| 摘要 |
PROBLEM TO BE SOLVED: To prevent the speed of rotation of a motor from being changed, to cancel a speed deviation even in a mode that a reference phase used to adjust the rotation phase of the motor does not exist, and to improve speed leading-in response by a method wherein, when a phase error is larger than a prescribed amount, a rotation reference phase is created according to a phase detection signal. SOLUTION: A comb filter part 22 creates a filter output signal in which the rotation cycle component of a motor and its harmonic component are removed from a speed-error signal from a speed-error creation part 21. A reference-phase creation part 25 creates the rotation reference phase of the motor according to the target rotational speed of the motor. A phase-error creation part 24 creates a phase-error signal according to the phase difference between a rotation reference phase and a phase detection signal. A synthesis part 23 creates a control signal according to the filter-output signal and the phase-error signal. Then, the reference-phase creation part 25 creates a rotation reference phase according to the phase detection signal when the phase-error signal is larger than a prescribed amount. Thereby, it is possible to obtain a VTR whose responsivity is excellent. |
