Voltage Control of Electric Vehicle Permanent Magnet Synchronous Motor for Maximizing Energy Recovery Rate

In this paper, in order to maximize the energy recovery from an electric vehicle (EV) motor, we propose a new method to control the voltage generated by the permanent magnet synchronous motor (PMSM) of an EV. The method includes an L-C resonance circuit, and it controls the voltage to make the battery chargeable. Thus, it is possible to increase the energy recovery, which can increase the travel distance of the EV. The DC link voltage depends on the driving pulse of the control device. We analyzed the voltage of the resonance circuit, and to control this voltage, we proposed an algorithm using the PI duty controller. To verify this control algorithm, a simple simulator was constructed and simulated with a constant speed and the R-C circuit model. To make the simulations more realistic, we applied the load torque, which virtualizes the uphill and downhill driving of the vehicle. Simulation using the battery model was also conducted. The energy recovery rate was calculated, and the voltage control algorithm was verified.