A Hybrid Active Power Filter for Electric-Railway Systems using Multi-Level Inverters

A Hybrid Active Power Filter for Electric-Railway Systems using Multi-Level Inverters

* ** ** **

Kim, Yoon-Ho Kim, Soo-Hong Rho, Sung-Chan Lee, Kang-Hee

--- ABSTRACT

This paper proposes transformerless power conversion system consisting of a single-phase diode rectifier and a shunt hybrid filter for the electric-railway system. The hybrid filter consists of a single tuned LC filter per a phase and a low-rated NPC type multi-level inverter. Compared with conventional active filters. Transformers are not used. Also, LC filter works as not only a harmonic filter tuned at the 5th harmonic frequency but also a switching-ripple filter. The rating of the active filter can be decreased by using a NPC type multi-level inverter.

The simulation results confirm the validity of the system

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Power System Inductance Ls 0.3 mH

Filter Capacitor 195.4 uF

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