MODULAR MULTILEVEL CONVERTER AND SUBMODULE OF THE CONVERTER

摘要

Disclosed are a modular multilevel converter and a submodule thereof to provide a new submodule structure. The submodule of the modular multilevel converter includes: a first bidirectional switch; a second bidirectional switch; a capacitor; a first terminal; a second terminal; and a third bidirectional switch. Each of the first bidirectional switch and the second bidirectional switch includes a switching device and a diode connected in anti-parallel with the switching device and is connected in series in an identical direction. The capacitor is connected in parallel with the whole of the first bidirectional switch and the second bidirectional switch which are connected in series. The first terminal is connected to a node to which the first bidirectional switch and the second bidirectional switch are connected while the second terminal is connected to a node to which the diode anode included in the second bidirectional switch and the capacitor are connected. The third bidirectional switch includes a switching device and a diode connected in anti-parallel with the switching device and is connected in the opposite direction to that of the second bidirectional switch in the path of applied direct current when the direct current is applied from the second terminal to the first terminal.