Improved design for electric vehicle induction motors using an optimisation procedure

A design technique for electric vehicle (EV) induction motors using an optimisation procedure is described. The supply inverter operates in PWM mode with a field orientated controller in both the constant torque and the constant power regions. The motor voltage regulation strategies are discussed in the first part of the paper, because the motor design and the inverter kVA size are related to it. Thus, the nonlinear programming technique is applied for the three-phase induction motors designs in the design procedure. The proposed method has been applied to design a 17.5kW induction motor with 30kW maximum power. Complete design results for motors with different characteristics (voltage regulation strategy, pole number, base and maximum speeds) are presented and discussed.