Research on interpolar leakage coefficient of PMSM with variable magnetic reluctance in the exciting circuit

Permanent magnet synchronous motor (PMSM) driving system used in electric vehicles get a lot of development in recent years. A PMSM with variable magnetic reluctance in the exciting circuit by the movable permanent magnet in permanent-magnet slot is presented. Flux weakening is accomplished by reduction of effective magnetic flux area provided by permanent magnets duo to the variable magnetic reluctance. The special rotor structure and flux weakening principle are introduced. No-load interpolar leakage coefficient is link to the usage of permanent magnets, demagnetization ability and flux weakening speed range. While flux weakening of this new PMSM doesnpsilat lie in demagnetization armature reaction and the no-load interpolar leakage coefficient design method is different from the general PMSM. From four aspects of air-gap length, magnetic bridge size, permanent magnets size and motion to research on the no-load interpolar leakage coefficient. Calculation result is corresponding with analysis and laid the foundation on the design and analysis of this new PMSM.