Patent ID: 11876197
Assignee: BYD COMPANY LIMITED
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  B  Y | IPC B  H

Claim 11:
12. A power battery heating apparatus, for heating a power battery of a vehicle, the power battery heating apparatus comprising:
a three-phase inverter, connected to a positive electrode and a negative electrode of a heating energy source configured to provide heating energy;
a three-phase alternating current motor, wherein three phase coils of the three-phase alternating current motor are connected to three phase legs of the three-phase inverter; and
a controller, wherein the controller is respectively connected to the three-phase inverter and the three-phase alternating current motor, and is programmed to obtain a current temperature value of the power battery, and determine that the current temperature value of the power battery is lower than a preset temperature value, and obtain heating power of the power battery; the controller is further programmed to obtain a preset quadrature-axis current, and obtain a corresponding preset direct-axis current according to the heating power of the power battery, wherein a value of the obtained preset quadrature-axis current is a quadrature-axis current value that causes a torque value outputted by the three-phase alternating current motor to fall within a target range, and zero is not comprised in the target range; and
the controller is further programmed to control an on/off status of a power device in the three-phase inverter, so that the three-phase alternating current motor generates heat according to the heating energy provided by the heating energy source, to heat a coolant flowing through the power battery, and control, according to the preset direct-axis current and the preset quadrature-axis current, the three-phase inverter to adjust a phase current of the three-phase alternating current motor in the heating process, wherein a direction of the preset direct-axis current changes periodically in the heating process.