Modelling and Simulation of a Two Speed Electric Vehicle

Electric vehicles offer an alternative to hybrid and conventional vehicles through the use of electric drive without fossil fuel consumption. This shifts green house gas production from the vehicle to power stations, but if power is supplied from renewable sources, such as wind power, zero emissions are generated. Practical vehicle design requires the consideration of competing demands of vehicle acceleration and performance against range and vehicle efficiency. Thus, considering requirements such as grade climbing and acceleration against vehicle range and power consumption, a two speed transmission is suggested for this vehicle study to increase motor operation at high torque and efficiency regions. To evaluate the application of such a transmission, a two speed electric vehicle powertrain is developed in Simulink® for a full sized sedan. Simulations are conducted to demonstrate the performance of the two speed electric vehicle. Results demonstrate the capability of the two speed vehicle to meet various performance criteria and provide an indication of effective range under different drive cycles.