Control Strategy for a Variable Winding Synchronous Reluctance Machine for Traction Applications

This paper presents a control algorithm for a synchronous reluctance machine with different windings. Due to the poor saliency ratio of the SynRM the use of field weakening alone limits the constant power speed range. In this work the machine uses two different windings, one with 18 turns and the other with 25 turns. The constant power speed range of the machine was extended by 76% when the windings were changed from 25 turns to 18 turns. The control algorithm implements field weakening before the windings are changed. When the machine winding configuration is changed constant power speed range can further be extended. Ideally the machine winding would be changed automatically by the use of power switches, however in this paper due to the unavailability of the power switches the machine windings were changed manually.