US 12,088,228 B2
Power conversion device and control method thereof
Yusaku Onuma, Tokyo (JP); and Takuya Sugimoto, Tokyo (JP)
Assigned to Hitachi Industrial Equipment Systems Co., Ltd., Tokyo (JP)
Appl. No. 17/911,175
Filed by Hitachi Industrial Equipment Systems Co., Ltd., Tokyo (JP)
PCT Filed May 8, 2020, PCT No. PCT/JP2020/018609
§ 371(c)(1), (2) Date Sep. 13, 2022,
PCT Pub. No. WO2021/224976, PCT Pub. Date Nov. 11, 2021.
Prior Publication US 2023/0104331 A1, Apr. 6, 2023
Int. Cl. H02P 27/08 (2006.01); H02M 7/537 (2006.01)
CPC H02P 27/085 (2013.01) [H02M 7/537 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A power conversion device that controls driving of a three-phase motor by converting a DC voltage into a voltage based on a voltage command by an operation of a switching circuit, the device comprising:
a DC voltage detector that detects the DC voltage;
a norm generator that generates a voltage command norm from the voltage command;
a modulated wave generator that generates a first modulated wave from the detected DC voltage and the voltage command norm; and
a control signal generator that generates a control signal for controlling the operation of the switching circuit from the first modulated wave and a carrier wave,
wherein the modulated wave generator generates, for one phase at the timing of the maximum or minimum value of the voltage command, the first modulated wave having a magnitude of ½ of the detected DC voltage, and generates, for the remaining two phases, the first modulated wave having a magnitude based on the detected DC voltage and voltage command norm.