Analysis of energy consumption characteristics and energy-saving technologies for traction system of metro trains

As metro construction expands in scale, the energy consumption of metro trains has been rising year by year, underscoring the importance of analyzing the factors that affect train energy consumption and developing energy-saving measures. Based on data of metro trains such as operational energy consumption and passenger flow, this study analyzed the energy consumption characteristics of train traction by considering various dimensions, including passenger loads, average station spacing, workdays and holidays, and seasonal changes. By combining simulation calculations of system energy consumption, the impact of different loads and station spacing on train energy consumption was examined, providing a reference for the energy-efficient operation of metro trains. The results showed that, at a constant travel speed, energy consumption per kilometer of train operation increased with rising load, while energy consumption per ton per kilometer first decreased and then increased. Shortened station spacing led to higher energy consumption per ton per kilometer of train operation. Additionally, temperature was found to significantly impact auxiliary energy consumption. Based on the analysis of factors affecting train energy consumption, this study explored energy-saving technologies in various areas, such as traction systems, auxili-ary systems, and vehicle-ground coordination. Case studies demonstrate that, under good energy feedback conditions, permanent magnet traction technology achieves a train energy consumption reduction by about 30%. Furthermore, with the additional support of bidirectional converters and energy utilization control technologies, system energy consumption decreased by more than 6%, reflecting the efficient utilization of energy flow from the power supply to the vehicles. The study findings provide a technical reference for improving metro operation modes and optimizing the design of metro trains in terms of energy savings.