| 摘要 |
PURPOSE:To obtain a DC current switching circuit equipped with a GTO control circuit which can ignite and turn off the gate turn-off thyristor (GTO) surely only by low-level control input signals without a high-level separated power source. CONSTITUTION:When control input signals come between input terminals 1 and 2, oscillator circuit 5 is operated to generate a designed voltage in the secondary side of transformer 14, and a current is flowed through diode 6, capacitor 13 and the gate and the cathode of GTO 9, and GTO 9 is ignited to close the circuit between output terminals 3 and 4. At this time, thyristor 8 is held in a turning-off state. When control input signals disappear, the operation of oscillator circuit 5 is stopped; and when charging of capacitor 11 is stopped, thyristor 8 is ignited to flow the charge stored in capacitor 13 to thyristor 8 and the cathode and the gate of GTO9, and GTO 9 is turned off, thus opening the circuit between output terminals 3 and 4. |
