Developing Electromagnetic Field Software Of Traction Motor Based On ANSYS

Electric locomotive traction drive system plays the important role due to the rapid development of China's high-speed railway,and the key technology about the attachment such as traction motor has also improved quickly.The faster the train run,the more reliable the traction motor needs.There are many different kinds of traction motor to match the different electric locomotives,the motor designers need to design special programs corresponding to the special traction motor.It wastes lots of time in the traditional design method.Maybe the result is not accurate.In order to solve this problem,This paper focuses on the following study fields:Firstly,An asynchronous traction motor field-circuit mathematical model was developed based on FEM.According to theory of electromagnetic,this paper described the process of the finite element method and analyzed the field-circuit mathematical model in ANSYS,then build the field equations coupled with circuit on the asynchronous traction motor,which provides the theory of the development of the software.Secondly,this paper develop a special software package for electromagnetic field analysis of asynchronous traction motor,which dedicated to ANSYS.In view of the high-power traction motor design,the paper use UIDL language to write the humanized interactive interface,Then it use APDL language to write the traction motor transient electromagnetic field analysis program and sinusoidal eddy current field analysis program based on the field-circuit coupling method,the finite element method of electromagnetic field analysis on traction motor will be obtained by UIDL interface to call APDL function models.After composing the interface and function models,the electromagnetic field calculating platform about traction motor based on ANSYS will be complete.Thirdly,calculating the electromagnetic field on a typical traction motor which is provided by company in this platform,magnetic flux distribution,rotor bar current density,the stator-side current curves will be obtained in a variety of situations include load condition.Air gap flux density curve and the diagram of the harmonic content and electromagnetic torque on slip curve will also be obtained by processing the data of the flux density and electromagnetic torque data in each time-step.The analyses are basically consistent with the experimental data,which prove the reasonableness of the application of this program package for electromagnetic field analysis,Lastly,taking advantage of the filed circuit coupling in ANSYS,the finite element model of asynchronous traction motor with broken bars was constructed in this electromagnetic field calculating platform function model.Analyzing the difference on distribution of magnetic field on different situations,the 3^th harmonic component of air gap flux density and current in bars,the electromagnetic torque under rated load before and after broken bars fault,the fault feature is very obvious.Comparing to the electromagnetic field calculating results with theoretical basis,it provided that the field-circuit coupling model of asynchronous traction motor with broken bars in this platform can accurately simulate the electromagnetic transient fault conditions of asynchronous traction motors.And it lays the foundation in asynchronous traction motor fault diagnosis and optimal design.