Hitachi, Ltd.

Kenji Annou

Tokio Yamagiwa

Manabu Takamoto

Masatomo Ohno

Hirohiko Yatsuzuka

Kyuji Yaginuma

Masahiro Shimokawa

Yoshikatsu Enokida

A gas-insulated electrical apparatus includes tanks into each of which insulation gas is sealed, including bus-bars, bus-bar disconnectors connected to the bus-bars, circuit breakers connected to the bus-bar disconnectors, and line disconnectors connected to the circuit breakers, each line disconnector being further connected to a transmission or a transformer; wherein each bus-bar disconnector and each line disconnector include a respective pair of a fixed-contact and a moving-contact, the fixed-contact and the moving-contact being concave and convex, respectively, and each of the moving-contacts in the bus-bar disconnector and the line disconnector is located at the side of a corresponding circuit breaker between the bus-bar disconnector and the line disconnector, a contact-parting speed in the line connector being lower than that in the bus-bar disconnector.

Gas-insulated electrical apparatus

A gas circuit breaker 40 automatically interrupts a fault current such as ground fault current flowing through a conductor 61 of a bus line 60. A high speed grounding switch 10 performs a higher grounding and its releasing operation than the open and close operation of the gas circuit breaker 40 during the open and close operation thereof and guarantees the current interrupting performance and the inter-electrode insulation performance of the gas circuit breaker 40. In association with the electrode arrangement of a disconnecting switch 20, bus lines 60A and 60B are disposed in horizontal direction, a stationary electrode 13 of the high speed grounding switch 10 is provided at the constitutional unit 21 of the disconnecting switch 20 so as to locate on the same straight line as the central axis of the bus line and the movable electrode 11 at the ground side is closed along the same straight line as the central axis of the bus line. The stationary electrode 13 can be provided at a bent corner or a branching portion while locating the stationary electrode 13 and the movable electrode 11 on the same straight line as the center axis of the bus line. Thereby, durability of a gas insulated switch gear device provided with a high speed grounding switch is improved while reducing the entire size and the production cost thereof.

Gas insulated switch gear device

Growing community of inventors

Hitachi, Japan

Kenji Annou