Multilevel inverter having voltage dividing capacitors distributed across multiple arms

摘要

The power converter of the invention relates to a small-sized highly efficient power converter for generating an a.c. voltage output of multiple levels with less harmonic content. In the power converter, a d.c. voltage source is separated into plural sections by series connected voltage dividing capacitors and multiple levels of a.c. output voltage are obtained from the divided d.c. voltage by on-off control of switching devices. The power converter has plural sets of the voltage dividing capacitors disposed separately adjacent to each switching devices, and series connection point of each set of the voltage dividing capacitors are connected to division points of the corresponding switching devices of each phase. The voltage dividing capacitors are connected with each other at their series connection points. Thereby, the arrangement makes wiring length short and equal between the switching devices and the voltage dividing capacitors for each phase and reduce a loss in the snubber circuit, resulting in an a.c. voltage output with less harmonic content.