DC-Linked Feedback Compensated Shunt Active Harmonic Filter for Traction Power Supply Substation Medium Voltage Line

A modern DC electric railway traction power supply system consists of a twelve-pulse rectifier which will cause 11th and 13th order harmonics to be injected into the power system. A shunt active harmonic filter (SAHF) is proposed to mitigate the harmonics at medium voltage (MV) line. SAHF control strategy usually consists of three core elements which include reference current generation, DC-link feedback control, and current control and gate signal generation. This paper proposed a distinct time domain-based control strategy with DC-linked feedback reference current compensation method which has a simple topology, low mathematical complexity, and fast response time. Detailed performance analysis of SAHF is carried out in the parameter selection process whereby the effects of each parameter are discussed. The implementation of SAHF in traction power supply substation (TPSS) is simulated using MATLAB/Simulink. The harmonic analysis result has shown the effectiveness of the proposed SAHF in reducing THDv, TDDi, 11th order IHDi, and 13th order IHDi of TPSS MV line to levels lower than 4.61%, 1.03%, 0.96%, and 0.67% respectively which are compliant with the limits recommended by IEEE std. 519–2014.