US 11,757,394 B2
Motor control device and motor system
Takashi Oba, Utsunomiya (JP); and Reiji Yamasaki, Kawasaki (JP)
Assigned to MINEBEA MITSUMI Inc., Nagano (JP)
Appl. No. 17/627,746
Filed by MINEBEA MITSUMI Inc., Nagano (JP)
PCT Filed Jul. 6, 2020, PCT No. PCT/JP2020/026341
§ 371(c)(1), (2) Date Jan. 17, 2022,
PCT Pub. No. WO2021/014947, PCT Pub. Date Jan. 28, 2021.
Claims priority of application No. 2019-134650 (JP), filed on Jul. 22, 2019.
Prior Publication US 2022/0263449 A1, Aug. 18, 2022
Int. Cl. H02P 27/08 (2006.01); H02M 1/00 (2006.01); H02M 7/5387 (2007.01)
CPC H02P 27/08 (2013.01) [H02M 1/0009 (2021.05); H02M 7/53871 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A motor control device, comprising:
a control unit configured to generate a PWM signal corresponding to each phase of a motor including coils of a plurality of phases;
an inverter circuit configured to drive the coil of each phase, based on the PWM signal; and
a current detector connected to a direct-current line of the inverter circuit in series, wherein
the control unit includes
a current detection unit configured to detect a current of the current detector,
a duty cycle setting unit configured to set a duty cycle of the PWM signal of each phase, based on a detection result of the current detection unit, and
a PWM signal generation unit configured to generate the PWM signal of each phase, based on the duty cycle set by the duty cycle setting unit,
one cycle of the PWM signal of each phase includes a first period and a remaining second period,
the PWM signal of each phase has a signal level changing at a timing according to the set duty cycle in the first period, and has a signal level changing at a different fixed timing in the second period, and
the current detection unit detects a current of the current detector in the second period.