| 摘要 |
PURPOSE:To prevent an intermittent current compensation circuit from disturbing a control system by monitoring the voltage across a thyristor for the firing interval thereby detecting an intermittent current. CONSTITUTION:When the voltage across a thyristor WA or ZB exceeds the forward voltage drop of thyristor during the firing interval of the thyristor WA or ZB, the thyristor WA or ZB turns OFF and judgment is made that the current is flowing intermittently. Consequently, output from a current control circuit 7 is amplified through an intermittent current compensation circuit 10 in order to compensate for the drop of gain in a control system caused by the intermittent current. Since the output is provided through a delay element in a primary delay or rate circuit 18 to a phase control circuit 12, the intermittent current compensation is carried out slowly for the control system without causing disturbance, and thereby response of the control system is not affected by the intermittent current. |
