High-voltage bi-directional DC-DC-converter for advanced electric locomotives

Existing DC current high power locomotives at standard input voltages of 3 kV, 1.5 kV, or 0.75 kV can be connected to high-voltage catenaries operated at n-times the DC voltage level via a novel n-cell capacitor switching converter. Each cell voltage is defined by the locomotive power train DC input level, thus balancing of capacitor voltages is not required.