Research on Control Strategy of Auxiliary Power Converter in Dual-Current Train AC/DC Conversion

Objective The start-stop control strategy for the auxiliary power converter（APC） under AC/DC conversion conditions of dual-current trains, and for train HAVC（heating, ventilation and air conditioning） system are studied, aiming to avoid APC overcurrent/overload failure and ensure train operation performance. Method Taking the dual-current train of the Tiaodeng to Jiangjin line in Chongqing as the research object, a reasonable APC stop and start strategy is formulated upon comprehensive consideration of ground beacon signals, APC working status and medium-voltage load working status. Specifically, when the train is about to enter the power-free area, the train HAVC load is stopped first, and then the auxiliary power supply is turned off. In addition, combined with APC working status and the medium-voltage load capacity, the matching relationship between APC and the medium-voltage load is analyzed, and a reasonable train HAVC system stop and start timing sequence is formulated. Result ＆ Conclusion The new strategy effectively solves APC overcurrent or overload fault problems during AC/DC conversion. At the same time, the new train HAVC system startup control strategy avoids the overcurrent or overload problems during APC startup process, significantly improving the train operation stability.