Analysis and Study of the Influence on the Train Side Harmonic as a SMES Fabricated Into the EMU Converter System

Due to the dynamic performance and continuous function of superconducting magnetic energy storage (SMES), the SMES was fabricated into the electrical multiple unit (EMU) high-speed train traction converter system. The pollution of harmonic current from ac drive electric locomotives was an essential problem to analyze. To settle this problem, first, the influence of SMES technology in the current harmonic of train grid side was studied, in which the current analysis method was used and a harmonic suppression scheme was proposed. Next, the effects of harmonic frequency characteristics and amplitude characteristics on the current harmonic were analyzed, with adjusting the carrier frequency and increasing the leakage inductance of the traction transformer. Finally, the accuracy of the theoretical analysis method is verified by the simulation analysis and experimental verification. The results showed that the new type superconductivity technology proposed could optimize the train side harmonic current remarkably.