定转子结构对集中绕组永磁电机中二倍频径向电磁力的影响分析

Aiming at the reduction of two-time frequency electromagnetic force in permanent magnet (PM) machines with concentrated windings, the methods of stator permeance bias and rotor harmonic injection were proposed. First, the theoretical model of two-time frequency electromagnetic force in PM machines was proposed and the magnetic field regulation effect and the influence of various order force waves on vibration were analyzed based on the electromagnetic field theory and finite-element analysis (FEA). Moreover, the stator topology was modified by the proposed rotary auxiliary slot and the stator permeance bias factor is introduced, which significantly weakens the amplitude of the 3^rd order force wave and hence; Meanwhile, with PM slot edge shaping proposed, the electromagnetic force harmonic injection is achieved, which is effective for the 6^th order force wave reduction. Finally, the prototype was built and tested via machine vibration, compressor noise, and air-conditioning system noise tests to verify effectiveness of proposed stator permeance bias and rotor harmonic injection topologies on two-time frequency noise improvement in compressors.