The Analysis Of Permanent Magnet Synchronous Traction Motor's Running Characteristic

Traction motor is one of the key components of track traction power transmission systems.PMSM has high power factor,high efficient, and big power densities,which is an ideal traction motor.Currently in the electric cars it has tremendous development.PMSM for track traction currently at home and abroad, has been widely used. This paper mainly include permanent magnet synchronous traction motor ontology of design and operation characteristic analysis.Mainly include the following content:First of all, on the base analysising domestic and international subway with traction motor currently.This paper tries to put forward the main contents.Secondly, permanent magnet synchronous traction motor used in the subway traction field, some key technologies shouled be researched to meet the special requirements. In order to obtain a good solt/pole combination, through comparing the performance parameters with different motor scheme of motor,a better solt/pole is selected. In order to obtain larger torque density and good Flux-weakening capability, through analyzing different structure of rotor, the optimal structure is choosed. In order to optimize air-gap flux density waveform, through optimize the motor rotor shape with eccentric structure. For the special working environment and insulation class, through the thermal load test, a appropriate thermal load value is picked. Considering the safety operation of electric motor, short-circuit current is researched, a PMSM for metro is designed by field-circuit coupled methodBesides,motor reactance is an important index of operating performance and torque output. The reactance parameters change as motor operating conditions.It is inaccurate in reflecting the essence of motor parameters with rated conditions.This paper adopted the method of equivalent D-axis State and equivalent Q-axis State to compute D-axis reactance and Q-axis reactance.Some of PMSM are tested to get the reactance value,which is contrasted with the calculated value. Finally, because the permanent magnet traction motor running conditions is complex, the operation performance of motor both in high and low speed require a comprehensive consideration.The equivalent circuit method and finite element method are used to for simulate the motor performance.Through the test,the simulation results are compared with the test result.