CN-116208048-B - Motor heating method and device, motor controller, electric automobile and storage medium

CN116208048BCN 116208048 BCN116208048 BCN 116208048BCN-116208048-B

Abstract

The invention discloses a motor heating method and device, a motor controller, an electric automobile and a storage medium, and relates to the technical field of electric automobiles; and controlling the motor to work in a step-out running mode according to the target high-frequency rotating current vector so as to generate motor loss, wherein the motor loss comprises copper loss and iron loss. The invention solves the problems of unbalanced heating of the three-phase winding and influence on the motor performance of the motor in the prior art, and realizes the effect of improving the heating efficiency of the power battery by the motor heating in the electric automobile.

Inventors

LIU LIBO
YAN LEYANG
JIN XIAOLONG

Assignees

苏州汇川联合动力系统有限公司

Dates

Publication Date: 20260505
Application Date: 20230303

Claims (11)

1. A method of heating an electric motor, the method comprising: Acquiring a motor heating instruction; obtaining a target high-frequency rotating current vector according to the motor heating instruction and a pre-stored corresponding relation, wherein the target high-frequency rotating current vector comprises a target current amplitude and a target rotating frequency; Controlling a motor to work in a step-out operation mode according to the target high-frequency rotating current vector so as to generate motor loss, and heating a power battery by utilizing heat generated by the motor loss, wherein the motor loss comprises copper loss and iron loss; the step-out operation mode of the motor is controlled according to the target high-frequency rotating current vector, and the step-out operation mode comprises the following steps: Controlling the motor to operate in a rotational frequency increasing mode in which a current amplitude of a high-frequency rotational current vector for controlling the motor to operate is kept zero, and a rotational frequency of the high-frequency rotational current vector for controlling the motor to operate is gradually increased to the target rotational frequency; controlling the motor to operate in a current amplitude increasing mode, wherein in the current amplitude increasing mode, the rotation frequency of a high-frequency rotation current vector for controlling the motor to operate is kept to be the target rotation frequency, and the current amplitude of the high-frequency rotation current vector for controlling the motor to operate gradually increases to the target current amplitude; and controlling the motor to run by using the high-frequency rotating current vector with the current amplitude as the target current amplitude and the rotating frequency as the target rotating frequency.
2. The method for generating heat by a motor according to claim 1, wherein said obtaining a target frequency rotation current vector according to the motor heating instruction and a pre-stored correspondence relation comprises: And obtaining the target high-frequency rotating current vector by utilizing the corresponding relation between the pre-stored motor heating power and the high-frequency rotating current vector according to the motor heating power extracted from the motor heating instruction.
3. The motor heating method according to claim 2, wherein the obtaining the target high-frequency rotating current vector according to the motor heating power extracted from the motor heating instruction by using a pre-stored correspondence between motor heating power and high-frequency rotating current vector comprises: and obtaining the target current amplitude and the target rotating frequency by utilizing the pre-stored corresponding relation among the motor heating power, the current amplitude and the rotating frequency according to the motor heating power extracted from the motor heating instruction and the NVH characteristic of the motor.
4. The motor heating method of claim 1, wherein after said controlling the motor to operate in the step-out operation mode based on said target high frequency rotational current vector to generate motor losses, said method further comprises: acquiring a motor heating stop instruction; and controlling the motor to exit the step-out running mode according to the motor heating stop instruction.
5. The method of heating an electric machine of claim 1, further comprising: Acquiring the temperature of the motor in the process that the motor works in a step-out running mode; when the temperature of the motor reaches an over-temperature protection threshold value, reducing the target current amplitude of the target high-frequency rotating current vector, and controlling the motor to work in a step-out running mode according to the adjusted target high-frequency rotating current vector.
6. The method of heating a motor of claim 4, wherein said controlling the motor to exit the out-of-step mode of operation comprises: controlling the motor to operate in a current amplitude reduction mode, in which the current amplitude of a high-frequency rotating current vector for controlling the motor to operate is gradually reduced to zero, and the rotating frequency of the high-frequency rotating current vector for controlling the motor to operate is maintained to be the target rotating frequency; And controlling the motor to operate in a rotation frequency reducing mode in which the rotation frequency of the high-frequency rotation current vector for controlling the motor to operate is gradually reduced to zero, and the current amplitude of the high-frequency rotation current vector for controlling the motor to operate is kept to zero.
7. A motor heating method as set forth in claim 1 or 6, wherein said controlling said motor operation includes: After determining the current amplitude and the rotation frequency of a high-frequency rotation current vector for controlling the operation of the motor, obtaining a command current; PI regulation is carried out according to the instruction current and the feedback current of the motor, so as to obtain a voltage signal; Performing space vector pulse width modulation on the voltage signal to obtain a pulse width modulation signal; and controlling an inverter to drive the motor to work according to the current amplitude and the rotating frequency according to the pulse width modulation signal.
8. A motor heating apparatus, the apparatus comprising: the instruction acquisition module is used for acquiring a motor heating instruction; The data acquisition module is used for acquiring a target high-frequency rotating current vector according to the motor heating instruction and a pre-stored corresponding relation, wherein the target high-frequency rotating current vector comprises a target current amplitude value and a target rotating frequency; the motor control module is used for controlling the motor to work in a step-out operation mode according to the target high-frequency rotating current vector so as to generate motor loss, and heating the power battery by utilizing heat generated by the motor loss, wherein the motor loss comprises copper loss and iron loss; The motor control module comprises a mode switching unit, wherein the mode switching unit is used for controlling the motor to operate in a rotating frequency increasing mode, the current amplitude of a high-frequency rotating current vector used for controlling the motor to operate is kept to be zero in the rotating frequency increasing mode, the rotating frequency of the high-frequency rotating current vector used for controlling the motor to operate gradually increases to the target rotating frequency, the motor is controlled to operate in the current amplitude increasing mode, the rotating frequency of the high-frequency rotating current vector used for controlling the motor to operate is kept to be the target rotating frequency in the current amplitude increasing mode, the current amplitude of the high-frequency rotating current vector used for controlling the motor to operate gradually increases to the target current amplitude, and the high-frequency rotating current vector used for controlling the motor to operate with the current amplitude as the target current amplitude and the rotating frequency as the target rotating frequency.
9. A motor controller, characterized in that it comprises a processor and a memory, on which a motor heating program is stored, which when executed by the processor, implements the motor heating method according to any one of claims 1 to 7.
10. An electric automobile, characterized by comprising: a power battery; A thermal management system; A motor; the motor controller of claim 9, coupled to the motor for controlling the motor to operate in a step-out mode of operation to produce motor losses, the motor losses including copper losses and iron losses; the thermal management system is used for transferring heat generated by the motor to the power battery so as to heat the power battery.
11. A computer-readable storage medium, on which a computer program is stored which, when executed by one or more processors, implements the motor heating method of any one of claims 1 to 7.

Description

Motor heating method and device, motor controller, electric automobile and storage medium Technical Field The invention relates to the technical field of electric automobiles, in particular to a motor heating method and device, a motor controller, an electric automobile and a storage medium. Background In the field of electric automobiles, under a low-temperature environment, a power battery is firstly subjected to heating treatment, and then the vehicle is started. At present, a common way to heat the power battery in an electric vehicle in a low temperature environment is to discharge the battery to the motor winding. In the process, besides the internal resistance of the battery, the motor can generate heat during operation, and then the heat generated by the motor is transferred to the battery through the thermal management system to realize heating. However, in this method, the current of each phase winding of the motor is different, so that the problem of unbalanced heating of the three-phase winding is caused, the heating capacity of the three-phase winding cannot be fully utilized, and the one-phase winding with more heating is aged faster, so that the motor performance is easily affected. Disclosure of Invention The invention mainly aims to provide a motor heating method and device, a motor controller, an electric automobile and a storage medium, and aims to solve the problem that in the prior art, motor heating has unbalanced heating of three-phase windings and motor performance is affected. In order to achieve the above purpose, the invention adopts the following technical scheme: in a first aspect, the present invention provides a method of heating an electric motor, the method comprising: Acquiring a motor heating instruction; Obtaining a target high-frequency rotating current vector according to a motor heating instruction, wherein the target high-frequency rotating current vector comprises a target current amplitude and a target rotating frequency; and controlling the motor to work in a step-out operation mode according to the target frequency rotating current vector so as to generate motor loss, wherein the motor loss comprises copper loss and iron loss. Optionally, in the motor heating method, after controlling the motor to operate in the out-of-step operation mode according to the target frequency rotating current vector to generate motor loss, the method further includes: acquiring a motor heating stop instruction; And controlling the motor to exit the step-out operation mode according to the motor heating stop instruction. Optionally, in the motor heating method, the method further includes: acquiring the temperature of the motor in the process that the motor works in a step-out operation mode; when the temperature of the motor reaches an over-temperature protection threshold, reducing the target current amplitude of the target frequency rotating current vector, and controlling the motor to work in a step-out operation mode according to the adjusted target frequency rotating current vector. Optionally, in the above motor heating method, controlling the motor to operate in a step-out operation mode according to the target frequency rotating current vector includes: Controlling the motor to operate in a rotational frequency increasing mode in which a current amplitude of a high-frequency rotational current vector for controlling the motor to operate is maintained to be zero, and the rotational frequency is gradually increased to a target rotational frequency; Controlling the motor to operate in a current amplitude increasing mode, wherein in the current amplitude increasing mode, the rotating frequency of a high-frequency rotating current vector for controlling the motor to operate is kept to be a target rotating frequency, and the current amplitude is gradually increased to be a target current amplitude; and controlling the motor to run by using the high-frequency rotating current vector with the current amplitude as a target current amplitude and the rotating frequency as a target rotating frequency. Optionally, in the above motor heating method, controlling the motor to exit from the step-out operation mode includes: Controlling the motor to operate in a current amplitude reduction mode, wherein in the current amplitude reduction mode, the current amplitude of a high-frequency rotating current vector for controlling the motor to operate is gradually reduced to zero, and the rotating frequency is kept to be the target rotating frequency; The motor operation is controlled in a reduced rotation frequency mode in which the rotation frequency of the high frequency rotating current vector used to control the motor operation is gradually reduced to zero and the current amplitude is maintained at zero. In a second aspect, the present invention provides a motor heating apparatus comprising: the instruction acquisition module is used for acquiring a motor heating instruction; The data acquisition