The Research Of Permanent Magnet Motor Eectromagnetic Design And Rotor Structure With Screw Compressor

Screw compressor, as a new generation of compressor is widely used in mining, chemicalindustry, energy and other industrial sectors, gradually replacing other types of compressors.Meanwhile, screw compressor consumes large amounts of energy in a lot of enterprises.Reducing the energy consumption of the compressor to achieve energy-efficient is the majorissue for many research institutes and enterprises to be solved. At present, many enterprisesreplace conventional motor with frequency conversion motor to drive the compressor andachieve some results. Now, most of the screw compressors driven by variable frequencyasynchronous motors have low efficiency and more complex frequency conversion control. Bycomparison, the permanent magnet synchronous motor with high power index, lowtemperature, better starting performance and high efficiency at light loads, is an ideal drivingmotor of screw compressor in the future. In this paper, the development of the compressormotor is briefly introduced, what’s more, the45kW and4000revolutions per minutepermanent magnet synchronous motor with screw compressor is studied.Firstly, according to the practical operation of the permanent magnet synchronous motor(PMSM) used in screw compressor. PMSM schemes of three different pole-slot combinationsare designed, which are8-pole48slots,6-pole36slots and4-pole24slots. Through the studyof comparison and analysis of its performance, determining the poles number of PMSM.Secondly, the performance of the selected poles number of PMSM is studied further. Theparameters of schemes for PMSM with different slot-pole combinations, rotor structure, gaplength and the inside diameters of the stator are analyzed, ultimately determining theparameters of the rotor structure of the PMSM with screw compressor.Then, using ANSYS finite element software to analyze the PMSM rotor structuremechanical strength. By comparison with calculation results of rotor stress distribution,analyzing the key factors affecting the rotor structural strength. Choosing the optimal structureaccording to the calculation results of the stress distribution on the rotor structure, ensuring themotor safety and reliability from the structure.Finally, by using Solidworks and ANSYS software, the whole screw rotor dynamicanalysis model is established. Through analyzing the screw rotor dynamic characteristics, the natural frequency and vibration mode of the rotor are obtained.