Abstract: A switch includes a first contact and a second contact that are placed along an operating shaft and can reciprocate with respect to each other. An end of the second contact opposite to an end thereof on the side of the first contact is housed in a housing space of a housing box. The pressure in the housing space is increased due to an arc generated when the first contact approaches the second contact. The increased in the pressure causes the second contact to move toward the first contact.

Abstract: A switch includes a first contact and a second contact that are placed along an operating shaft and can reciprocate with respect to each other. An end of the second contact opposite to an end thereof on the side of the first contact is housed in a housing space of a housing box. The pressure in the housing space is increased due to an arc generated when the first contact approaches the second contact. The increased in the pressure causes the second contact to move toward the first contact.

Abstract: A DC power generation system in which an arc detector, comprising an arc noise analysis unit which detects an arc which occurs in a DC power generation system based on noise of signal of a voltage-current sensor, a voltage-current variation analysis unit for specifying an arc occurrence point in a case where an arc is detected in the arc noise analysis unit, a voltage-current operation point of output of each string is analyzed based on a signal from a voltage-current sensor and based on variation of voltage-current operation point before and after when an arc is detected and a switch control unit for controlling of opening or closing of a switch based on an arc specified result in a voltage-current variation analysis unit, is provided.

Abstract: A vacuum monitoring device of a vacuum circuit breaker with a line of a vacuum valve led out to the external of a metal tank through a bushing having a shield working as a low-pass filter, includes: a first antenna; a second antenna; a first and a second detection portion measuring intensity of an electromagnetic wave detected by the antennas; and a determination portion determining a vacuum deterioration of the circuit breaker by comparing the intensity of the electromagnetic wave detected by the first and the second detection portions, wherein the first and second detection portion include frequency filters passing a frequency band, of electromagnetic waves resulting from discharges occurring when the vacuum valve deteriorates in vacuum, which is attenuated by the shield.

Abstract: A DC power generation system in which an arc detector, comprising an arc noise analysis unit which detects an arc which occurs in a DC power generation system based on noise of signal of a voltage-current sensor, a voltage-current variation analysis unit for specifying an arc occurrence point in a case where an arc is detected in the arc noise analysis unit, a voltage-current operation point of output of each string is analyzed based on a signal from a voltage-current sensor and based on variation of voltage-current operation point before and after when an arc is detected and a switch control unit for controlling of opening or closing of a switch based on an arc specified result in a voltage-current variation analysis unit, is provided.

Abstract: A vacuum valve includes a fixed side electrode on a fixed side current-carrying shaft and a movable side electrode on a movable side current-carrying shaft. An opening and closing unit is coaxially disposed with the movable side current-carrying shaft, and drives the movable side current-carrying shaft. A chattering suppression structure is coaxially disposed with the fixed side current-carrying shaft on the fixed side of the vacuum valve, and suppresses chattering. The opening and closing unit includes an electromagnetic operating mechanism which drives the movable side current-carrying shaft when energized. A contact pressure spring is coaxially disposed with the electromagnetic operating mechanism, and applies contact pressure between the movable side electrode and the fixed side electrode during contact closing of the vacuum valve.

Abstract: A gas insulated switchgear includes a transformer mounting body; a bushing mounted on the transformer mounting body; and a main circuit conductor. The main circuit conductor includes a first main circuit conductor which is connected to a circuit breaker and is located in the bushing and a second main circuit conductor which is connected to the first main circuit conductor. An insulator extends below the lower end of the transformer mounting body and toward the vicinity of the connection between the first main circuit conductor and the second main circuit conductor, in a region where the first main circuit conductor is located in the transformer mounting body. A ground shield is arranged in the insulator, and extends below the lower end of the transformer mounting body and above a coupling portion between the transformer mounting body and the bushing.

Abstract: An electromagnet mechanism is coaxially disposed with a vacuum interrupter that is disposed in a circuit breaker, and has a movable core and a fixed core facing each other and an electromagnetic coil that makes the movable core and the fixed core separate or come into contact in response to electromagnetic force. A driving rod which is movably disposed in the axial direction of the electromagnet mechanism is coupled to the movable core, and in which one side is coupled to the circuit breaker and the other side passes through an opening side end plate of the electromagnet mechanism to be extended outward from the opening side end plate of the electromagnet mechanism. An indication unit is disposed on the opening side end plate of the electromagnet mechanism, and indicates a state of the circuit breaker in conjunction with the movement of the driving rod.

Abstract: A vacuum monitoring device of a vacuum circuit breaker with a line of a vacuum valve led out to the external of a metal tank through a bushing having a shield working as a low-pass filter, includes: a first antenna; a second antenna; a first and a second detection portion measuring intensity of an electromagnetic wave detected by the antennas; and a determination portion determining a vacuum deterioration of the circuit breaker by comparing the intensity of the electromagnetic wave detected by the first and the second detection portions, wherein the first and second detection portion include frequency filters passing a frequency band, of electromagnetic waves resulting from discharges occurring when the vacuum valve deteriorates in vacuum, which is attenuated by the shield.

Abstract: An electromagnetically operated switching device according to the present invention includes a pair of electromagnetically operated mechanisms for driving a main circuit contact of a switch via a link mechanism symmetrically arranged with respect to an operational center axis, and a length of a spring retaining plate can be regulated in accordance with a change of a link ratio, which is caused by a design change of the main circuit contact.

Abstract: A power switching apparatus includes: a pressure tank having tube-like openings in a shank portion and having an insulating gas sealed therein; a vacuum valve housed in the pressure tank and connected to the pressure tank at one end; bushing conductors penetrating through the openings of the pressure tank and electrically connected to the vacuum valve; and current transformers provided on an outside of the pressure tank and measuring a current flowing through the bushing conductors. Tube-like current transformer installation portions on which to install the current transformers are provided above the openings of the pressure tank and an outside diameter of the openings of the pressure tank is made larger than an outside diameter of the current transformer installation portions.

Abstract: In order to obtain a switchgear which can improve heat dissipation efficiency, in the switchgear which dissipates heat outside an apparatus vessel, the heat being generated from an electrical apparatus placed in the apparatus vessel, the switchgear includes a first heat conductor in which one side is connected to a heat generation portion of the apparatus vessel and the other side is extended toward the apparatus vessel side, a second heat conductor in which one side is disposed near the other side of the first heat conductor and the other side is extended outside the apparatus vessel, and an insulating member between conductors disposed between the other side of the first heat conductor and one side of the second heat conductor.

Abstract: A power switchgear according to the present invention includes a pass-through hole which is formed in a fixed side contact case that is supported by a fixed side insulation supporter to fix and retain the fixed side of a vacuum valve and has a larger inner diameter than an outer diameter of the vacuum valve so that the vacuum valve is capable of horizontally passing through and the fixed side end portion of the vacuum valve is placed by passing through; and a fixed side connection conductor attached to the fixed side contact case and connected to the fixed side end portion of the vacuum valve.

Abstract: In a switch device in which the main circuit contact sections of the switch device, an insulating rod, a driving rod, a contact pressure spring, an open spring, and an electromagnet are all coaxially arranged, a problem exists in that the axial dimension of the switch device becomes large. The present invention has been made to solve the aforementioned problem. An object is to obtain an electromagnet device and a switch device using the electromagnet device, in which shortening the axial dimension of the switch device is achieved by arranging the main circuit contact sections of the switch device, the insulating rod, the driving rod, the contact pressure spring, the open spring, and a part of the electromagnet in the same axial range. Particularly, the open spring and the electromagnet are arranged in the same axial region.

Abstract: An electromagnet mechanism is coaxially disposed with a vacuum interrupter that is disposed in a circuit breaker, and has a movable core and a fixed core facing each other and an electromagnetic coil that makes the movable core and the fixed core separate or come into contact in response to electromagnetic force. A driving rod which is movably disposed in the axial direction of the electromagnet mechanism is coupled to the movable core, and in which one side is coupled to the circuit breaker and the other side passes through an opening side end plate of the electromagnet mechanism to be extended outward from the opening side end plate of the electromagnet mechanism. An indication unit is disposed on the opening side end plate of the electromagnet mechanism, and indicates a state of the circuit breaker in conjunction with the movement of the driving rod.