US 12,113,467 B2
Power conversion system and motor control method based on same
Yusuke Uei, Tokyo (JP); Takuya Ishigaki, Tokyo (JP); Hideto Takada, Tokyo (JP); Yutaka Matsumoto, Tokyo (JP); and Masaki Sugiura, Tokyo (JP)
Assigned to Hitachi Industrial Equipment Systems Co., Ltd., Tokyo (JP)
Appl. No. 17/791,413
Filed by Hitachi Industrial Equipment Systems Co., Ltd., Tokyo (JP)
PCT Filed Oct. 22, 2020, PCT No. PCT/JP2020/039782
§ 371(c)(1), (2) Date Jul. 7, 2022,
PCT Pub. No. WO2021/140723, PCT Pub. Date Jul. 15, 2021.
Claims priority of application No. 2020-001962 (JP), filed on Jan. 9, 2020.
Prior Publication US 2023/0029493 A1, Feb. 2, 2023
Int. Cl. H02P 27/00 (2006.01); H02P 21/18 (2016.01); H02P 21/20 (2016.01); H02P 27/08 (2006.01)
CPC H02P 27/08 (2013.01) [H02P 21/18 (2016.02); H02P 21/20 (2016.02); H02P 2201/09 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A power conversion system comprising: a power conversion device configured to supply electric power to a motor; and a power supply device configured to supply electric power to the power conversion device,
wherein the power conversion device includes:
a power conversion unit configured to convert the electric power;
a control unit configured to control the power conversion unit; and
a current detection unit configured to detect a current flowing through the power conversion unit,
wherein the power supply device includes:
a storage device configured to store electric power in accordance with a voltage;
a step-up/down power supply circuit configured to change the voltage of the storage device based on a voltage command; and
a computing circuit configured to compute energy stored in the storage device and output it as the voltage command to the step-up/down power supply circuit,
wherein the control unit calculates powered drive energy of the motor by using information from an encoder of the motor and a current value detected by the current detection unit,
wherein the computing circuit computes the energy stored in the storage device based on the powered drive energy calculated by the control unit, and
wherein when it is determined by the computation of the current value detected by the current detection unit, the information from the encoder, and the energy stored in the storage device that characteristics of the motor are restricted, the computing circuit temporarily changes the voltage command to increase the characteristics of the motor.