Research On Electrical Compatibility Of PWM Encoder For Urban Rail Train

Due to the development of city and technology,the electromagnetic environment on urban rail train operation lines is more and more complex,which will cause electromagnetic interference to the complex and sensitive electronic devices on trains,and pose a serious threat to train running safety.For example,the PWM encoder on the EMU urban rail transit which exported to Brazil Rio De Janeiro by Changchun rail bus Limited by Share Ltd has electromagnetic interference.The train cannot operate normally and safely.Therefore,it is necessary to study the electromagnetic interference sources,the electromagnetic interference coupling mechanism and the electromagnetic interference suppression measures of the PWM encoder on EMU urban rail transit,so as to improve its electromagnetic compatibility.This paper is based on the background of PWM encoder electromagnetic interference Changchun rail bus Limited by Share Ltd exported to Brazil Rio De Janeiro.First of all,on the axis of the EMU urban rail transit terminal grounding mode,build train working grounding and grounding protection topology in Brazil,the scene of the train axle end protection grounding transient current test,combined with the PWM encoder output the internal circuit diagram of EMU urban rail transit,the internal components PWM the encoder output loss mechanism was analyzed;then based on the EMU urban rail transit shaft grounding protection test results of transient current test,in-depth analysis of the changes of rail transient current and the change of rail impedance,electromagnetic interference and coupling mechanism of train PWM encoder fault was analyzed and an experimental platform is set up to verify the electromagnetic coupling mechanism;finally,according to the relevant standard GB/T 17626?IEC 61000,EMC test of PWM encoder on EMU urban rail transit,a reasonable and effective electromagnetic interference suppression method is proposed,which achieves the desired effect of the suppression of electromagnetic interference,and proves the effectiveness of the electromagnetic interference suppression measures.