| 摘要 |
PURPOSE:To eliminate the adjustment of a firing angle after assembling by calculating the firing angle from the outputs of an up-down counter controlled in response to the deviation between a target value and a detected value and a repetition counter which counts the clock pulses in synchronization with an AC power source. CONSTITUTION:A comparator 21 compares a current instruction vi with a current feedback signal vf, and outputs ''H'' to the up-down terminal of an up-down counter 22 when vi>vf,''L'' to the up-down terminal when vi<vf and ''L'' to a stopper terminal when vi=vf. An up-down counter 26 reads out the output of the up-down counter 22 by the present signal synchronized with a power source, and then counts the clock pulses until a reset signal is given. A comparator 28 compares the output of the counter 26 with the set value a and outputs a pulse to a distributor 17. |
