Patent ID: 9000708
Filing Date: 2015-04-07
Classification: G05B,H02P

Abstract:
1. A motor control circuit in which a detection signal of a frequency that is proportional to a speed of a motor is input from a speed detection means attached to the motor, a reference signal having a frequency corresponding to a target speed is input from outside, and a period of the detection signal and a period of the reference signal are compared to variably control a speed of the motor, the motor control circuit comprising: a period error signal output means that outputs a period error signal corresponding to a difference between the period of the detection signal and the period of the reference signal; a speed error signal output means that outputs a speed error signal obtained by multiplying the period error signal by a speed gain; and a gain correction means that uses a ratio of a correction reference period relative to the period of the reference signal as a correction amount, and squares the correction amount and multiplies it by a predetermined speed gain of the speed error signal output means to correct the predetermined speed gain.