An asymmetrical connection balance transformer-based power quality control system for electrical railway

In view of multifarious power quality problems in the electrical railway power system (ERPS), an asymmetrical connection balance transformer (ABT)-based power quality control system (ABT-PQCS) is presented in this paper. The back-to-back converter which is connected to the system through the step-down transformer can eliminate the negative sequence current (NSC), compensate reactive power at the same time. The passivity based control scheme which is designed by means of the equivalent circuit model of the loads significantly improves the system performance. The simulation results verify the effectiveness of the presented system, and shows that it is very suitable for the ERPS.