US 12,149,185 B2
Power conversion device
Yu Kawai, Tokyo (JP); and Kikuo Izumi, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Appl. No. 17/921,176
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed May 21, 2020, PCT No. PCT/JP2020/020120
§ 371(c)(1), (2) Date Oct. 25, 2022,
PCT Pub. No. WO2021/234910, PCT Pub. Date Nov. 25, 2021.
Prior Publication US 2023/0170826 A1, Jun. 1, 2023
Int. Cl. H02M 7/539 (2006.01); H02M 1/00 (2006.01); H02M 7/5387 (2007.01); H02M 7/5395 (2006.01)
CPC H02M 7/5395 (2013.01) [H02M 1/0006 (2021.05); H02M 7/53873 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A power conversion device comprising at least one circuit to receive a DC input voltage and perform power conversion, wherein
each of the at least one circuit includes
an inverter to receive the DC input voltage and generate an inverter voltage,
a filter to receive the inverter voltage and output an output voltage,
a detector to detect a DC component of the output voltage,
a feedback controller to receive an AC voltage command and the DC component and determine an inverter voltage command such that the DC component is equal to a target value, and
a PWM controller to receive the inverter voltage command and perform pulse width modulation control of the inverter,
the target value is zero or a value corresponding to an offset error of the detector, and
the feedback controller
computes a compensation amount for compensating for the DC component, and
determines, as the inverter voltage command, the AC voltage command on which a product of an absolute value of a sine wave and the compensation amount is superimposed, the sine wave being synchronized with a period of the AC voltage command.