| 摘要 |
PURPOSE:To reduce a detection ripple of detection of a half period width of an AC signal and to decrease a speed change by subtracting a value obtained by multiplying an inner signal value before one sampling time by a constant from a new error value at each sampling to obtain a new inner signal value, and adding the new value to the value before the one sampling time to form a control signal. CONSTITUTION:When speed detecting means 3 obtains a new error value at each sampling of a new detection signal (b), calculating means 5 of compensating means 4 subtracts a value obtained by multiplying an inner signal value before one sampling time by A (0<A<1) from the error value to obtain a new inner signal value. The new value is added to the inner value before the one sampling time to form a control signal Y. Thus, even if the influence of detection ripple of a rotary sensor 2 and a speed detector 3 is reduced, a feedback gain can be increased to obtain a desirable speed control performance. |
