Research on new traction power system using power flow controller and Vx connection transformer

In order to solve the power quality problem and eliminate the neutral sections at exit of the traction substation, a new traction power supply system is proposed for the high speed and heavy haul railway, which adopts active power flow controller (PFC) and Vx connection transformer. The mathematical model of electrical transformation between three-phase power grid and single-phase traction load is built. Using the method of comprehensive compensation of three-phase unbalanced and reactive power, the operation current calculation of each port of new system is deduced. The topological structure and control strategy of PFC are discussed. By the simulation of the operating characteristics of the system proposed with different types of the traction load, the validity is verified by good performance.