A Novel Motor Modelling Method for Reluctance Motor Electric Vehicle Drive Systems

The field of electric vehicles is one of the most popular research topics today. These vehicles require highly efficient and cost-competitive drive system solutions due to the increasing competition. The reluctance motor drive systems are excellent candidates for fulfilling these requirements However, the controlling of these drive systems is difficult as they represent a heavily nonlinear behavior due to the varying stator inductances. The stator inductances are changing both in the function of the stator currents- and that of the rotor position. This phenomenon makes it necessary to apply advanced modelling solutions that provide a more precise motor model for the torque control algorithm. This paper presents a novel motor modeling method for the reluctance motor drive systems. A new type of inductance matrix is derived, which is a critical part of the motor model. This inductance matrix is used to define new relationships for the electromagnetic torque and the phase voltages of the machine for a given stator current, leading to a novel motor model. This new motor model can serve as an input for the torque control algorithm research and development activities.