Harmonic Analysis and its Application in Traction Power Supply System Under Load Fluctuations

With the rapid development of railway transit system, harmonics of traction power supply systems under load fluctuations have become increasingly significant problem. Firstly, this paper summarizes the working principle of traction power supply system, and elaborates on the types and operating characteristics of the loads. And then the harmonic problems caused by the load fluctuations of traction power supply was analyzed in detail, which include the start-up and braking process of electric locomotives. And the impact of freight train operations on the power supply system was analyzed. Finally, electric locomotive model and traction power supply system were conducted based on the real power substation. The simulation results indicate that the harmonics caused by load fluctuations in traction power supply loads have a significant impact on both the power grid and the other loads nearby. The above studies provide theoretical basis for optimizing the design and harmonics control of traction power supply systems.