Abstract: An electric vehicle drive system, a backup power supply device and a backup power supply method for an electric vehicle drive system are provided. The method includes: converting a voltage on a high voltage DC bus of an electric vehicle into a backup input voltage; determining whether a low voltage battery in the electric vehicle drive system has power supply abnormity; and determining the backup input voltage to be an input voltage of a low voltage power supply circuit in the electric vehicle drive system, in a case that the low voltage battery has power supply abnormity.

Abstract: An electric vehicle drive system, a backup power supply device and a backup power supply method for an electric vehicle drive system are provided. The method includes: converting a voltage on a high voltage DC bus of an electric vehicle into a backup input voltage; determining whether a low voltage battery in the electric vehicle drive system has power supply abnormity; and determining the backup input voltage to be an input voltage of a low voltage power supply circuit in the electric vehicle drive system, in a case that the low voltage battery has power supply abnormity.

Abstract: A method and a system for acquiring a rotor position of a rotary transformer are provided. The system includes: a rotary transformer decoder, a low pass filter and a microprocessor, which includes a synchronous demodulation module and a calculation module. The rotary transformer decoder outputs an excitation signal and acquires first position information of the motor rotor. The calculation module performs calculation to acquire second position information of the motor rotor. The rotary transformer decoder and software decoding are integrated to acquire two rotor positions, and the two rotor positions are compared. In a case that a preset determining condition is met, one of the rotor positions is used for motor control, and the other is used as redundant data for backup, thereby improving the reliability of the acquired rotor position.

Abstract: A motor controller according to the present disclosure obtains the rotational speed determination signal of the motor through the microprocessor and the rotational speed collector, and then outputs the first control signal by the first logic operation circuit based on the speed of the motor, to make the driving circuit control the main circuit to work normally or enter the safety state. In addition, the motor controller generates and outputs the second shutoff signal by the monitoring chip based on the working state or the output instruction of the microprocessor, and then outputs the second control signal by the second logic operation circuit based on the second shutoff signal and whether the DC bus voltage of the main circuit is in an overvoltage state, to make the driving circuit control the main circuit to stop receiving the first control signal and enter the safety state.

Abstract: A motor controller according to the present disclosure obtains the rotational speed determination signal of the motor through the microprocessor and the rotational speed collector, and then outputs the first control signal by the first logic operation circuit based on the speed of the motor, to make the driving circuit control the main circuit to work normally or enter the safety state. In addition, the motor controller generates and outputs the second shutoff signal by the monitoring chip based on the working state or the output instruction of the microprocessor, and then outputs the second control signal by the second logic operation circuit based on the second shutoff signal and whether the DC bus voltage of the main circuit is in an overvoltage state, to make the driving circuit control the main circuit to stop receiving the first control signal and enter the safety state.

Abstract: A method and a system for acquiring a rotor position of a rotary transformer are provided. The system includes: a rotary transformer decoder, a low pass filter and a microprocessor, which includes a synchronous demodulation module and a calculation module. The rotary transformer decoder outputs an excitation signal and acquires first position information of the motor rotor. The calculation module performs calculation to acquire second position information of the motor rotor. The rotary transformer decoder and software decoding are integrated to acquire two rotor positions, and the two rotor positions are compared. In a case that a preset determining condition is met, one of the rotor positions is used for motor control, and the other is used as redundant data for backup, thereby improving the reliability of the acquired rotor position.