DEVICE FOR PROTECTING DISTRIBUTION LINE SIGNAL INJECTING DEVICE FROM TRANSIENT SURGE VOLTAGE

摘要

PURPOSE:To prevent the oscillation of a transmitter from being disabled with a transient surge voltage generated when the transmitter is connected to a high voltage distribution system by providing a switch short-circuiting the transient surge voltage generated to a secondary side circuit at application of power. CONSTITUTION:The primary side circuit is resonated to a frequency higher than the signal frequency by a low voltage capacitor 2 and a reactor 3. The secondary side circuit is resonated to the signal frequency by a high voltage capacitor 4 and an injected impedance 5. They are coupled by a two-winding coupling reactor 1. Further, a series inverter consists of a DC power supply 6, thyristors 7, 8 and diodes 9, 10. The switch 11 is provided to the high voltage side and a switch 15 is provided at the low voltage side. Then the transient surge voltage generated at the low voltage side of the reactor 1 by the application of the switch 11 is short-circuited by the switch 15. Then the switch 15 is turned off at several cycles after the transient surge voltage reaches a steady-state voltage, and the switch 12 is turned on to start the oscillation.