Patent ID: 11909307
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 6:
7. A power conversion device comprising:
a power converter including a plurality of arms, each arm including a plurality of sub modules connected in series, and
a control device to control voltages of the plurality of sub modules by PWM control using a carrier signal for each sub module,
the sub module including a plurality of switching elements, a power storage element, a pair of output terminals, and a bypass switch to bypass the sub module, wherein
the sub modules in the arm are categorized into a plurality of groups,
when the control device detects failure of the sub module in the arm, the control device stops the switching operation of the plurality of switching elements included in a sub module belonging to a first group, sets a phase of a carrier signal of a normal sub module belonging to the first group so as to equalize intervals among phases of carrier signals of a plurality of normal sub modules in the arm, and restarts the switching operation after setting the phase of the carrier signal of the normal sub module belonging to the first group, and
after the switching operation is restarted, the control device stops the switching operation of the plurality of switching elements included in a sub module belonging to a second group, sets a phase of a carrier signal of a normal sub module belonging to the second group so as to equalize intervals among phases of carrier signals of a plurality of normal sub modules in the arm, and restarts the switching operation after setting the phase of the carrier signal of the normal sub module belonging to the second group.