An improved DTC strategy associated to a new averaged inverter model for electric vehicle application

Direct torque control (DTC) strategy is the most recent control technique for system drives. This method consists of the control of torque and the stator flux directly, based on their instantaneous errors. It allows a precise and a quick control of the induction machine flux and torque. This strategy is more and more used in electric vehicle application. The major drawback of this technique is that the switching frequency varies with mechanical speed, and it is not constant even in steady state condition. In this paper, we have proposed an improved DTC technique allowing the control of the semiconductors switching frequency. A new nonideal PWM switch model, which takes into account the semiconductor nonlinearities, is used in order to perform electrothermal simulations.