摘要 |
PURPOSE:To quicken response of a current control system for a transient state, where current varies abruptly, by providing means for estimating the current in the winding of a motor which is not detectable as a DC current and means for initializing the estimating means, thereby initializing the estimating means with a signal produced at every period of commutation. CONSTITUTION:A commutation trigger 10 is provided with a pulse signal at a repeating period, and an initializing transistor TR3 is conducted to discharge a capacitor C1 through a resistor R5 to zero level. Simulation current is initialized through discharge of the initializing transistor TR3 by setting the resistance of the resistor R5 considerably lower than that of the discharge resistor R2 in a peak hold circuit 1. By such arrangement, controllability of transient response, occurring at a repeating period, can be improved according to an average current control. |