摘要 |
PURPOSE:To prevent a motor from varying at its speed by reducing frequency transfer function from the variation in a load torque to the variation in the rotating speed of a motor in a specific frequency. CONSTITUTION:A speed detector 3 outputs a digital signal (b) in response to the period of an AC signal (a) output from a rotary sensor 2. A compensator 4 compares a speed detection value S corresponding to the signal (b) with a reference value Sref to obtain a rotary error E multiplied by R of gain. A calculated value V and the error E are added at a ratio of D:1 to obtain a control signal Y. The value V and the error E are added at a ratio of 1:1 to obtain an updated value and updated and stored as a new digital value M(I). Further, next new combined value V is obtained from the digital value group in a ram range. |