Research on Life Evaluation Method for DC Capacitors of Battery Chargers for Electric Multiple Units
The battery charger is the core link of the DC power supply system of the electric multiple units(EMUs),and the DC capacitor is a key component of the battery charger.Accurate evaluation of the life state of the DC capacitor is of great significance to the fault prediction and reasonable maintenance process arrangement of the battery charger.Ai-ming at this problem,this paper studied the influence of different failure modes on the degree of capacitor degradation and the corresponding failure criteria by analyzing the failure mechanism of the DC capacitor of the battery charger.On this basis,a double-stress accelerated life model of the DC capacitor based on Arrhenius model was proposed.A series of accelerated life experiments were carried out based on different ripple currents and temperatures to verify the correctness of the proposed model.The errors between the actual failure time of the capacitor determined by accelerated life experi-ments and the theoretical failure time of the capacitor calculated by the double-stress accelerated life model are less than 8.7％,which verify the correctness of the proposed double-stress capacitive accelerated life model.Finally,a life evalu-ation method for the DC capacitor of the EMU battery charger was further proposed based on the double-stress acceler-ated life model for the DC capacitor,realizing the accurate life evaluation of DC capacitor of the EMU battery charger under actual operating conditions.
electric multiple units(EMUs)battery chargerDC capacitoraccelerated life modellife evaluatio
万方数据
维普
