Hitachi, Ltd.

Japan Ae Power Systems Corporation

Hajime Urai

Masanao Terada

Hiroaki Hashimoto

Makoto Hirose

Katsuhiko Shiraishi

Yoichi Oshita

Takahiro Nishimura

Toshiaki Sakuyama

Makoto Koizumi

Ayumu Morita

Yasuaki Aoyama

Toshiaki Rokunohe

Ryoichi Shiobara

Tatsuro Kato

Noriyuki Yaginuma

Yuki Nakai

Yuichiro Yamane

Kinya Nakatsu

Koichiro Adachi

Taichiro Yamashita

Kimihisa Furukawa

Youichi Ohshita

Masataka Sasaki

Junzo Kida

Hiroshi Kamizuma

Takashi Iida

Daisuke Ebisawa

Noriya Nakao

Riichi Nagao

Hideyuki Kotsuji

Naoki Osawa

Provided is a power conversion system that can suppress a fault in a short-circuiting switch that bypasses a fault unit and enhance the reliability and redundancy of the system. The power conversion system is provided with a plurality of power converter units that are formed by using semiconductor switch elements and are connected in series, and comprises: switch elements that are provided to input terminals and/or output terminals of the power converter units and bypass the power converter units; and overvoltage suppressing elements which are connected in parallel with the switch elements and in which conducting states are changed by an application of a prescribed voltage.

Power conversion system

A gas circuit breaker includes a gas suppresser composed of a protruded portion which is formed on a horizontal surface facing an exhaust cylinder of a shaft guide and which forms a gap between itself and the exhaust cylinder and an enlarged portion which is adjacent to the protruded portion and where a gap to the exhaust cylinder is enlarged so that the shaft guide, which operates along an inner circumferential surface of the exhaust cylinder, which is provided to an inner circumferential portion of a movable side main conductor and is provided to outer circumferences of an exhaust shaft and an operation rod, and couples the operation rod with the exhaust shaft, is axially adjacent to a sliding member that slides along the exhaust cylinder with no space to the exhaust cylinder and suppresses discharge of heated and pressurized insulating gas.

Gas circuit breaker

In order to solve the above-described problems, a gas circuit breaker of the present invention has an insulating nozzle disposed so as to cover an inner surface of a coupling member such that an end surface of the coupling member and an end surface of the insulating nozzle form one surface (the end surface of the coupling member is flush with the end surface of the insulating nozzle), in order to suppress contact between a high-temperature and high-pressure gas generated by an arc and the coupling member coupling the insulating nozzle and a driving rod.

To provide a gas circuit breaker designed to achieve further improvement in interruption performance for a small to medium current. The gas circuit breaker according to the present invention includes: an operation mechanism; a heat puffer chamber; a machine puffer chamber; a release valve; a movable main contactand movable arc contact; a stationary main contactand stationary arc contact; a movable-side leading conductor; and a stationary-side leading conductor, and features: a separation cylinderfor radially partitioning the heat puffer chamber; an inner circumferential flow pathformed on an inner circumferential side of the separation cylinder; and a check valvefor opening or closing a communication hole

Realized is a shape of a grooved cam that maximizes break performance by appropriately setting an electrode operation, with a minimum weight increase. A gas circuit breaker includes a drive side electrode and a driven side electrode which are disposed to face each other in a sealed tank, the drive side electrode having a drive side main electrode and a drive side arcing contact, the driven side electrode having a driven side main electrode and a driven side arcing contact, the drive side arcing contact being connected to an operating device, and the driven side arcing contact being connected to a double motion mechanism portion, in which the double motion mechanism portion includes a drive side connection rod that receives driving force from the drive side electrode, a driven side connection rod that is connected to the driven side arcing contact, a lever that is bent to the operating device side around a rotation axis by causing the driven side connection rod to operate in an opposite direction with respect to an operation of the drive side connection rod, and a guide that defines operations of the drive side connection rod and the driven side connection rod.

A bidirectional driving mechanismhas a drive-side linkage rod, a driven-side linkage rod, two leversthat link the drive-side linkage rod with the driven-side linkage rod, and a guidethat regulates the operation of the drive-side linkage rodand the driven-side linkage rod. A moveable pinis passed through a first groove camof the drive-side linkage rod, a second groove camof the guide, and third groove camsof the levers, and by operation of the drive-side rod, the moveable pinmoves within the respective groove cams, causing the leversto rotate, the driven-side linkage rodto be driven in a direction opposite to the drive-side linkage rod, and a driven-side arc electrodeto be driven in a direction opposite to a drive-side arc electrode

A gas circuit breaker includes a sealed tank, a movable side main electrode and a fixed side main electrode in the sealed tank facing each other, a movable side arc electrode and a fixed side arc electrode in the sealed tank facing each other, a cylinder at a circumference of the movable side arc electrode, a piston in the cylinder in a slidable manner and forming a puffer chamber together with the cylinder, an insulation nozzle in the sealed tank, an exhaust pipe at a circumference of the fixed side arc electrode and exhausting heat gas, which is sprayed on an arc generated in the insulation nozzle in the opening electrode operation, to an outside, and a closing plate in the exhaust pipe. One or more vent holes leading the heat gas from an inside of the exhaust pipe to the outside is on a surface of the closing plate.

A method for controlling a power switching apparatus to solve problems including: setting a target time reaching a predetermined position immediately before a target phase by a time calculator during an opening and closing operation of a movable arc contact with respect to a fixed arc contact in a target phase at a predetermined average switching speed; and controlling an electric motor at a speed equal to or less than an average switching speed immediately before the target phase from an operation start time to the target time by a motor controller.

Method for controlling power switching apparatus

The invention is intended to provide a circuit breaker or a circuit breaker operating method enabling a current interruption action to be performed efficiently. A circuit breaker is characterized in that includes a fixed contact and a movable contact that comes in and goes out of contact with the fixed contact; a main circuit conductor that is electrically connected to the fixed contact and the movable contact; an operating mechanism including a mover configured by concatenating permanent magnets or magnetic materials alternately having opposite N and S magnetic polarities along the direction of motion axis of the movable contact and magnetic poles disposed to face the N and S magnetic polarities of the mover and wound with windings; a current detector that detects a current flowing through the main circuit conductor; and a control device that varies the amount of a current to be supplied to the windings of the magnetic poles, depending on a current value detected by the current detector.

Circuit breaker and circuit breaker operating method

To provide a gas circuit breaker having a space-saving and highly reliable double motion mechanism with high design freedom. In a double motion mechanism of the gas circuit breaker, a driven side movable pin is communicated with a lever driven side hole cut in the opposite side with respect to a rotation axis of a lever. A round hole through which a driving side movable pin is inserted and an elongate hole through which the driven side movable pin is inserted are cut in the outside of the lever. A position retaining member to suppress rotation of the driving side movable pin about two axes vertical to a pin axis is provided. The driving side movable pin is moved in respective grooved cams with an operation of the driving side rod, to rotate the lever, drive the driven side connecting rod in an opposite direction to the driving side connecting rod, and drive the driven side arcing contact in an opposite direction to the driving side arcing contact.

Provided is a gas circuit breaker that can reduce control energy smaller than that in previous double motion systems and an excessive force applied to a moveable pin to achieve a highly reliable double motion system. A gas circuit breaker has a double motion mechanism unit including a driving-side connecting rod, a driven-side connecting rod, a lever to connect the rods, and a guide to define the motion of the driving-side and driven-side connecting rods. A moveable pin extends through a first grooved cam of the driving-side conencting rod, a second grooved cam of the guide, and a third grooved cam of the lever. The driving-side connecting rod operates to move the moveable pin inside the grooved cams. Thus, the lever is rotated, the driven-side connecting rod is driven opposite to the driving-side connecting rod, and the driven-side arcing contact is driven opposite to the driving-side arcing contact.

An object is to provide a switchgear having a simple structure. To solve the problem, a switchgear according to the invention is characterized by having a fixed side electrode, a movable side electrodeconfigured to come into contact with or separate from the fixed side electrode, and an operating mechanism configured to allow drive force for movement of the movable side electrodeto be generated, wherein the operating mechanism for operating the movable side electrodeincludes one operating mechanism, and the one operating mechanism allows the movable side electrodeto stop at three or more positions.

Switchgear

A pair of arcing contactsandfacing each other are placed in a tankto perform opening and closing operation, and a puffer cylinderis coaxially provided on the circumference of one arcing contact. A puffer chamberis comprised of the puffer cylinder, a fixed piston, and a hollow rod. An insulating nozzleforming a space communicating with the puffer chamberis provided. An exhaust tubefor exhausting and cooling hot gas discharged from an arc produced in the insulating nozzleis provided on the circumference of the other arcing contact. A structurefor temporarily reducing the flow path area is provided on the inner circumferential surface at short of the end portion of the exhaust tube

A puffer type gas circuit breaker has a piston, which is connected with a center shaft via a link mechanism. At an initial stage of an interruption operation, the link mechanism drives a puffer cylinder and the piston both in an interruption direction while maintaining an almost constant distance therebetween. Even when a pressure rise occurs in a compression chamber by the heat of an arc generated in accordance with opening between a fixed arc contact and a movable arc contact, the pressure rise does not become an operation counterforce to an operator. At a final stage of the interruption operation where the fixed arc contact is removed from a throat of an insulating nozzle, the link mechanism drives the piston in an almost stopped status.

Growing community of inventors

Tokyo, Japan

Hajime Urai