This paper presents a new hybrid cascaded H-bridge multilevel inverter motor drive DTC scheme for electric vehicles where each phase of the inverter can be implemented using a single DC source. Traditionally, each phase of the inverter requires DC source for output voltage levels. In this paper, a scheme is proposed that allows the use of a single DC source as the first DC source which would be available from batteries or fuel cells, with the remaining ( ) DC sources being capacitors. This scheme can simultaneously maintain the capacitors of DC voltage level and produce a nearly sinusoidal output voltage due to its high number of output levels. In this context, high performances and efficient torque and flux control are obtained, enabling a DTC solution for hybrid multilevel inverter powered induction motor drives intended for electric vehicle propulsion. Simulations and experiments show that the proposed multilevel inverter and control scheme are effective and very attractive for embedded systems such as automotive applications. 1. Introduction Currently, automotive applications such as EV’s seem to constitute an increasingly effective alternative to conventional vehicles, allowing vehicle manufacturers to fulfill users requirements (dynamic performances and fuel consumption) and environmental constraints (pollutant emissions reduction) [1]. The electric propulsion system is the heart of EV. It consists of the motor drive, transmission device, and wheels. In fact, the motor drive, comprising the electric motor, the power converter, and the electronic controller, is the core of the EV propulsion system. The motor drive is configured to respond to a torque demand set by the driver [2]. The induction motor seems to be a very interesting solution for EV’s propulsion. FOC and DTC have emerged as the standard industrial solutions to achieve high dynamic performance [3–5]. However some drawbacks of both methods have motivated important research efforts in the last decades. Particularly for DTC, the high torque ripple and the variable switching frequency introduced by the hysteresis comparators have been extensively addressed [6, 7]. In addition, several contributions that combine DTC principles together with PWM and SVM have been reported to correct these problems. This approach is based on the load angle control, from which a voltage reference vector is computed which is finally modulated by the inverter [8]. Although one major feature of classic DTC is the absence of modulators and linear controllers, this approach has shown significant improvements and
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