| 摘要 |
PURPOSE:To phase-control a motor in order to control the quantity of combustion air by a method wherein the peak value of the supply voltage applied to the motor is detected in order to calculate the correction of phase in respose to the variation of the detected peak values. CONSTITUTION:The positive half wave of power source 11 is divided its voltage by resistances 14 and 15 after passing through a diode 13 and inputted to an integration circuit composed of a resistance 17 and a capacitor 18 in the form of the resultant divided voltage. In this case, the detection of the peak value of the half wave of voltage is performed after the elapse of a proper period of time (tm sec), during which the voltage reaches the peak value Vp, starting from the time, at which the voltage reaches the reference starting voltage Vt determined with respect to the positive half wave of the voltage. Further, the peak value of the supply voltage is led through an operational amplifier 19 to the plus side terminal of a comparator 20. Each ladder consisting of a ladder network 21 in a microprocessor unit 7 sequentially generates output stepwise as a scanner so as to obtain the point of congruity with the peak value of the voltage in every positive half wave in order to digitized the peak value and to calculate the correction in proportion to the supply voltage. A phase control circuit is controlled by being corrected with said calculated correction. |
