US 12,341,448 B2
Power conversion device
Kazuaki Tobari, Tokyo (JP); Yuta Iwase, Tokyo (JP); and Yoshiyuki Taguchi, Tokyo (JP)
Assigned to Hitachi Industrial Equipment Systems Co., Ltd., Tokyo (JP)
Appl. No. 18/274,509
Filed by Hitachi Industrial Equipment Systems Co., Ltd., Tokyo (JP)
PCT Filed Jan. 24, 2022, PCT No. PCT/JP2022/002487
§ 371(c)(1), (2) Date Jul. 27, 2023,
PCT Pub. No. WO2022/239307, PCT Pub. Date Nov. 17, 2022.
Claims priority of application No. 2021-082831 (JP), filed on May 14, 2021.
Prior Publication US 2024/0097589 A1, Mar. 21, 2024
Int. Cl. H02P 21/24 (2016.01); H02P 21/18 (2016.01); H02P 27/06 (2006.01)
CPC H02P 21/18 (2016.02) [H02P 21/24 (2016.02); H02P 27/06 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A power conversion apparatus comprising:
a power converter that outputs a signal to a motor that changes an output frequency, an output voltage, and an output current of the motor;
a control unit that controls the power converter;
wherein the power converter is configured to calculate:
a first power from the output voltage and the output current;
a second power from the output current, electrical circuit parameters, and frequency estimates;
wherein in order that the first power follows the second power, in a low speed region, a first phase error estimation value, which is a deviation between a control phase and a magnet phase of the magnet motor, is calculated, in a medium-high speed range, a second phase error estimation value, which is a deviation between the control phase and the magnet phase of the magnet motor, is calculated, a deviation between the first phase error estimation value or the second phase error estimation value and a phase error command value is input to a proportional integral control unit so that the first phase error estimation value or the second phase error estimation value follows the phase error command value.