Large Driving Range Increase of Series Chopper Based Power Train Using Motor Test Bench

Authors proposed the series chopper based power train aimed for the extension of the driving range. In previous paper [1], under the condition of the constant DC-supply voltage, effectiveness of the optimization of the profile of the chopper output voltage was shown. However, the output voltage of the battery used in the actual EV varies depending on the state of charge (SOC). Because of this difference, the precise comparison of the power train was not performed. In this paper, by emulating the battery including the internal resistance and output voltage dependency on SOC, the driving range is compared in the motor test bench. It is shown that the chopper output voltage adjustment depending on the rotor speed and the weight of the chopper has large effect on the driving range. In comparison to non-chopper power train, the driving range of the series chopper power train increases by 2.1%. In addition, by decreasing the weight of the chopper by a half and zero, the driving range further extends by 1.4% and 3.0%.