| 摘要 |
PURPOSE:To compensate quickly the voltage fluctuation by storing the conducting arm of a self-exciting converter when a power system has a fault and starting the conduction at the conducting arm when the fault of the system is recovered to ensure the restarting quickly. CONSTITUTION:When a system fault is detected, three ignition pulse signals delivered from a firing angle controller 10 are blocked by an NOR circuit 14. Thus the output signal of an inverter 30 is set at a high level. While a flip-flop 18 receives the output signal of the inverter 30 and obtains an output of a low level. The inputs of a memory flip-flop are all set at high levels and their preceding signal levels are stored. When the system fault is released, the output of a memory flip-flop 24 is kept at a low level showing a fault state. The output of the flip-flop 24 is set at a high level when an ignition pulse of an arm same as a fault mode memory arm is produced. Thus the lock of the flip-flop 24 is released, and all flows of signals become normal. |
