US 12,273,065 B2
Motor control device and electric pump device
Yasuhiro Shirai, Kanagawa (JP)
Assigned to NIDEC POWERTRAIN SYSTEMS CORPORATION, Kanagawa (JP)
Filed by NIDEC POWERTRAIN SYSTEMS CORPORATION, Kanagawa (JP)
Filed on Jun. 26, 2023, as Appl. No. 18/340,895.
Claims priority of application No. 2022-106336 (JP), filed on Jun. 30, 2022.
Prior Publication US 2024/0007028 A1, Jan. 4, 2024
Int. Cl. H02P 6/182 (2016.01); H02P 6/15 (2016.01)
CPC H02P 6/153 (2016.02) 6 Claims
OG exemplary drawing
 
1. A motor control device that controls a three-phase motor, the motor control device comprising:
a drive circuit that converts DC power supply voltage into three-phase AC voltage and supplies the three-phase AC voltage to the three-phase motor;
a first voltage detection unit that detects terminal voltage of three phases of the three-phase motor; and
a control unit that detects a point at which a first voltage value, which is a detection value of the terminal voltage, intersects a predetermined zero-cross determination level as a zero-cross point, and controls the drive circuit based on a detection result of the zero-cross point,
wherein the control unit corrects the first voltage value by multiplying the first voltage value by a first coefficient inversely proportional to an output duty ratio with respect to the three-phase motor in a case where the output duty ratio is equal to or less than a predetermined threshold.