Simulation of a Traction System in an Electric Vehicle

In this paper the simulation of a mechanical coupled of two permanent magnet synchronous machines is realized, one of them acts as a traction machine in an electric vehicle (EV) and the other one generates the opposite torque according to the vehicle electric dynamic model. Although the regenerative braking system is a trend in electric traction systems, a dynamic braking system is simulated because this paper does not contemplate the bidirectional DC/DC converter for regenerative braking. Additionally, the dynamic model of the permanent magnet machine is obtained, which is used for field-oriented control. Space Vector Pulse Width Modulation (SVPWM) is used in the inverters of the traction machine and the synchronous machine, which is used in the electric vehicle emulator. Finally, the simulation is done with the SAEJ227 driving cycle that contains a constant acceleration period, a constant speed period and a braking period allowing obtain the vehicle behavior on these stages, showing the results as the speed response, the opposite torque developed by the electric vehicle emulator and the action of the dynamic brake.