| 摘要 |
PURPOSE: To reduce the outside dimension and cost of a bidirectional GTO thyristor breaker by causing a GTO thyristor element group to self-break the current supply to the group when the magnitude of the current output of a DC current transformer is larger than a preset self-breaking current value. CONSTITUTION: When a forward current is made to flow to a bidirectional GTO thyristor, a DC current flows to a load side from a DC bus 18 through an anode-side forward diode group 12, GTO thyristor element group 11, and cathode-side forward diode group 13 and, when a backward current is made to flow to the breaker, the current flows to the DC bus 18 through an input-side by-pass diode group 15 after flowing in the forward direction to the anode side of the thyristor element group 11 through a load-side by-pass diode group 14. A control circuit 17 breaks not only the backward current but also the forward current by using one GTO thyristor element group in such a way that, when the current output of a DC current transformer 16 reaches a self-breaking current value, the circuit 17 breaks the current output by turning off the thyristor element group 11. Therefore, the outside dimension and cost of a bidirectional GTO thyristor breaker can be reduced. |
