms an inductive energy storage loop, and then the first reverse charging loop is turned on, in this embodiment, by setting the first switch module 102 and the second switch module 106 to be turned on, when the external power supply outputs direct current or alternating current, the external power supply module 101, the three-phase inverter 104, the three-phase alternating current motor 105 and the power battery 107 are formed into a charge and discharge circuit, and the first energy storage loop and the first charging loop are alternatively conducted by controlling the power switch units in the power switch module 103 and the three-phase inverter 104, so that the external power supply module 101 can boost and charge the power battery 107.

The charging method in the sixth embodiment may also be applied to the motor control circuit provided in the second to fifth embodiments, and the charging method includes:

Further, the method for selecting the charging mode according to the voltage of the external power supply module and the voltage of the power battery comprises the following steps:

and selecting a boosting charging mode when the highest output voltage of the external power supply module is acquired to be lower than the voltage of the power battery.

Controlling the power switch module and the three-phase inverter to enable the external power supply module to charge the power battery according to the selected charging mode, and the method comprises the following steps:

and controlling the power switch module and the three-phase inverter to alternately perform the charging process of the energy storage module and the three-phase coil of the three-phase alternating current motor by the external power supply module and the discharging process of the power battery by the external power supply module, the energy storage module and the three-phase coil of the three-phase alternating current motor so as to boost the charging voltage of the external power supply module and then charge the power battery.

The energy storage module is additionally arranged in the motor control circuit, so that the PFC can be corrected and controlled by power in the process of charging the power battery by the external power supply module, and the harmonic wave of a power grid is reduced.

The following describes the technical solution of the embodiment of the present application in detail through a specific circuit structure:

fig. 11 is a circuit diagram of an example of a motor control circuit provided in an embodiment of the present application, and as shown in fig. 12, an external power supply module 101, a switch K2, an inductor L, an eighth lower bridge arm VT8, a lower bridge power switch of a three-phase inverter 104 (a second lower bridge diode VD2, a fourth lower bridge diode VD4, a sixth lower bridge diode VD6), a three-phase ac motor 105, and a switch K1 form a first energy storage loop.

As shown in fig. 13, the external power supply module 101, the switch K2, the inductor L, the seventh upper bridge diode VD7, the upper bridge power switches (the first upper bridge arm VT1, the third upper bridge arm VT3, and the fifth upper bridge arm VT5) of the three-phase inverter 104, the three-phase ac motor 105, and the switch K1 form a second tank circuit.

As shown in fig. 14, the external power supply module 101 discharges, and current passes through a first charging loop formed by the positive electrode of the external power supply module 101, the switch K2, the inductor L, the seventh upper bridge diode VD7, the switch K3, the power battery 107, the switch K4, the lower bridge power switch of the three-phase inverter 104 (the second lower bridge diode VD2, the fourth lower bridge diode VD4, and the sixth lower bridge diode VD6), the three-phase ac motor 105, and the switch K1.

In the above figure, other electrical devices are omitted, only the external power supply module 101, the power switch module 103, the power battery 107, the three-phase inverter 104 and the three-phase ac motor 105 are considered, and when the maximum voltage output by the external power supply module 101 is lower than the voltage of the power battery 107, the control step of the control module 108 specifically includes:

step 1, when the direct current charging gun is inserted into the direct current charging pile interface, the battery manager acquires the temperature of the power battery 107.

And step 2, judging whether the current temperature of the power battery 107 is lower than a preset temperature.

And 3, if the temperature of the power battery 107 is lower than the preset temperature, entering a power battery 107 heating program to heat the temperature of the power battery 107 to be higher than the preset temperature.

And 4, if the current temperature of the power battery 107 is higher than the preset temperature, acquiring the voltage Uin of the direct current charging pile and the voltage Udc of the power battery 107, and judging the voltage of the two.

And 5, when Uin is less than Udcmin, considering that the voltage of the direct current charging pile is lower than the voltage of the battery, and charging the battery by adopting a direct current boosting charging mode.

Step 6, as shown in fig. 12 or 13, the battery manager controls the switch K1, the switch K2, the switch K3, and the switch K4 to be turned on, the motor controller outputs the first half cycle of the PWM signal to turn on the eighth lower arm VT8, the external power supply module 101 discharges to turn on the first energy storage loop, or the motor controller outputs the first half cycle of the PWM signal to turn on the first upper arm VT1, the third upper arm VT3, and the fifth upper arm VT5 to turn on the second energy storage loop, the external power supply module 101 charges the inductor L and the three-phase coil of the motor, at this time, the three-phase coils are turned on simultaneously, the current increases simultaneously, the inductor starts to store energy, at this time, the left end of the inductor voltage is positive, and the right end is negative.

Step 7, as shown in the graph 13, the battery manager controls the switch K1, the switch K2, the switch K3, and the switch K4 to be turned on, the motor controller outputs a second half cycle of the PWM signal to turn on the seventh upper bridge arm VT7, the external power module 101 discharges, a current passes through a first charging loop formed by the anode of the external power module 101, the switch K2, the inductor L, the seventh upper bridge diode VD7, the switch K3, the power battery 107, the switch K4, and the lower bridge power switches (the second lower bridge diode VD2, the fourth lower bridge diode VD4, the sixth lower bridge diode VD6) of the three-phase inverter 104, and the switch K1, at this time, the current in the three-phase coil flows through the three-phase lower bridge diodes at the same time, the inductor starts to discharge, the current is simultaneously reduced, and the voltage of the inductor and the voltage of the three-phase coil are superimposed on the dc charging pile, so as to boost the battery to charge the battery.

And 9, the battery manager acquires the battery charging current, when the current is smaller than the current value corresponding to the required charging power, the motor controller adjusts and increases the PWM conduction duty ratio, when the current is larger than the current value corresponding to the required charging power, the motor controller adjusts and decreases the PWM conduction duty ratio until the charging power is met, and meanwhile, the three-phase current of the motor is acquired, so that overcurrent and overtemperature control is facilitated.

And 10, repeating the steps 2-4 before the battery is fully charged, and if the battery is fully charged, turning off 6 power switches of the three-phase inverter 104 by the motor controller and turning off switches K1, K2, K3 and K4 by the battery manager.

In another example, as shown in fig. 15, the external power supply module 101, the switch K1, the three-phase ac motor 105, 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, the eighth lower bridge diode VD8, the inductor L, and the switch K2 form a first reverse energy storage loop.

As shown in fig. 16, the external power supply module 101, the switch K1, the three-phase ac motor 105, the upper bridge power switch (the first upper bridge diode VD1, the third upper bridge diode VD3, and the fifth upper bridge diode VD5) of the three-phase inverter 104, the seventh upper bridge arm VT7, the inductor L, and the switch K2 form a second reverse energy storage loop.

As shown in fig. 17, the external power supply module 101 discharges, and current passes through a first reverse charging loop formed by the positive electrode of the external power supply module 101, the switch K1, the three-phase ac motor 105, the upper bridge power switches (the first upper bridge diode VD1, the third upper bridge diode VD3, and the fifth upper bridge diode VD5) of the three-phase inverter 104, the switch K3, the power battery 107, the switch K4, the eighth lower bridge diode VD8, and the inductor L.

When the external power supply module 101 outputs alternating current, the switches K1, K2, K3 and K4 are controlled to be closed, and when it is obtained that the voltage output by the external power supply module 101 is positive, negative and positive, the eighth lower bridge arm VT8 or the first upper bridge arm VT1, the third upper bridge arm VT3 and the fifth upper bridge arm VT5 are controlled to be switched on, so that the first energy storage loop (shown in fig. 12) or the second energy storage loop (shown in fig. 13) is switched on to store energy for the inductance L and the inductance of the three-phase alternating current motor 105; the first charging loop (shown in fig. 14) is controlled to be conducted by controlling the eighth lower bridge arm VT8 and simultaneously controlling the first upper bridge arm VT1, the third upper bridge arm VT3 and the fifth upper bridge arm VT5 to be simultaneously turned off; when the voltage of the external power supply module 101 is acquired to be positive, negative and positive, the first reverse energy storage loop (shown in fig. 15) or the second reverse energy storage loop (shown in fig. 16) is conducted to store energy for the inductor L and the inductor of the three-phase alternating-current motor 105 by controlling the seventh upper bridge arm VT7 or simultaneously controlling the second lower bridge arm VT2, the fourth lower bridge arm VT4 and the sixth lower bridge arm VT6 to be conducted; the voltage of the charging pile, the inductance L and the discharge voltage of the inductance of the three-phase alternating current motor 105 are connected in series to be larger than the voltage of the power battery 107 by controlling the VT7 and simultaneously controlling the second lower bridge arm VT2, the fourth lower bridge arm VT4 and the sixth lower bridge arm VT6 to be switched off and switched on, the voltage boosting charging is realized by controlling the switching-on and switching-off of a rectifier switch through the PWM wave of a switch, the cyclic switching-on and switching-off of a power device are controlled by controlling the PWM duty ratio signal of the power device to be modulated according to the amplitude variation of the voltage of the power grid, and the current of the power grid is enabled to realize the unit Power Factor Control (PFC) along with the voltage of the power grid. Therefore, when the voltage of the power battery 107 is higher than the output voltage of the charging pile, the power battery 107 can be boosted and charged.

In another example, as shown in fig. 18, the external power supply module 101, the switch K2, the inductor L, the eighth lower arm VT8, the capacitor C, the upper bridge power switches of the three-phase inverter 104 (the first upper arm VT1, the third upper arm VT3, and the fifth upper arm VT5), the three-phase ac motor 105, and the switch K1 form a third energy storage loop.

As shown in fig. 19, the external power supply module 101, the switch K1, the three-phase ac motor 105, and 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, the capacitor C, the seventh upper bridge arm VT7, the inductor L, and the switch K2 form a third reverse energy storage loop.

When the external power supply module 101 outputs alternating current, the control switches K1, K2, K3 and K4 are closed, the third energy storage circuit (fig. 18) and the first charging circuit (fig. 14) are controlled to be alternately conducted when the voltage output by the external power supply module 101 is acquired to be positive up and negative down, and the third reverse energy storage circuit (fig. 19) and the first reverse charging circuit (fig. 17) are controlled to be alternately conducted when the voltage output by the external power supply module 101 is acquired to be positive up and negative down.

The seventh embodiment of the present application provides a discharge method of a power battery, where based on the motor control circuit of the first embodiment, the discharge method provided by the seventh embodiment is used to implement discharge of the power battery to an electricity-using module, and the discharge method includes:

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

The seventh embodiment of the present application is different from the sixth embodiment in that the sixth embodiment is used to charge the power battery 107 by the external power module 101, and the seventh embodiment is used to discharge the power module 121 by the power battery 107, except that the power battery 107 can directly discharge the power module 121, and the power battery 107 drops the voltage to discharge the power module 121.

When the control module 108 acquires that the power utilization module 121 is connected to the circuit, for example, when the battery is plugged into the dc charging pile interface, the control module 108 compares the voltage of the power battery 107 with the voltage of the power utilization module 121, and selects different discharging modes to discharge the power utilization module 121 according to the comparison result, when the control module 108 acquires that the voltage of the power battery 107 is higher than the voltage of the power utilization module 121, the control module 108 controls the first switch module 102, the second switch module 106, the power switch module 103 and the three-phase inverter 104 to discharge the power battery 107 to the three-phase ac motor 105 and the power utilization module 121, and discharges the battery of the power battery 107 through the three-phase ac motor 105 ac, and due to the voltage division effect of the three-phase ac motor 105 during the discharging process, and the voltage of the three-phase ac motor 105 is lower than the voltage of the power battery 107 during the discharging process, the discharging of the electricity utilization module 121 after the output voltage of the power battery 107 is reduced can be realized, a neutral line is led out from the three-phase alternating-current motor 105 in the embodiment of the application, and then different loops are formed with the power battery 107, the power switch module 103 and the three-phase inverter 104, and when the control module 108 acquires that the voltage of the power battery 107 is higher than the voltage of the electricity utilization module 121, the original three-phase alternating-current motor 105 is adopted to reduce the voltage of the power battery 107 and then discharge the electricity utilization module 121.

Further, the method for selecting the discharge mode according to the voltage of the electricity utilization module and the voltage of the power battery comprises the following steps:

when the obtained voltage of the power battery is higher than the voltage of the power utilization module, a voltage reduction discharge mode is selected;

controlling the power switch module and the three-phase inverter to enable the power battery to discharge the power utilization module according to the selected discharge mode, and the method comprises the following steps:

and controlling the power switch module and the three-phase inverter to alternately perform the discharging process of the three-phase coil of the three-phase alternating current motor by the power battery and the discharging process of the three-phase coil of the three-phase alternating current motor to the power utilization module so as to discharge the power utilization module after the voltage of the power battery is reduced.

As an embodiment, the power switch module 103 includes a seventh power switch unit and an eighth power switch unit, the power battery 107, the second switch module 106, the seventh power switch unit, the first switch module 102, the power utilization module 121, the three-phase ac motor 105 and the three-phase inverter 104 form a first discharge energy storage loop, and the three-phase ac motor 105, the three-phase inverter 104, the eighth power switch unit, the first switch module 102 and the power utilization module 121 form a first discharge loop;

alternately performing a charging process of the three-phase coil of the three-phase ac motor 105 by the power battery 107 and a discharging process of the electricity utilization module 121 by the three-phase coil of the three-phase ac motor 105 includes:

and controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter 104 to make the first discharging energy storage loop and the first discharging loop alternately conducted.

In another embodiment, the power switch module 103 includes a seventh power switch unit and an eighth power switch unit, the power battery 107, the second switch module 106, the three-phase inverter 104, the three-phase ac motor 105, the power utilization module 121, the first switch module 102, and the eighth power switch unit form a second discharge energy storage loop, and the three-phase ac motor 105, the three-phase inverter 104, the seventh power switch unit, the first switch module 102, and the power utilization module 121 form a second discharge loop;

alternating a charging process of the three-phase coil of the three-phase ac motor 105 by the power battery 107 and a discharging process of the three-phase coil of the three-phase ac motor 105 to the external power supply module 101 includes:

and controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter 104 to enable the second discharging energy storage loop and the second discharging loop to be conducted alternately.

The discharging method in the seventh embodiment can also be applied to the motor control circuits provided in the second to fifth embodiments.

Fig. 20 is a circuit diagram of an example of a motor control circuit provided in an embodiment of the present application, in which other electrical devices are omitted from the upper diagram for convenience of description of the motor control circuit, only the electricity utilization module 121, the power switch module 103, the power battery 107, the three-phase inverter 104, and the three-phase ac motor 105 are considered, and when the voltage of the electricity utilization module 121 is lower than the voltage of the power battery 107, the control steps of the control module 108 specifically include:

the electric energy in the power battery 107 is converted into alternating current to be fed back to a power grid or to other electric equipment through the charging interface, or is directly converted into direct current to be used by other electric equipment, and the implementation process is as follows:

as shown in fig. 21, the switches K1, K2, K3 and K4 are controlled to be closed, when the power battery 107 needs to be discharged, the output positive and negative voltages are selected to control the switches of the four-phase bridge arm, when the charging interface needs to output direct current with positive and negative upper and lower, the seventh upper bridge arm VT7, the second lower bridge arm VT2, the fourth lower bridge arm VT4 and the sixth lower bridge arm VT6 are controlled to be simultaneously turned on, the current of the power battery 107 flows through the external equipment connected with the seventh upper bridge arm VT7, the inductor L and the charging interface and the inductance of the three-phase alternating current motor 105, flows back to the power battery 107 through the second lower bridge arm VT2, the fourth lower bridge arm VT4 and the sixth lower bridge arm VT6, and stores the energy in the inductor L and the three-phase alternating current motor 105, as shown in fig. 22, then, the current in the inductor L flows through the external equipment connected with the charging interface, flows through the three-phase alternating current motor 105, flows through the second lower bridge arm 2, the fourth lower bridge arm VT4, the fourth lower bridge arm VT 52 and the fourth upper bridge VT7 and the external equipment connected with the inductance L, The sixth lower bridge arm VT6 flows into the eighth lower bridge diode VD8, and flows back to the inductor L through the eighth lower bridge diode VD8, so that the inductor L and the inductive energy in the three-phase ac motor 105 are released, and the step-down discharge is realized. As shown in fig. 23, when the charging interface is required to output a direct current with negative upper and positive lower, the current of the power battery 107 flows through the first upper bridge arm VT1, the third upper bridge arm VT3 and the fifth upper bridge arm VT5, the inductance of the three-phase ac motor 105, the external device and the inductance L connected to the charging interface are controlled to be simultaneously turned on, and then flow back to the battery through the eighth lower bridge arm VT8 to store energy for the inductance L and the three-phase ac motor 105, as shown in fig. 24, the current in the inductance of the three-phase ac motor 105 flows through the external device connected to the charging interface, flows through the inductance L, flows through the seventh upper bridge diode VT7, flows through the first upper bridge arm 1, the third upper bridge arm VT3 and the fifth upper bridge arm 5, flows through the first upper bridge arm 1, the third upper bridge arm 3 and the fifth upper bridge arm VT 4626, and flows back to the inductance v 5, the release of inductance energy in the inductance L and the three-phase alternating current motor 105 is realized, and the voltage reduction discharge is realized.

An eighth embodiment of the present application provides a heating method for a motor control circuit based on the first embodiment, where the eighth embodiment provides the heating method for heating a power battery by taking power from an external power module, and the heating method includes:

when a control instruction that the power battery needs to be heated is acquired and the three-phase alternating current motor is in a non-driving state, controlling the first switch module and the second switch module so that the power battery receives alternating current output by the external power supply module;

the first switch module, the power switch module and the three-phase inverter are controlled to enable the external power supply module to alternately perform a charging process of a three-phase coil of the three-phase alternating current motor and a discharging process of the three-phase coil of the three-phase alternating current motor, so that the three-phase inverter and the 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, and when the heated heat exchange medium flows through the power battery again, the temperature of the power battery is increased.

In the above steps, due to the inherent characteristics of the battery, the charge and discharge capacity of the power battery 107 is greatly reduced in the low temperature state, which may affect the use of the new energy vehicle in cold regions, and in order to make the power battery 107 work normally, the temperature of the power battery 107 needs to be raised when the temperature of the power battery 107 is too low, so that the temperature of the power battery 107 is obtained through the control module 108, the battery manager may be adopted to obtain the temperature of the power battery 107, the temperature of the power battery 107 is compared with the preset temperature value to determine whether the power battery 107 is in the 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 the heat exchange medium flowing through the power battery 107, when the external power supply module 101 is connected, the heat exchange medium flowing through the power battery 107 may be heated by the external power supply module 101, since both the three-phase inverter 104 and the three-phase ac motor 105 generate heat during operation, 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, the heat transfer medium may be heated by operating the three-phase inverter 104 and the three-phase ac motor 105, the first switching module 102, the second switching module 106, the power switching module 103, and the three-phase inverter 104 may be controlled to form a charging circuit with the first switching module 102, the second switching module 106, the power switching module 103, the three-phase inverter 104, the three-phase ac motor 105, and the external power module 101, the external power module 101 may charge the three-phase coils of the three-phase ac motor 105 through the charging circuit, and the external power module 101 may be turned off after the charging is completed, and the first switching module 102 may be turned on, The three-phase inverter 104 and the three-phase ac motor 105 form a discharge circuit, and the three-phase inverter 104 is discharged to heat the heat transfer medium flowing through the power battery 107 by the three-phase inverter 104 and the three-phase ac motor 105. This application embodiment draws forth the neutral conductor in three-phase alternating current motor 105, and then constitutes different return circuits with external power module 101, power switch module 103 and three-phase inverter 104, provide the heat source through the inside three-phase coil of three-phase alternating current motor 105, three-phase inverter 104 and inside device that generates heat thereof, realize the heating to power battery 107 through former cooling circuit behind the heating heat transfer medium, need not use the engine or increase heating device just can realize promoting power battery 107's temperature, and heating efficiency is high, power battery 107 temperature risees fast.

Further, the power switch module 103 includes a seventh power switch unit and an eighth power switch unit, the seventh power switch unit and the eighth power switch unit are connected in series and then connected in parallel with the three-phase inverter 104, and the positive electrode of the external power supply module 101 is connected to the seventh power switch unit and the eighth power switch unit through the first switch;

controlling the power switching module 103 and the three-phase inverter 104 to alternately perform a charging process of the three-phase coil of the three-phase ac motor 105 and a discharging process of the three-phase coil of the three-phase ac motor 105 by the external power supply module 101 includes:

when the external power supply module 101 outputs alternating current and is in the first half cycle, and current flows to the three-phase inverter 104 through the three-phase alternating current motor 105 at the moment, when it is acquired that the output voltage of the external power supply module 101 reaches a first preset value, the power switch in the seventh power switch unit or the power switch in the three-phase inverter 104 is controlled to be turned on, so that the external power supply module 101 charges the three-phase coil of the three-phase alternating current motor 105 first, and then the three-phase coil of the three-phase alternating current motor 105 discharges the external power supply module 101 until the output current of the three-phase coil of the three-phase alternating current motor 105 is 0, and the power switch is controlled to be turned off;

when the output ac of the external power supply module 101 is in the second half cycle, and at this time, when the current flows to the three-phase inverter 104 through the power switch module 103, and it is obtained that the output voltage of the external power supply module 101 reaches the first preset value, the power switch in the eighth power switch unit or the power switch in the three-phase inverter 104 is controlled to be turned on, so that the external power supply module 101 charges the three-phase coil of the three-phase ac motor 105 first, and then the three-phase coil of the three-phase ac motor 105 discharges the external power supply module 101, until the output current of the three-phase coil of the three-phase ac motor 105 is 0, the power switch is controlled to be turned off.

In another embodiment, the capacitor module is located between the three-phase inverter and the second switch module and is connected in parallel with the three-phase inverter;

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

when the external power supply module outputs alternating current and is in the first half period and the output voltage of the external power supply module reaches a first preset value, controlling a power switch in a seventh power switch unit to be switched on to switch on a power switch in a three-phase inverter so as to switch on a third heating loop, enabling the external power supply module to charge a three-phase coil of the three-phase alternating current motor, then enabling the three-phase coil of the three-phase alternating current motor to discharge the external power supply module, and controlling the power switch to be switched off until the output current of the three-phase coil of the three-phase alternating current motor is 0;

when the external power supply module outputs alternating current and is in a latter half period, and the output voltage of the external power supply module is obtained to reach a first preset value, the power switch in the eighth power switch unit and the power switch in the three-phase inverter are controlled to be conducted to enable the sixth heating loop to be conducted, so that the external power supply module firstly charges the three-phase coil of the three-phase alternating current motor, then the three-phase coil of the three-phase alternating current motor discharges the external power supply module, and the power switch is controlled to be turned off until the output current of the three-phase coil of the three-phase alternating current motor is 0.

The external power module 101 is powered and heated, and the implementation process is as follows, wherein the external power module 101 is powered and heated by a power battery circuit as shown in fig. 25 to 30:

the following process of heating power taken out from the external power module 101 by a specific circuit structure includes the following steps:

as shown in fig. 25, the first heating loop is: the power supply system comprises an external power supply module 101, a switch K1, a three-phase alternating-current motor 105, an upper bridge power switch (a first upper bridge diode VD1, a third upper bridge diode VD3 and a fifth upper bridge diode VD5) of a three-phase inverter 104, a seventh upper bridge arm VT7, an inductor L and a switch K2.

As shown in fig. 26, the second heating loop is: the external power supply module 101, the switch K1, the three-phase ac motor 105, the lower bridge power switch (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, the eighth lower bridge diode VD8, the inductor L, and the switch K2 form a first reverse energy storage loop.

As shown in fig. 27, the third heating loop is: a third heating circuit is formed by the external power supply module 101, the switch K1, the three-phase alternating-current motor 105, lower bridge power switches (a second lower bridge arm VT2, a fourth lower bridge arm VT4 and a sixth lower bridge arm VT6) of the three-phase inverter 104, the capacitor C, the seventh upper bridge arm VT7, the inductor L and the switch K2.

As shown in fig. 28, the fourth heating loop is: the external power supply module 101, the switch K2, the inductor L, the seventh lower bridge diode VD7, the upper bridge power switches (the first upper bridge arm VT1, the third upper bridge arm VT3, and the fifth upper bridge arm VT5) of the three-phase inverter 104, the three-phase ac motor 105, and the switch K1 form a fourth heating circuit.

As shown in fig. 29, the fifth heating circuit is: the external power supply module 101, the switch K2, the inductor L, the eighth lower bridge arm VT8, the upper bridge power switch (the second lower bridge diode VD2, the fourth lower bridge diode VD4, the sixth lower bridge diode VD6) of the three-phase inverter 104, the three-phase ac motor 105, and the switch K1 form a fifth heating loop.

As shown in fig. 30, the sixth heating loop is: the external power supply module 101, the switch K2, the inductor L, the eighth lower arm VT8, the capacitor C, the upper bridge power switches of the three-phase inverter 104 (the first upper arm VT1, the third upper arm VT3, and the fifth upper arm VT5), the three-phase ac motor 105, and the switch K1 form a third energy storage loop.

When the alternating current output by the external power supply module is in a period from-90 degrees to 90 degrees, the first heating circuit, the second heating circuit or the third heating circuit can be controlled to be conducted:

for the first heating circuit, as shown in fig. 25, when the ac output by the external power supply module is between-90 degrees and 0 degrees, the seventh upper arm VT7 is controlled to be turned on, so that the external power supply module stores energy in the inductor and the three-phase ac motor through the first heating circuit, when the ac input voltage is between 0 ° and 90 ° of the positive half cycle, the stored energy in the inductor of the motor is released to the grid, and when the current in the inductor of the motor is 0, the seventh upper arm VT7 is turned off.

For the second heating circuit, as shown in fig. 26, when the ac output by the external power supply module is between-90 degrees and 0 degrees, the second lower arm VT2, the fourth lower arm VT4, and the sixth lower arm VT6 are controlled to be turned on, so that the external power supply module stores energy in the inductor and the three-phase ac motor through the second heating circuit, when the ac input voltage is between 0 ° and 90 ° in the positive half-cycle, the motor inductor stores energy and is released to the power grid, and when the current in the motor inductor is 0, the second lower arm VT2, the fourth lower arm VT4, and the sixth lower arm VT6 are turned off.

For the third heating circuit, as shown in fig. 27, when the ac output by the external power supply module is between-90 degrees and 0 degrees, the seventh upper arm VT7, the second lower arm VT2, the fourth lower arm VT4, and the sixth lower arm VT6 are controlled to be turned on, so that the external power supply module stores energy in the inductor and the three-phase ac motor through the third heating circuit, when the ac input voltage is between 0 degrees and 90 degrees in a positive half cycle, the motor inductor stores energy and is released to the grid, and when the current in the motor inductor is 0, the seventh upper arm VT7, the second lower arm VT2, the fourth lower arm VT4, and the sixth lower arm VT6 are turned off.

When the alternating current output by the external power supply module is in a period of 90-270 degrees, the fourth heating circuit, the fifth heating circuit or the sixth heating circuit can be controlled to be conducted:

as for the fourth heating circuit, as shown in fig. 28, when the ac output by the external power supply module is between 90 degrees and 180 degrees, the first upper arm VT1, the third upper arm VT3, and the fifth upper arm VT5 are controlled to be turned on, so that the external power supply module stores energy in the inductor and the three-phase ac motor through the fourth heating circuit, when the ac input voltage is between 180 degrees and 270 degrees of the positive half cycle, the motor inductor stored energy is released to the power grid, and when the current in the motor inductor is 0, the first upper arm VT1, the third upper arm VT3, and the fifth upper arm VT5 are turned off.

For the fifth heating loop, as shown in fig. 29, when the ac output by the external power supply module is between 90 degrees and 180 degrees, the eighth lower arm VT8 is controlled to be turned on, so that the external power supply module stores energy in the inductor and the three-phase ac motor through the fifth heating loop, when the ac input voltage is between 180 degrees and 270 degrees of the positive half cycle, the stored energy in the inductor of the motor is released to the grid, and when the current in the inductor of the motor is 0, the eighth lower arm VT8 is turned off.

For the sixth heating circuit, as shown in fig. 30, when the alternating current output by the external power supply module is between 90 degrees and 180 degrees, the eighth lower bridge arm VT8, the first upper bridge arm VT1, the third upper bridge arm VT3, and the fifth upper bridge arm VT5 are controlled to be turned on, so that the external power supply module stores energy in the inductor and the three-phase alternating current motor through the sixth heating circuit, when the alternating current input voltage is between 180 degrees and 270 degrees of the positive half cycle, the stored energy in the motor inductor is released to the power grid, and when the current in the motor inductor is 0, the eighth lower bridge arm VT8, the first upper bridge arm VT1, the third upper bridge arm VT3, and the fifth upper bridge arm VT5 are turned off.

Different control strategies can be adopted according to actual requirements, and the following concrete steps are as follows:

wherein, by outputting PWM control signals to the power switch module 103 and the three-phase inverter 104, the power switch unit in the power switch module 103 and the power switch unit in the three-phase inverter 104 form different charging loops, so as to conduct different charging loops according to the alternating current output by the external power module 101, as shown in table 1, the seventh power switch unit in the power switch module 103 is represented by a symbol (i), the eighth power switch unit in the power switch module 103 is represented by a symbol (ii), the first upper bridge arm VT1, the third upper bridge arm VT3 and the fifth upper bridge arm VT5 in the upper bridge power switch in the three-phase inverter 104 are represented by a symbol (iii), the second lower bridge arm VT2, the fourth lower bridge arm VT4 and the sixth lower bridge arm VT6 in the lower bridge power switch in the three-phase inverter 104 are represented by a symbol (iv), the preset value UG is a positive value greater than 0, and IL is the current in the three-phase coil, the method comprises the following control strategies:

and (3) control strategy A: when the output alternating current of the external power supply module 101 flows to the three-phase inverter 104 through the three-phase alternating current motor 105, namely the phase of the alternating current is between-90 degrees and 0 degrees, the seventh power switch unit is controlled to be turned on when the output voltage of the external power supply module 101 reaches a first preset value-UG, the external power supply module 101 stores energy for the three-phase alternating current motor 105, when the alternating current input voltage is between 0 ° and 90 ° of a positive half cycle, the stored energy of the motor inductor is released to a power grid, and when the current in the motor inductor is 0, the seventh power switch unit is turned off. When the alternating current input voltage is within a certain voltage threshold UG between 90 degrees and 180 degrees in a positive half cycle, the first upper bridge arm VT1, the third upper bridge arm VT3 and the fifth upper bridge arm VT5 of the switching tube are controlled to be conducted to charge and store energy for the motor inductor, when the alternating current input voltage is within the positive half cycle between 180 degrees and 270 degrees, the first upper bridge arm VT1, the third upper bridge arm VT3 and the fifth upper bridge arm VT5 are turned off after current flow in the motor inductor is obtained, so that current circularly flows in the motor inductor to generate heat in one period of the grid voltage and a bus is not charged, the voltage of a bus capacitor is within a safety range, and the control simultaneously realizes zero current turn-on and turn-off of the first upper VT1, the third upper bridge arm VT3, the fifth upper bridge arm VT5 and the seventh power switching unit and only conducts loss to realize soft switching heating of the switching tube. The magnitude of the heating current is controlled by controlling the magnitude of UG amplitude, and then the heating power is controlled. The control policy B, C, D, E refers to the control policy a, which is not described herein again, and preferably adopts the control policy E, which can balance utilization of power devices, balance heating, and balance device lifetimes.

TABLE 1

In another embodiment, the voltage UG and the margin voltage δ U can be summarized as the following table 2 in combination with the control strategy, where UG and δ U are positive values greater than 0, and the margin voltage δ U is also used to ensure that the switching tube is turned off when the inductor current is 0.

TABLE 2

The heating method in the eighth embodiment may also be applied to the motor control circuit provided in the second to fifth embodiments, and the charging method includes:

when a control instruction that the power battery needs to be heated is acquired and the three-phase alternating current motor is in a non-driving state, the first switch module and the second switch module are controlled so that the power battery receives direct current or alternating current output by the external power supply module;

The ninth embodiment of the present application provides a heating method for a power battery, and based on the motor control circuit provided in the first embodiment, the heating method includes:

when the power battery needs to be heated, the first switch module is controlled to be conducted, the power switch module and the three-phase inverter are controlled to enable the power battery to alternately perform a charging process of a three-phase coil of the three-phase alternating current motor and a discharging process of the three-phase coil of the three-phase alternating current motor, and therefore the three-phase inverter and the three-phase alternating current motor can heat a heat exchange medium flowing through at least one of the three-phase inverter and the three-phase alternating current motor.

The present embodiment is different from the above-described embodiments in that when the external power supply module 101 is not connected, the heating of the heat exchange medium can be realized by discharging the power battery 107, the first switch module 102, the second switch module 106, the power switch module 103 and the three-phase inverter 104 are controlled to form a charging loop by controlling the first switch module 102, the second switch module 106, the power switch module 103, the three-phase inverter 104, the three-phase alternating current motor 105 and the power battery 107, the power battery 107 charges the three-phase alternating current motor 105 through the charging loop, the power battery 107 is turned off after the charging is finished, then the first switch module 102, the power switch module 103, the three-phase inverter 104 and the three-phase alternating current motor 105 form a discharging loop, and the three-phase alternating current motor 105 is discharged, so that the three-phase inverter 104 and the three-phase ac motor 105 heat the heat exchange medium flowing through the power battery 107.

The power switch module comprises a seventh power switch unit and an eighth power switch unit, a first heating energy storage loop is formed by the power battery, the second switch module, the three-phase inverter, the three-phase alternating current motor, the first switch module and the eighth power switch unit, the first follow current loop is formed by the three-phase alternating current motor, the three-phase inverter, the eighth power switch unit and the first switch module, and the second follow current loop is formed by the three-phase alternating current motor, the first switch module, the seventh power switch unit and the three-phase inverter;

the control power switch module and three-phase inverter make the charging process of three-phase coil and three-phase coil of three-phase alternating current motor of power battery to three-phase coil of three-phase alternating current motor go on alternately, include:

controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter to enable the first heating energy storage loop and the first follow current loop to be alternately conducted;

or the seventh power switch unit, the eighth power switch unit and the three-phase inverter are controlled to alternately conduct the first heating energy storage loop and the second freewheeling loop.

The power switch module comprises a seventh power switch unit and an eighth power switch unit, a second heating energy storage loop is formed by the power battery, the second switch module, the seventh power switch unit, the first switch module, the three-phase alternating current motor and the three-phase inverter, a third follow current loop is formed by the three-phase alternating current motor, the three-phase inverter, the eighth power switch unit and the first switch module, and a fourth follow current loop is formed by the three-phase alternating current motor, the first switch module, the seventh power switch unit and the three-phase inverter;

controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter to alternately conduct the second heating energy storage loop and the third freewheeling loop;

or the seventh power switch unit, the eighth power switch unit and the three-phase inverter are controlled to enable the second heating energy storage loop and the fourth freewheeling loop to be alternately conducted.

The power is taken from the power cell 107 to heat the cell. The implementation process is as follows, wherein the power battery 107 is provided with circuits for electricity and heat power batteries as shown in fig. 31 to fig. 36:

the following process of heating power from the power battery through a specific circuit structure, wherein the loop for storing energy to the energy storage unit and the three-phase alternating-current motor through the power battery comprises a first heating energy storage loop and a second heating energy storage loop, and as shown in fig. 31, the first heating energy storage loop is as follows: the current passes through a positive electrode of a 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 a three-phase inverter 104, a first heating energy storage loop formed by a three-phase coil of the motor, a switch K5, an inductor L, an eighth lower bridge arm VT8 and a switch K4, and the inductor L and the three-phase coil of the motor are charged by the power battery 107; as shown in fig. 32, the second heating energy storage loop is: the current passes through a positive electrode of the power battery 107, a switch K3, a seventh upper bridge arm VT7, an inductor L, a switch K5, a three-phase coil of the motor, a second heating energy storage loop formed by a lower bridge power switch (a second lower bridge arm VT2, a fourth lower bridge arm VT4 and a sixth lower bridge arm VT6) of the three-phase inverter 104 and the switch K4, and the inductor L and the three-phase coil of the motor are charged by the power battery 107.

After energy storage is completed, follow current is performed by controlling the power switch, follow current is performed through the inductor and the three-phase alternating-current motor, the follow current loop corresponding to the first heating energy storage loop comprises a first follow current loop and a second follow current loop, and as shown in fig. 33, the first follow current loop is: the current flowing out of the inductor L passes through an eighth lower bridge arm VT8, 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 freewheeling loop; as shown in fig. 34, the second freewheel circuit is: the current flowing out of the inductor L passes through a seventh upper bridge diode VD7, 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 heating energy storage circuit include a third freewheel circuit and a fourth freewheel circuit, as shown in fig. 35, 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) and an eighth lower bridge diode VD8 to form a third freewheeling circuit; as shown in fig. 36, 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 process of controlling the power battery to take power for heating by the control module 108 includes:

the battery manager controls the switch K3, the switch K4 and the switch K5 to be switched on, the switch K5 to be switched off, and the motor controller controls the seventh upper bridge arm VT7, the eighth lower bridge arm VT8 and the three-phase inverter to enable the first heating energy storage loop and the first follow current loop to be alternately switched on; or the first heating energy storage loop and the second follow current loop are controlled to be alternately conducted, or the motor controller controls the second heating energy storage loop and the third follow current loop to be alternately conducted; or the second heating energy storage loop and the fourth follow current loop are controlled to be alternately conducted, so that the power battery is powered to heat.

Another embodiment of the present application provides a vehicle, and the electric vehicle further includes the motor control circuit provided in the second to fifth embodiments.

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 depart from the spirit and scope of the embodiments of the present application, and they should be construed as being included in the present application.

Claims

1. A motor control circuit is characterized by comprising a first switch module, a power switch module, a three-phase inverter, a three-phase alternating current motor, a second switch module and a control module, the three-phase inverter is connected with the first end and the second end of the power switch module in parallel, the three-phase inverter is also connected with a power battery through the second switch module, a three-phase bridge arm of the three-phase inverter is connected with a three-phase coil of the three-phase alternating current motor, a third end of the power switch module and a connection point of the three-phase coil of the three-phase alternating current motor form a charging port, the charging port is connected with an external power supply module through the first switch module, and the control module is respectively connected with the first switch module, the power switch module, the three-phase inverter, the three-phase alternating current motor and the second switch module.

2. The motor control circuit of claim 1, wherein the motor control circuit comprises a first energy storage module, a third end of the power switch module is connected with a first end of the first energy storage module, and a second end of the first energy storage module and a connection point of a three-phase coil of the three-phase alternating current motor form a charging port;

or, the motor control circuit comprises a first energy storage module and a second energy storage module, the third end of the power switch module is connected with the first end of the first energy storage module, the connection point of the three-phase coil of the three-phase alternating current motor is connected with the first end of the second energy storage module, and the second end of the first energy storage module and the second end of the second energy storage module form a charging port.

3. The motor control circuit of claim 1 wherein a first terminal of said first switch module is connected to a third terminal of said power switch module in said charging port and a second terminal of said first switch module is connected to said external power module;

or the first end of the first switch module is connected to a connection point of a three-phase coil of the three-phase alternating current motor in the charging port, and the second end of the first switch module is connected to the external power supply module.

4. The motor control circuit according to claim 1, wherein a first terminal of the first switch module is connected to a third terminal of the power switch module in the charging port, a second terminal of the first switch module is connected to a connection point of a three-phase coil of the three-phase ac motor in the charging port, and the third terminal and the fourth terminal of the first switch module are respectively connected to positive and negative electrodes of the external power supply module.

5. The motor control circuit of claim 4 wherein said first switch module includes a first switch and a second switch, said motor control circuit being connected to an external power module through a first terminal of said first switch and a first terminal of said second switch, a second terminal of said second switch forming a first terminal of said first switch module, a second terminal of said first switch forming a second terminal of said first switch module.

6. The motor control circuit of claim 5 wherein the first switch module further comprises a fifth switch, two terminals of the fifth switch being connected to the second terminal of the second switch and the second terminal of the first switch, respectively.

7. The motor control circuit of claim 4 further comprising a rectifier switch, a positive terminal of the rectifier switch being connected to the second terminal of the three-phase inverter, and a first negative terminal and a second negative terminal of the rectifier switch being connected to the first terminal and the second terminal of the first switch module, respectively.

8. The motor control circuit of claim 4 wherein said first switch module comprises a first switch and a second switch; the power switch module comprises a seventh power switch unit and an eighth power switch unit which form a bridge arm and are connected in series; the three-phase inverter comprises a first power switch unit and a fourth power switch unit which form a three-phase bridge arm and are connected in series, a third power switch unit and a sixth power switch unit which are connected in series, and a fifth power switch and a second power switch which are connected in series; the second end of the first switch is connected between the seventh power switch unit and the eighth power switch unit.

9. The motor control circuit of claim 4 wherein said first switch module comprises a fifth switch, a first/second switch comprising a first switch and a second switch, said first switch, said fifth switch and said second switch being connected in series; the power switch module comprises a seventh power switch unit and an eighth power switch unit which form a bridge arm and are connected in series; the three-phase inverter comprises a first power switch unit and a fourth power switch unit which form a three-phase bridge arm and are connected in series, a third power switch unit and a sixth power switch unit which are connected in series, and a fifth power switch and a second power switch which are connected in series; the connection point of the first switch and the fifth switch is connected with the connection point of the seventh power switch unit and the eighth power switch unit, and the connection point of the fifth switch and the second switch is connected with the connection point of the three-phase coil of the three-phase alternating current motor.

10. The motor control circuit of claim 9 further comprising an energy storage module comprising at least one of a first energy storage device and a second energy storage device, wherein the first energy storage device is disposed between a connection point of the second switch and the fifth switch and a connection point of the seventh power switch cell and the eighth power switch cell; the second energy storage device is arranged between a connection point of the first switch and the fifth switch and a connection point of a three-phase coil of the three-phase alternating-current motor.

11. The motor control circuit of claim 9 further comprising a rectifier switch, wherein the rectifier switch comprises a first diode and a second diode, an anode of the first diode, an anode of the second diode, an output of the eighth power switch unit, an output of the fourth power switch unit, an output of the sixth power switch unit and an output of the second power switch unit are connected, a cathode of the first diode is connected to a connection point of the second switch and the fifth switch, and a cathode of the second diode is connected to a connection point of the first switch and the fifth switch.

12. A charging method for a power battery, based on the motor control circuit of any one of claims 1 to 11, characterized in that the charging method comprises:

13. The charging method according to claim 12, wherein the charging mode is a boost charging mode, and the output type of the external power supply module is direct current;

controlling the first switch module, the second switch module, the power switch module, and the three-phase inverter to charge the power battery, including:

controlling the first switch module, the second switch module, the power switch module and the three-phase inverter to alternately perform a charging process of the external power supply module on a three-phase coil of the three-phase alternating current motor and a discharging process of the external power supply module and the three-phase coil of the three-phase alternating current motor on the power battery, so as to boost a charging voltage of the external power supply module and then charge the power battery;

the charging mode is a boosting charging mode, and the output type of the external power supply module is alternating current;

and controlling the first switch module, the second switch module, the power switch module and the three-phase inverter to alternately perform a charging process of the external power supply module on a three-phase coil of the three-phase alternating current motor and a discharging process of the external power supply module and the three-phase coil of the three-phase alternating current motor on the power battery so as to boost the charging voltage of the external power supply module and then charge the power battery.

14. The charging method according to claim 13, wherein the power switch module includes a seventh power switch unit and an eighth power switch unit, the external power supply module, the first switch module, the eighth power switch unit, the three-phase inverter, and the three-phase ac motor constitute a first tank circuit, and the external power supply module, the first switch module, the seventh power switch unit, the second switch module, the power battery, the three-phase inverter, and the three-phase ac motor constitute a first charging circuit;

the alternating performing of the energy storage process of the external power supply module to the three-phase coil of the three-phase alternating current motor and the charging process of the external power supply module and the three-phase coil of the three-phase alternating current motor to the power battery includes:

and controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter to enable the first energy storage loop and the first charging loop to be conducted alternately.

15. The charging method according to claim 13, wherein the power switch module includes a seventh power switch unit and an eighth power switch unit, the external power supply module, the first switch module, the seventh power switch unit, the three-phase inverter, and the three-phase ac motor constitute a second tank circuit, and the external power supply module, the first switch module, the seventh power switch unit, the second switch module, the power battery, the three-phase inverter, and the three-phase ac motor constitute a first charging circuit;

16. The charging method of claim 13, wherein the motor control circuit further comprises a capacitance module located between the three-phase inverter and the second switching module and connected in parallel with the three-phase inverter;

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

the alternating the charging process of the three-phase coil of the three-phase alternating current motor and the capacitor module by the external power supply module and the discharging process of the power battery by the three-phase coil of the three-phase alternating current motor by the external power supply module includes:

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

17. The charging method of claim 13, wherein the motor control circuit further comprises a capacitance module located between the three-phase inverter and the second switching module and connected in parallel with the three-phase inverter;

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

and controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter to alternately conduct the third reverse energy storage loop and the first reverse charging loop.

18. A discharging method of a power battery, based on the motor control circuit of claim 1, characterized in that the discharging method comprises:

19. The discharging method according to claim 18, wherein the selecting the discharging mode according to the voltage of the electricity utilization module and the voltage of the power battery comprises:

when the obtained voltage of the power battery is higher than the voltage of the electricity utilization module, a voltage reduction discharge mode is selected;

controlling the power switch module and the three-phase inverter to enable the power battery to discharge the power utilization module according to the selected discharge mode, wherein the method comprises the following steps:

and controlling the power switch module and the three-phase inverter to alternately perform a charging process of the three-phase coil of the three-phase alternating current motor by the power battery and a discharging process of the three-phase coil of the three-phase alternating current motor to the electricity utilization module, so as to discharge the electricity utilization module after reducing the charging voltage of the power battery.

20. The discharge method according to claim 19, wherein the power switch modules include a seventh power switch unit and an eighth power switch unit, the power battery, the second switch module, the seventh power switch unit, the first switch module, the power-using module, the three-phase ac motor, and the three-phase inverter constitute a first discharge energy storage circuit, and the three-phase ac motor, the three-phase inverter, the eighth power switch unit, the first switch module, and the power-using module constitute a first discharge circuit;

the alternating performing of the charging process of the three-phase coil of the three-phase alternating current motor by the power battery and the discharging process of the three-phase coil of the three-phase alternating current motor to the power utilization module includes:

and controlling the seventh power switch unit, the eighth power switch unit and the three-phase inverter to enable the first discharging energy storage loop and the first discharging loop to be alternately conducted.

21. The discharge method according to claim 19, wherein the power switch modules include a seventh power switch unit and an eighth power switch unit, the power battery, the second switch module, the three-phase inverter, the three-phase ac motor, the electricity utilization module, the first switch module, and the eighth power switch unit form a second discharge energy storage loop, and the three-phase ac motor, the three-phase inverter, the seventh power switch unit, the first switch module, and the electricity utilization module form a second discharge loop;

and controlling a seventh power switch unit, an eighth power switch unit and the three-phase inverter to enable the second discharging energy storage loop and the second discharging loop to be alternately conducted.

22. A method for heating a power battery, based on the motor control circuit of any one of claims 1 to 11, the method comprising:

the first switching module, the power switching module, and the three-phase inverter are controlled such that a charging process of a three-phase coil of the three-phase ac motor and a discharging process of the three-phase coil of the three-phase ac motor by the external power supply module are alternately performed, so that the three-phase inverter and the three-phase ac motor heat a heat exchange medium flowing through at least one of the three-phase inverter and the three-phase ac motor.

23. The heating method according to claim 22, wherein the power switching module includes a seventh power switching unit and an eighth power switching unit, the seventh power switching unit and the eighth power switching unit are connected in series and then connected in parallel to the three-phase inverter, one end of the external power supply module is connected to the seventh power switching unit and the eighth power switching unit through a first switch, and the other end of the external power supply module is connected to a connection point connected to a three-phase coil of the three-phase ac motor through the first switch;

the controlling the power switching module and the three-phase inverter to alternately perform a charging process of the three-phase coil of the three-phase ac motor and a discharging process of the three-phase coil of the three-phase ac motor by the external power supply module includes:

when the external power supply module outputs alternating current and is in the first half period and the output voltage of the external power supply module reaches a first preset value, controlling a power switch in the seventh power switch unit or a power switch in the three-phase inverter to be switched on, so that the external power supply module firstly charges a three-phase coil of the three-phase alternating current motor, and then the three-phase coil of the three-phase alternating current motor discharges the external power supply module until the output current of the three-phase coil of the three-phase alternating current motor is 0, and controlling the power switch to be switched off;

when the external power supply module outputs alternating current and is in a latter half period, and the obtained output voltage of the external power supply module reaches a first preset value, controlling the power switch in the eighth power switch unit or the power switch in the three-phase inverter to be switched on, so that the external power supply module firstly charges a three-phase coil of the three-phase alternating current motor, and then the three-phase coil of the three-phase alternating current motor discharges the external power supply module until the output current of the three-phase coil of the three-phase alternating current motor is 0, and controlling the power switch to be switched off.

24. The heating method according to claim 22, wherein the power switching module includes a seventh power switching unit and an eighth power switching unit, the seventh power switching unit and the eighth power switching unit are connected in series and then connected in parallel to the three-phase inverter, one end of the external power supply module is connected to the seventh power switching unit and the eighth power switching unit through a first switch, the other end of the external power supply module is connected to a connection point connected to a three-phase coil of the three-phase ac motor through the first switch, and the motor control circuit further includes a capacitance module that is located between the three-phase inverter and the second switching module and is connected in parallel to the three-phase inverter;

the external power supply module, the first switch module, the seventh power switch unit, the three-phase inverter, the three-phase ac motor, and the capacitor module form a third heating circuit, and the external power supply module, the first switch module, the eighth power switch unit, the three-phase inverter, the three-phase ac motor, and the capacitor module form a sixth heating circuit;

when the external power supply module outputs alternating current and is in the first half period, and when the output voltage of the external power supply module is obtained to reach a first preset value, controlling a power switch in the seventh power switch unit and a power switch in the three-phase inverter to be conducted so as to conduct the third heating loop, enabling the external power supply module to charge a three-phase coil of the three-phase alternating current motor, and then enabling the three-phase coil of the three-phase alternating current motor to discharge the external power supply module until the output current of the three-phase coil of the three-phase alternating current motor is 0, and controlling the power switch to be turned off;

when the external power supply module outputs alternating current and is in a latter half period, and the output voltage of the external power supply module reaches a first preset value, controlling the power switch in the eighth power switch unit and the power switch in the three-phase inverter to be switched on to enable the sixth heating loop to be switched on, enabling the external power supply module to charge a three-phase coil of the three-phase alternating current motor firstly, then enabling the three-phase coil of the three-phase alternating current motor to discharge the external power supply module, and controlling the power switch to be switched off until the output current of the three-phase coil of the three-phase alternating current motor is 0.

25. A method for heating a power battery, based on the motor control circuit of any one of claims 1 to 11, the method comprising:

when the power battery needs to be heated, the first switch module is controlled to be conducted, the power switch module and the three-phase inverter are controlled to enable the power battery to alternately perform a charging process on a three-phase coil of the three-phase alternating current motor and a discharging process on the three-phase coil of the three-phase alternating current motor, and therefore the three-phase inverter and the three-phase alternating current motor can heat a heat exchange medium flowing through at least one of the three-phase inverter and the three-phase alternating current motor.

26. The heating method according to claim 25, wherein the power switch modules include a seventh power switch unit and an eighth power switch unit, the power battery, the second switch module, the three-phase inverter, the three-phase ac motor, the first switch module, and the eighth power switch unit form a first heated tank circuit, the three-phase ac motor, the three-phase inverter, the eighth power switch unit, and the first switch module form a first flywheel circuit, and the three-phase ac motor, the first switch module, the seventh power switch unit, and the three-phase inverter form a second flywheel circuit;

the controlling the power switch module and the three-phase inverter to alternately perform a charging process of the three-phase coil of the three-phase alternating current motor and a discharging process of the three-phase coil of the three-phase alternating current motor by the power battery includes:

controlling a seventh power switch unit, an eighth power switch unit and the three-phase inverter to enable the first heating energy storage loop and the first follow current loop to be alternately conducted;

or, the seventh power switch unit, the eighth power switch unit and the three-phase inverter are controlled to alternately conduct the first heating energy storage loop and the second freewheeling loop.

27. The heating method according to claim 25, wherein the power switch modules include a seventh power switch unit and an eighth power switch unit, the power battery, the second switch module, the seventh power switch unit, the first switch module, the three-phase ac motor, and the three-phase inverter constitute a second heating tank circuit, the three-phase ac motor, the three-phase inverter, the eighth power switch unit, and the first switch module constitute a third freewheel circuit, and the three-phase ac motor, the first switch module, the seventh power switch unit, and the three-phase inverter constitute a fourth freewheel circuit;

controlling a seventh power switch unit, an eighth power switch unit and the three-phase inverter to enable the second heating energy storage loop and the third freewheeling loop to be alternately conducted;

or, the seventh power switch unit, the eighth power switch unit and the three-phase inverter are controlled to alternately conduct the second heating energy storage loop and the fourth freewheeling loop.

28. A vehicle characterized by further comprising the motor control circuit of any one of claims 1 to 11.