Design of active filters for dynamic damping of harmonic currents generated by asynchronous drives in modern high power locomotives

In order to reduce the harmonic contents of the currents injected in an overhead traction line while minimizing the electromagnetic interference with the signaling system, the use of an active filter seems to give marked advantages. The authors analyze a reliable active filter design, applied to a high-power, high-speed locomotive. The configuration, mainly derived from existing applications of harmonic power filters for industrial plants, was simulated and investigated, especially from the viewpoint of the dynamic behavior