| 摘要 |
PURPOSE:To improve the follow-up propery of a pulse width modulation controller to a target value by inhibiting the pulse drive only when the control deviation is larger than the prescribed control deviation and the pulse width of the pulse drive circuit is larger than the prescribed drive pulse width. CONSTITUTION:An amplifier 2' without limiter amplifies a control deviation signal (d) between a motor position command signal (c) and a feedback signal (j), and applies an output signal (e) to a pulse width modulator 4. The modulator 4 controls a motor drive circuit 5, and supplies a pulse drive signal (h) to a motor 7. When a comparator 25 detects the fact that the control deviation signal (d) falls out of the prescribed range and a pulse width diagnosing circuit 24 detects that the pulse width of the pulse drive circuit (h) is larger than the prescribed pulse width, it sets a changeover switch 3 to the ground side by regarding as the defect of a hardware, and a switch 6 is opened to perform a protecting operation. |
