Study On Synchronous Reluctance Motor For Improving Force Index

The Synchronous Reluctance Machine (SynRM) is no winding and permanentmagnets in the rotor, with simple structure, and is strong and durable. Compared withthe Switch Resistance Motor, it has the advantages of the small torque ripple and noise.Compared with the Permanent Magnet Synchronous Motor, SynRM is lower cost, noweak magnetic field difficult and no loss magnetic of high temperature. But it exist theproblem of power factor low and small output torque.Based on the analysis of rotor structure, main features, operation principle ofSynRM, and its mathematical model in the dq coordinate system, it is found theSynRM only has reluctance torque, and no basic electromagnetic torque. Thedifference of the quadrature-axis and direct-axis inductance directly affect the motoroutput torque, and power factor associated with salient pole rate, high rate of salientpole can improve the power factor of the motor.The finite element method (FEM) is used to carry out motor electromagneticanalysis and structure optimization calculation in the Ansoft software environment.It iscalculated and analysised that the effects of the SynRM rotor rib width,rotor air layerratio,proportion,position and motor saturation on L_d, L_qelectromagnetic torque andpower factor.The analysis indicates that the air layer ratio and saturation which havemore impact on L_qand electromagnetic torque are the main parameters for theperformance of motor. And the influence of the air layer proportion and position on L_d,L_qand electromagnetic torque is not significant. The above conclusion provides thefoundation for getting the high performance SynRM．Finally, on account of the SynRM rotor structure features, the paper adopts that acertain amount of permanent magnetic material is added into the optimized rotor airlaye to further improve the motor output torque and power factor. The law is studiedthat the permanent magnet with different adding quantity, magnetic, and adding theposition of motor influence on L_d, L_q, electromagnetic torque and power factor. Resultsshow that the permanent magnetic material firstly ladded into air layer arm is moreefficient to improve the motor performance. When the rotor air laye is filled up byNdFeB N30SH, the motor electromagnetic torque is increased by76%relative to theprototype, by55%relative to the optimized prototype, and the power factor is0.95, butthe cost of permanent magnet materials is3000yuan; When the rotor air laye is filled up by ferrite Y35, motor electromagnetic torque is increased by43%relative to theprototype, by26%relative to the optimized prototype, and the power factor is0.92. Thecost of the permanent magnet material is only120yuan. The study provides thereference value for the design of permanent magnetic material which is added intoSynRM．...