Patent ID: 11901851
Assignee: MINEBEA MITSUMI IN.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 16:
17. A motor drive control method performed by a motor drive control device including a control circuit configured to generate a drive control signal being a PWM signal for driving a motor including a coil of at least one phase, and a drive circuit including a high side switch and a low side switch, the high side switch and the low side switch being connected in series to each other and provided to correspond to the coil of each phase of the motor, the drive circuit being configured to alternately turn on and off the high side switch and the low side switch according to the drive control signal to switch an energizing direction of the coil of the corresponding phase, the motor drive control method comprising:
a first step of determining, by the control circuit, a target point of zero crossing of a coil current of a predetermined phase based on a position detection signal synchronized with an induced voltage of the coil of the predetermined phase of the motor and corresponding to a rotational position of a rotor of the motor;
a second step of estimating, by the control circuit, a zero crossing point of the coil current of the predetermined phase by detecting a change in a current direction of the coil current of the predetermined phase at a predetermined timing in every cycle of the PWM signal;
a third step of generating, by the control circuit, at least one of a phase adjustment instruction signal for instructing phase adjustment of the coil current and a frequency adjustment instruction signal for instructing frequency adjustment of the PWM signal according to a phase difference between the target point determined in the first step and the zero crossing point estimated in the second step such that the phase difference is within a predetermined range; and
a fourth step of generating, by the control circuit, the drive control signal based on the determination result of the third step.