| 摘要 |
PURPOSE:To vary load currents continuously by controlling a Triac by a thyristor ignited by set pulses and a rectifying circuit rectifying a power supply of the inductive load and opening and closing a main thyristor by gate signals from the Triac. CONSTITUTION:The power supply RS of the inductive load 5 is made to a main circuit 1 and a control circuit 6, the thyristor 10 is ignited by pulses from a pulse setter 12, the gate signals of an output wave-form of a rectifier 8 are added, and the Triac for control is turned on while the gate signals are added to the gates G1, G2 of the main thyristors 2, 3. Consequently, the main thyristors 2, 3 are at on under a condition that is synchronized with a point of time of on of the thyristor 10 in the R phase and S phase of the same power supply. Accordingly, the inductive load can be on-off controlled digitally at every 1Hz regardless of line frequency. |
