Power conversion device having a frequency of a first control signal higher than a frequency of a second control signal

A power conversion device that converts power between a DC circuit and an AC circuit, the power conversion device comprising:

• a plurality of leg circuits connected in parallel between a first DC terminal and a second DC terminal and electrically connected to the AC circuit, each of the plurality of leg circuits including:
• at least one first converter cell;
• and
• a plurality of second converter cells other than the at least one first converter cell,
• each of the at least one first converter cell and the plurality of second converter cells including a capacitor and a plurality of semiconductor switching elements,
• a first control signal that controls switching of each of the semiconductor switching elements included in the at least one first converter cell being higher in frequency than a second control signal that controls switching of each of the semiconductor switching elements included in each of the plurality of second converter cells,
• wherein the at least one first converter cell is identical to the plurality of second converter cells in type, the type including a half bridge type, a hybrid type, and a full bridge type.

A power conversion device that converts power between a DC circuit and an AC circuit, the power conversion device comprising:

• a plurality of leg circuits connected in parallel between a first DC terminal and a second DC terminal and electrically connected to the AC circuit, each of the plurality of leg circuits including:
• at least one first converter cell;
• and
• a plurality of second converter cells other than the at least one first converter cell,
• each of the at least one first converter cell and the plurality of second converter cells including a capacitor and a plurality of semiconductor switching elements,
• a first control signal that controls switching of each of the semiconductor switching elements included in the at least one first converter cell being higher in frequency than a second control signal that controls switching of each of the semiconductor switching elements included in each of the plurality of second converter cells, wherein
• the first control signal has a frequency higher than four times as high as a fundamental frequency of the AC circuit, and
• the second control signal has a frequency higher than three times and lower than four times as high as the fundamental frequency of the AC circuit.