Star-point changeover for permanent-magnet synchronous motors

Abstract:
Due to their high torque density, permanent-magnet synchronous motors with water cooling are increasingly used in main drives. For reasons of costs, the question arises how to design the main drive with the smallest possible converter power stack. If a field-weakening is not possible, the lesser-known star-point changeover is an alternative. The circuit concept as well as the winding technology in case of distributed integer-slot windings is presented. With the help of the star-point changeover it is possible to switch from full- to part-winding operation. The stationary operating behavior of permanent-magnet synchronous motors with full- and part-winding is discussed by means of a 2-pole spindle.