AC-DC CONVERTER, APPARATUS FOR CONTROLLING THE SAME AND DC POWER TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To stop continuation or protection of operation in order to prevent continuation of a fault and generation of damages to a device, by structuring a voltage type self-excitation type AC-DC converter through parallel provision of a self-extinguishing semiconductor element and an arc controllable semiconductor element. SOLUTION: A voltage type self-excitation AC-DC converter 3 is formed of a 6-phase or 12-phase bridge circuit in which the self-extinguishing semiconductor element 4 and arc controllable thyristor element 4c are connected inversely in parallel in each arm, and it is then connected to an AC system 1 via a transformer 2 for converter. A DC voltage detector 9 detects a DC voltage and is then inputted to a DC shortage voltage relay 10 to monitor the DC voltage. If a DC voltage is proved to be insufficient in such monitoring, a control pulse of the voltage type self-excitation AC-DC converter 3 is controlled with the controller 11. As a result, continuation and protection of operation is stopped, so that continuation of fault and damages to device are no longer generated.