| 摘要 |
PURPOSE:To simplify the titled circuit and to output a rapid and precise control signal by using a differential operator having proportional and integrating functions and the one having proportional and differential functions to decide the pulse duty ratio of the control signal. CONSTITUTION:The differential operator 18 having the proportional and integrating functions proportionally amplifies the difference between a voltage value corresponding to objective number of revolutions and the one corresponding to the real number of revolutions superposed by a ripple inputted by an f-V converter 16, integrates the difference and outputs voltage V1 including the ripple. The voltage output V1 including the ripple of the differential operator 18 and set voltage Vs corresponding to the objective number of revolutions are inputted to a differential operator 19 having proportional and differential functions, which outputs a pulse signal Vc having the same frequency as that of the ripple having the duty ratio corresponding to the difference between the voltage output Vi including the ripple of the differential operator 18 and the set voltage Vs by adjusting the amplification factors of proportion and differentiation, and when the difference is large, outputs a DC signal Vc having the duty ratio ''1'' or ''0''. |
