Research on Permanent Magnet Synchronous Motor Used as Air Conditioner Compressor

　　Research on Permanent Magnet Synchronous Motor Used as Air Conditioner Compressor
　　Presently, induction motor is mostly used for frequency-change air conditioner compressor, but it has such drawbacks as low efficiency and complicated controller. Compared with the induction motor, PMSM (permanent magnet synchronous motor) has advantages as high efficiency and energy-saving, compactness and premium properties for speed adjustment. So PMSM is perfect substitute for the driving motor of the conditioner compressor. Different arrangement of magnet has different distribution of flux; it will affect the performance of the motor. So it is Neodymium Magnets meaningful to contrast the performances of PMSM which has different structure of rotor.The distribution of the air-gap magnetic field influence many performances of the PMSM. And the magnetization of PM (permanent magnet) and the magnetic pole shape of the rotor determine the air-gap magnetic field. In order to improve the dynamic performance and minimize torque ripple, this paper investigates the post-assembly magnetization of PM and the optimization of magnetic pole shape of PMSM.Firstly, it has selected five different representative structures of the rotor which are used in air conditioner compressor and designed motors with same stator parameters. The FEM (finite element method) model is established and calculated. Then the performances of the motors which have different structure of rotor are contrasted. The motor which has optimum performance is selected. Then on the base of theoretical analysis of magnetic path of post-assembly magnetization, post-assembly magnetization of five motors which have different http://www.999magnet.com/products/110-sintered-neodymium-magnets structures of rotor is operated using one phase winding. The results of the magnetization are contrasted.According to the contrastive results and practical situation, the motor which has relative premium properties is selected. Then rotor structure and parameters are same, fractional slot winding is used. Performance of the motor which has fractional slot winding is compared with the original motor’s. Simulation result proves that torque ripple is considerably reduced.Lastly, it optimizes magnetic pole shape to minimize the torque ripple