| 摘要 |
PROBLEM TO BE SOLVED: To provide a hybrid type circuit breaker which improves a cutoff function and reliability and in which a two-way semiconductor switch is connected in parallel to a mechanical switch.SOLUTION: In the hybrid type circuit breaker, a two-way semiconductor switch 3 is connected in parallel to a main contact 21 of a mechanical switch 2. When opening the mechanical switch 2, a main circuit current is commutated to the semiconductor switch 3 and OFF control is performed on the semiconductor switch 3, thereby cutting off the main circuit current. A two-way switch that is configured by connecting two reverse blocking IGBT 4-1 and 4-2 in anti-parallel is connected in parallel to the mechanical switch. ON/OFF control is performed by applying an arc voltage of the main contact which is generated when opening the mechanical switch, to gates of the reverse blocking IGBT. Auxiliary contacts 22-1 and 22-2 which perform delayed opening operations later than opening of the main contact 21 are interposed and connected to a gate drive circuit 9, thereby preventing erroneous ignition of the reverse blocking IGBT just after cut-off of the main circuit current commutated from the mechanical switch 2 to the semiconductor switch 3.SELECTED DRAWING: Figure 1 |
