LAUSR

The series electro-hydraulic hybrid powertrain can improve the power characteristics of battery rail vehicles (BRVs) while also extending battery life and increasing vehicle mileage. A novel electric motor start-up method using the hydraulic pump/motor to reversely drive the permanent magnet synchronous motor (PMSM) to restart at a speed is proposed based on the energy reverse transfer characteristics between the electric motor and hydraulic pump/motor. PID controls the reverse driving process of the hydraulic motor. The zero vector voltage (ZVV) method is used to determine the initial speed and rotor position of the motor restart at a speed. The electric motor speed control adopts the speed sensorless space vector pulse width modulation (SVPWM) control based on the back-electromotive force (EMF) integration method. The simulation models are carried out in MATLAB/Simulink and AMESim and built a special test platform. The results show that the method for controlling electric motor restart is feasible and effective. The start-up current of the electric motor is related to its initial speed. The closer the initial speed is to its target speed, the smaller its start-up current is, the faster the electric motor reaches the stable target speed.