US 12,249,933 B2
Motor control device
Akihiko Houda, Tsukuba (JP)
Assigned to ORIENTAL MOTOR CO., LTD., Tokyo (JP)
Appl. No. 18/253,001
Filed by ORIENTAL MOTOR CO., LTD., Tokyo (JP)
PCT Filed Nov. 9, 2021, PCT No. PCT/JP2021/041247
§ 371(c)(1), (2) Date May 15, 2023,
PCT Pub. No. WO2022/113732, PCT Pub. Date Jun. 2, 2022.
Claims priority of application No. 2020-196802 (JP), filed on Nov. 27, 2020.
Prior Publication US 2023/0421082 A1, Dec. 28, 2023
Int. Cl. H02P 21/24 (2016.01); H02P 21/22 (2016.01); H02P 27/08 (2006.01)
CPC H02P 21/24 (2016.02) [H02P 21/22 (2016.02); H02P 27/08 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A motor control device that controls an AC motor by sensorless control without the use of a rotor position detector, the motor control device comprising:
an inverter that converts a direct current to an alternating current based on a pulse width modulation signal;
a multilayer printed circuit board including an inner layer having a wiring pattern provided in a current line connecting the inverter to a winding of the AC motor;
a plurality of chip inductors mounted on a major surface of the multilayer printed circuit board in opposed relation to the wiring pattern with their coil directions coinciding with a predetermined direction crossing the wiring pattern, and connected in series to form a series circuit having a midpoint connected to a reference potential;
load resistors respectively connected between the midpoint of the series circuit and opposite ends of the series circuit;
a differential amplification circuit having a pair of input terminals respectively connected to the opposite ends of the series circuit; and
a control unit that estimates a position of a rotor of the AC motor by using an output of the differential amplification circuit, and generates a pulse width modulation signal to be supplied to the inverter according to the estimated rotor position.