Traction Electric Drive with the Field Regulated Reluctance Machine

Abstract

The field regulated reluctance machine is the future for automotive transport electric drives. In this machine, stator current is switched in the function of a rotor position. The massive salient rotor of the electric machine does not contain windings. The stator is fulfilled in the body and iron of the serial ac induction motor. The stator winding sections, which positioned over interpolar space, serve as an excitation winding and others sections, which positioned over the rotor poles, the role of an armature winding. In most cases, the optimal winding current waveform is distinct from the sine waveform. The ideal rectangular waveform is used for a case of separate current sources for each phase. At the rotation of the motor, each stator section winding pass from the “excitation” zone to the “armature” zone. The stator has a finite number of phases. If the stator currents are switched, the part phase, in which there is a switching of an armature current, is in a zone of excitation, and another - in a zone of an armature. It causes additional losses in the rotor, because the rotor is fulfilled massive (not laminated). To calculate the losses first of all it is necessary to determine the factors, which impact their value, and then, to estimate the degree of influence each of them has on the switching losses value. Such factors include the form of the stator core, the form of the current in phase windings, and the number of stator winding phases. The calculation of losses is executed by the method of winding functions. The experimental data is provided from a breadboard model of the 20kW drive.