US20050103514A1 - Vacuum switchgear - Google Patents
Vacuum switchgear Download PDFInfo
- Publication number
- US20050103514A1 US20050103514A1 US10/914,290 US91429004A US2005103514A1 US 20050103514 A1 US20050103514 A1 US 20050103514A1 US 91429004 A US91429004 A US 91429004A US 2005103514 A1 US2005103514 A1 US 2005103514A1
- Authority
- US
- United States
- Prior art keywords
- shield
- vacuum container
- vacuum
- side conductor
- conductor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/662—Housings or protective screens
- H01H33/66261—Specific screen details, e.g. mounting, materials, multiple screens or specific electrical field considerations
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H31/00—Air-break switches for high tension without arc-extinguishing or arc-preventing means
- H01H31/003—Earthing switches
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/666—Operating arrangements
- H01H33/6661—Combination with other type of switch, e.g. for load break switches
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H1/00—Contacts
- H01H1/58—Electric connections to or between contacts; Terminals
- H01H1/5822—Flexible connections between movable contact and terminal
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/662—Housings or protective screens
- H01H33/66261—Specific screen details, e.g. mounting, materials, multiple screens or specific electrical field considerations
- H01H2033/66284—Details relating to the electrical field properties of screens in vacuum switches
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/666—Operating arrangements
- H01H2033/6668—Operating arrangements with a plurality of interruptible circuit paths in single vacuum chamber
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/02—Details
- H01H33/022—Details particular to three-phase circuit breakers
Definitions
- the present invention relates to a vacuum switchgear and more particularly to a vacuum switchgear, in which a switch having a stationary electrode and a movable electrode is enclosed in a vacuum container that requires grounding.
- a vacuum container accommodates a main circuit switching unit for connecting and disconnecting a main circuit conductor to and from a load side conductor or a bus side conductor and a main circuit/earth selecting unit for connecting the main circuit conductor to and from the bus side conductor or the load side conductor and an earthing conductor and in which the vacuum container is formed of a grounded metal or an insulating material with a grounded layer on its surface.
- This vacuum container accommodates the main circuit conductor and a part of each of the bus side conductor, the earthing conductor and the load side conductor.
- the vacuum container also has an air terminal unit that respectively connects in air those portions of the bus side conductor, the earthing conductor and the load side conductor projecting from the vacuum container to the bus side, the earth side and the load side.
- an air terminal unit that respectively connects in air those portions of the bus side conductor, the earthing conductor and the load side conductor projecting from the vacuum container to the bus side, the earth side and the load side.
- drive mechanisms are installed to operate the main circuit switching unit and the main circuit/earthing selecting unit. This construction is seen in JP-A-2001-346306, page 4-6 and FIG. 4, for instance.
- the interruption and insulation performance can be enhanced, allowing the devices to be made compact.
- the vacuum container with the integrated functions serves as one component. There is therefore an advantage that the number of components can be reduced and the reliability improved. Further, by earthing the vacuum container an inspection can be performed online.
- particulate foreign matters of a few micron meters may be formed by the open-close operation of the switching unit or during the manufacturing process. If these particulates reach a high electric field area in vacuum, a dielectric breakdown may occur even at service voltage. More specifically, an intermediate shield is provided around the main circuit switching unit among the switching units in the vacuum switchgear to shield an arc produced during the open-close operation, and a dielectric breakdown is prevented from being triggered by an arc.
- the other conductors than the main circuit switching unit also provide electric field concentrated regions but are not shielded. If foreign particles enter the electric field concentrated regions, therefore, they can conduct electricity between the conductors in the field concentrated regions and the grounded vacuum container, resulting in a dielectric breakdown.
- This dielectric breakdown may occur even when the dielectric strength of devices is verified in a withstand voltage test to be several times the service voltage.
- a circuit breaker may be tripped, resulting in a power system failure.
- the field intensity of the electric field concentrated regions has to be reduced, and therefore the sizes of the devices require increasing to lengthen the insulation distances.
- An object of this invention is to prevent a dielectric breakdown due to foreign particulates and improve the insulation reliability of devices.
- the present invention is contrived that a switching unit having a stationary electrode and a movable electrode is accommodated in a vacuum container required to be earthed, the stationary electrode and the movable electrode are connected to a bus side conductor and a load side conductor or vice versa through wiring conductors in the container, a shield is arranged inside the vacuum container to shield a part or all of an area where particulate foreign matters are produced by open-close operation of the switching unit, and the shield is secured to the vacuum container in a insulated condition therefrom.
- FIG. 1 is a vertical sectional view of a vacuum switchgear showing an embodiment of the invention.
- FIG. 2 is a vertical sectional view of a vacuum switchgear showing the second embodiment of the invention.
- FIG. 3 is a plan view of the vacuum switchgear shown in FIG. 2 .
- FIG. 1 is a vertical sectional view of a vacuum switchgear showing the embodiment of the invention.
- the vacuum switchgear is represented by one phase of one unit in a power receiving and distribution board comprised of a plurality of units.
- a main circuit switching unit 10 an isolator 20 , flexible conductors 63 , 64 , an earthing device 30 and so on are accommodated in vacuum containers 1 , 2 that need to be grounded, i.e., in the vacuum containers which are grounded and formed of a metal (stainless steel).
- a conductor 61 and a main circuit conductor 62 are arranged to extend inside and outside the vacuum containers 1 , 2 .
- the main circuit switching unit 10 has a movable electrode 11 and a stationary electrode 12 and is installed in the vacuum container 1 , separated by a spacer 15 from the isolator 20 .
- An intermediate shield 13 is arranged around the movable electrode 11 and the stationary electrode 12 to shield an arc generated when the circuit is opened and closed.
- the stationary electrode 12 is inserted through a through-hole in a central part of the spacer 15 to be supported by the spacer 15 and is connected to a stationary electrode 22 of the isolator 20 .
- Around the movable electrode 11 is arranged an insulator 14 to prevent charged particulates produced during opening and closing of the movable electrode 11 and the stationary electrode 12 from diffusing outward.
- the insulator 14 is connected to an end of the intermediate shield 13 .
- the movable electrode 11 is connected to the conductor 61 through the flexible conductor 63 which serves as a wiring conductor in the container.
- the conductor 61 is inserted into a through-hole in a ceramic connecting portion 81 arranged in and out of the vacuum container 1 .
- the conductor 61 is integrally formed at its end with a disk-shaped portion 61 a for reducing an electric field concentration.
- This conductor 61 serves as a bus side conductor when it is connected to a bus disposed outside the vacuum container 1 and as a load side conductor when it is connected to a power line connected to a load.
- the movable electrode 11 is connected through an insulating rod 17 to a bellows 18 and an operation rod 19 .
- the movable electrode 11 is thus operated for engagement with or disengagement from the stationary electrode 12 by switching operation of the operation rod 19 coupled to an outside driving mechanism. That is, the main circuit switching unit 10 is adapted to connect or disconnect the conductor 61 and the main circuit conductor 62 by open and close operation of the movable electrode 11 and the stationary electrode 12 .
- the movable electrode 11 and the stationary electrode 12 are formed by mixing a slight amount of such substances as chromium and cobalt to copper to improve an arc resistance and thereby have an excellent current interrupting capability.
- the flexible conductor 63 is made by laminating a plurality of thin copper plates.
- the isolator 20 is received in the vacuum container 2 as an auxiliary switch with a stationary electrode 22 and a movable electrode 21 and is so constructed as to connect or disconnect the main circuit conductor 62 and the main circuit switching unit 10 .
- the movable electrode 21 is connected to the main circuit conductor 62 through the flexible conductor 64 serving as a wiring conductor in the container.
- the main circuit conductor 62 is inserted into a through-hole in a ceramic connecting portion 82 arranged in and out of the vacuum container 2 and is integrally formed at its almost central part with a disk-shaped portion 62 a for reducing an electric field intensity.
- the main circuit conductor 62 serves as a bus side conductor when it is connected to the bus situated outside the vacuum container 2 and as a load side conductor when it is connected to the power line connected with the load.
- the movable electrode 21 is connected through an insulating rod 27 to a bellows 28 and an operation rod 29 .
- the isolator 20 is opened or closed as the operation rod 29 is operated by an outside driving mechanism.
- An end of the flexible conductor 64 and an end of the main circuit conductor 62 are each connected to an earthing device 30 having a bellows 38 and an earthing conductor 39 .
- the earthing conductor 39 is opened and closed by an outside driving mechanism.
- the main circuit conductor 62 is earthed through the earthing conductor 39 .
- the flexible conductor 64 is made by laminating a plurality of thin copper plates.
- Ceramic materials used for the connecting portions 81 , 82 include alumina, silica, magnesium oxide, titanium oxide, mica, boron nitride, aluminum fluoride and the like.
- shields 101 , 103 , 105 , 107 and 109 that shield a part or all of areas where particulate foreign matters are produced during the operation of the main circuit switching unit 10 and the isolator 20 , such as electric field concentrated regions, are arranged inside the vacuum containers 1 , 2 .
- the respective shields 101 , 103 , 105 , 107 and 109 are insulated from the vacuum containers 1 , 2 . That is, the shields 101 , 103 , 105 , 107 and 109 are secured to the vacuum containers 1 , 2 through spacers 100 , 102 , 104 , 106 , 108 made of insulating material.
- the shields 101 , 107 are formed cylindrical and the shields 103 , 105 , 109 are formed like a plate.
- the shields 101 , 103 , 105 , 107 , 109 have their ends bent inward to reduce electric field concentration.
- the shield 101 is constructed to shield particulate foreign matters produced by the conductor 61 , the disk-shaped portion 61 a and the flexible conductor 63 .
- the shield 107 is constructed to shield particulate foreign matters coming from the main circuit conductor 62 and the disk-shaped portion 62 a .
- the shield 103 is designed to shield particulate foreign matters coming from a connecting portion between the flexible conductor 63 and the movable electrode 11 .
- the shield 105 is designed to shield particulate foreign matters coming from the isolator 20 .
- the shield 109 is designed to shield particulate foreign matters coming from the flexible conductor 64 and the main circuit conductor 62 .
- the shields 101 , 103 , 105 , 107 , 109 are insulated from the vacuum containers 1 , 2 , at the moment when the shields 101 , 103 , 105 , 107 , 109 and the electric field concentrated regions are brought to the same potential, an electric field between the conductors of the field concentrated regions and the shields 101 , 103 , 105 , 107 , 109 disappears and charged particles produced by the dielectric breakdown phenomenon are no longer accelerated by the field, making it impossible for the dielectric breakdown phenomenon to persist. Then, once the dielectric breakdown phenomenon disappears, the particulate foreign matters which triggered the dielectric breakdown phenomenon disappear with it.
- the dielectric strength of the devices when there are no particulate foreign matter is more than several times the service voltage, the dielectric strength is instantly restored, protecting the devices against damages.
- the dielectric strength between the shields 101 , 103 , 105 , 107 , 109 and the vacuum containers 1 , 2 strong enough to withstand the service voltage, it is also possible to avoid a ground fault and prevent a dielectric breakdown phenomenon from causing a possible failure of the power system.
- each isolator 20 is received in the vacuum container 1 in addition to the main circuit switching unit 10 , with each isolator 20 electrically connected to the main circuit switching unit 10 .
- the main circuit switching unit 10 and the isolators 20 are each provided with an earthing device 30 so that they can be earthed independently of each other.
- the movable electrode 21 of each isolator 20 is connected through the flexible conductor 64 to the conductor 65 , which in turn is connected to the conductor 66 .
- the movable electrode 11 of the main circuit switching unit 10 is connected through the flexible conductor 63 to the conductor 65 .
- the conductor 65 of the main circuit switching unit 10 is connected through a conductor 67 to the conductor 65 of the adjoining isolator 20 .
- shields 111 , 113 , 115 , 117 , 121 made of a metal plate are arranged inside the vacuum container 1 to enclose the main circuit switching unit 10 , the isolators 20 and the earthing devices 30 by taking areas surrounding the main circuit switching unit 10 and the isolators 20 as particulate foreign matter generation areas.
- the respective shields 111 , 113 , 115 , 117 are secured to the vacuum container 1 through spacers 110 , 112 , 114 , 118 as insulating members, and the insulating plates 121 are secured to the vacuum container 1 through insulating rods 17 , 27 .
- the shields 111 , 113 , 115 , 117 , 121 each shaped like a plate have their opposite ends bent inward in a large radius to allow reduction of electric field concentration. Covering the ends of the shields with an insulating material can further enhance the dielectric strength. Covering of the ends with the insulating material may be carried out by covering them with a ceramic sheet or by forming a diamond-shaped carbon thin film.
- the shields 111 , 113 , 115 , 117 , 121 insulated from the vacuum container 1 are arranged inside the vacuum container 1 , if a dielectric breakdown phenomenon due to particulate foreign matters occurs at electric field concentrated regions on the main circuit switching unit 10 , the isolators 20 and the earthing devices 30 , it is possible to prevent the dielectric breakdown phenomenon from damaging the devices and to avoid a ground fault. This in turn prevents the dielectric breakdown phenomenon from causing a possible failure of the power system.
- the connecting portions 81 , 82 , the conductor 61 and the main circuit conductor 62 are arranged in the same direction, and the operation rods 19 , 29 , 39 are also arranged in the same direction as those of the conductor 61 and the main circuit conductor 62 .
- the switchgear therefore can be constructed in a simple configuration with its sides almost planar, and the shields 111 , 113 , 115 and 117 can also be in simple shapes. This makes the installation easy.
- the disk-shaped shields 121 are arranged around the insulating rods 17 , 27 . Therefore, if a dielectric breakdown phenomenon occurs in an upper space of the vacuum container 1 due to particulate foreign matters coming from an upper side of the main circuit switching unit 10 and the isolators 20 , this dielectric breakdown phenomenon can be instantly eliminated by the shields 121 .
- shields below the main circuit switching unit 10 and the isolators 20 through insulating spacers can prevent particulate foreign matters lying on the bottom of the container from floating up.
- the shields have been described as being formed of metal plates, they may be formed of an insulating material such as ceramics. If the shields are made of ceramics, when a dielectric breakdown phenomenon occurs, the surfaces of the shields become the same electrical potential with that of the conductors.
- the ceramics material may be alumina, silica, magnesium oxide, titanium oxide, mica, boron nitride and aluminum fluoride.
- the DC voltage can be prevented from acting on the shields by providing the surface of the insulating material with a highly resistive conductive layer that does not affect the insulation against an AC voltage and by dissipating charges accumulated on the shields. This can reduce the insulation distances and allows the devices to be made compact.
- a highly resistive conductive layer may be formed over the surfaces of the shields made of a metal plate to connect the metal plate and the vacuum container.
- the resistance of the conductive layer has to be more than 10 10 ⁇ .
- the shields have been described as each being arranged between the conductor and the vacuum container, a plurality of shields may be stacked together and installed to reduce a voltage applied to each of the shields, thus enhancing the insulation reliability.
- a spacer as an insulating material is inserted between the shields.
- the same number of switching units, each having a stationary electrode and a movable electrode, as that of phases, e.g. three units for three phases, may be installed.
- the stationary electrode and the movable electrode of each phase are connected to a bus side conductor and a load side conductor of the corresponding phase or vice versa through wiring conductors of the associated phase in the containers, e.g. flexible conductors.
- Shields are installed inside, and insulated from, the vacuum containers to shield a part or all of areas where particulate foreign matters are produced by the open-close operation of the switching unit of each phase.
Landscapes
- Gas-Insulated Switchgears (AREA)
- High-Tension Arc-Extinguishing Switches Without Spraying Means (AREA)
Abstract
Description
- The present invention relates to a vacuum switchgear and more particularly to a vacuum switchgear, in which a switch having a stationary electrode and a movable electrode is enclosed in a vacuum container that requires grounding.
- As a conventional vacuum switchgear, for example, there is a construction, in which a vacuum container accommodates a main circuit switching unit for connecting and disconnecting a main circuit conductor to and from a load side conductor or a bus side conductor and a main circuit/earth selecting unit for connecting the main circuit conductor to and from the bus side conductor or the load side conductor and an earthing conductor and in which the vacuum container is formed of a grounded metal or an insulating material with a grounded layer on its surface. This vacuum container accommodates the main circuit conductor and a part of each of the bus side conductor, the earthing conductor and the load side conductor. Further, the vacuum container also has an air terminal unit that respectively connects in air those portions of the bus side conductor, the earthing conductor and the load side conductor projecting from the vacuum container to the bus side, the earth side and the load side. On the outside of the vacuum container, drive mechanisms are installed to operate the main circuit switching unit and the main circuit/earthing selecting unit. This construction is seen in JP-A-2001-346306, page 4-6 and FIG. 4, for instance.
- By integrating an interrupting function, a disconnecting function and an earthing function in the single earthed vacuum container, the interruption and insulation performance can be enhanced, allowing the devices to be made compact. During assembly, the vacuum container with the integrated functions serves as one component. There is therefore an advantage that the number of components can be reduced and the reliability improved. Further, by earthing the vacuum container an inspection can be performed online.
- In the conventional vacuum switchgear, particulate foreign matters of a few micron meters may be formed by the open-close operation of the switching unit or during the manufacturing process. If these particulates reach a high electric field area in vacuum, a dielectric breakdown may occur even at service voltage. More specifically, an intermediate shield is provided around the main circuit switching unit among the switching units in the vacuum switchgear to shield an arc produced during the open-close operation, and a dielectric breakdown is prevented from being triggered by an arc. However, the other conductors than the main circuit switching unit also provide electric field concentrated regions but are not shielded. If foreign particles enter the electric field concentrated regions, therefore, they can conduct electricity between the conductors in the field concentrated regions and the grounded vacuum container, resulting in a dielectric breakdown. This dielectric breakdown may occur even when the dielectric strength of devices is verified in a withstand voltage test to be several times the service voltage. When this dielectric breakdown is detected as a ground fault by a protective control system in the power system, a circuit breaker may be tripped, resulting in a power system failure. To prevent the dielectric breakdown the field intensity of the electric field concentrated regions has to be reduced, and therefore the sizes of the devices require increasing to lengthen the insulation distances.
- An object of this invention is to prevent a dielectric breakdown due to foreign particulates and improve the insulation reliability of devices.
- To achieve the above object, the present invention is contrived that a switching unit having a stationary electrode and a movable electrode is accommodated in a vacuum container required to be earthed, the stationary electrode and the movable electrode are connected to a bus side conductor and a load side conductor or vice versa through wiring conductors in the container, a shield is arranged inside the vacuum container to shield a part or all of an area where particulate foreign matters are produced by open-close operation of the switching unit, and the shield is secured to the vacuum container in a insulated condition therefrom.
- In this construction, for instance, when particulate foreign matters reach a high electric field area near the conductors, a dielectric breakdown phenomenon occurs only between the conductors and the shield but not between the shield and the vacuum container. Thus, this dielectric breakdown does not result in a ground fault, nor does it lead to a power system failure. More specifically, in the event that a dielectric breakdown phenomenon is caused by particulate foreign matters, the shield and the conductors are instantly brought to the same potential. However, since the shield is insulated from the vacuum container, an electric field between the conductors and the shield disappears, no longer accelerating charged particles generated by the dielectric breakdown. The dielectric breakdown therefore can no longer persist, and the dielectric strength can recover instantly, preventing damages to the devices. This in turn can prevent a ground fault and also prevent the dielectric breakdown phenomenon from providing a cause for a possible power system failure.
- According to the invention it is possible to prevent damages to the devices and a ground fault and to prevent a cause for a possible power system failure.
- Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings.
-
FIG. 1 is a vertical sectional view of a vacuum switchgear showing an embodiment of the invention. -
FIG. 2 is a vertical sectional view of a vacuum switchgear showing the second embodiment of the invention. -
FIG. 3 is a plan view of the vacuum switchgear shown inFIG. 2 . - An embodiment of the invention will be now described with reference to the accompanying drawings.
FIG. 1 is a vertical sectional view of a vacuum switchgear showing the embodiment of the invention. InFIG. 1 , the vacuum switchgear is represented by one phase of one unit in a power receiving and distribution board comprised of a plurality of units. In this embodiment, a maincircuit switching unit 10, anisolator 20,flexible conductors earthing device 30 and so on are accommodated invacuum containers conductor 61 and amain circuit conductor 62 are arranged to extend inside and outside thevacuum containers - The main
circuit switching unit 10 has amovable electrode 11 and astationary electrode 12 and is installed in thevacuum container 1, separated by aspacer 15 from theisolator 20. Anintermediate shield 13 is arranged around themovable electrode 11 and thestationary electrode 12 to shield an arc generated when the circuit is opened and closed. Thestationary electrode 12 is inserted through a through-hole in a central part of thespacer 15 to be supported by thespacer 15 and is connected to astationary electrode 22 of theisolator 20. Around themovable electrode 11 is arranged aninsulator 14 to prevent charged particulates produced during opening and closing of themovable electrode 11 and thestationary electrode 12 from diffusing outward. Theinsulator 14 is connected to an end of theintermediate shield 13. Themovable electrode 11 is connected to theconductor 61 through theflexible conductor 63 which serves as a wiring conductor in the container. Theconductor 61 is inserted into a through-hole in a ceramic connectingportion 81 arranged in and out of thevacuum container 1. Theconductor 61 is integrally formed at its end with a disk-shaped portion 61a for reducing an electric field concentration. Thisconductor 61 serves as a bus side conductor when it is connected to a bus disposed outside thevacuum container 1 and as a load side conductor when it is connected to a power line connected to a load. - The
movable electrode 11 is connected through aninsulating rod 17 to abellows 18 and anoperation rod 19. Themovable electrode 11 is thus operated for engagement with or disengagement from thestationary electrode 12 by switching operation of theoperation rod 19 coupled to an outside driving mechanism. That is, the maincircuit switching unit 10 is adapted to connect or disconnect theconductor 61 and themain circuit conductor 62 by open and close operation of themovable electrode 11 and thestationary electrode 12. Themovable electrode 11 and thestationary electrode 12 are formed by mixing a slight amount of such substances as chromium and cobalt to copper to improve an arc resistance and thereby have an excellent current interrupting capability. Theflexible conductor 63 is made by laminating a plurality of thin copper plates. - The
isolator 20 is received in thevacuum container 2 as an auxiliary switch with astationary electrode 22 and amovable electrode 21 and is so constructed as to connect or disconnect themain circuit conductor 62 and the maincircuit switching unit 10. Themovable electrode 21 is connected to themain circuit conductor 62 through theflexible conductor 64 serving as a wiring conductor in the container. Themain circuit conductor 62 is inserted into a through-hole in a ceramic connectingportion 82 arranged in and out of thevacuum container 2 and is integrally formed at its almost central part with a disk-shaped portion 62 a for reducing an electric field intensity. Themain circuit conductor 62 serves as a bus side conductor when it is connected to the bus situated outside thevacuum container 2 and as a load side conductor when it is connected to the power line connected with the load. Themovable electrode 21 is connected through aninsulating rod 27 to abellows 28 and anoperation rod 29. Theisolator 20 is opened or closed as theoperation rod 29 is operated by an outside driving mechanism. An end of theflexible conductor 64 and an end of themain circuit conductor 62 are each connected to anearthing device 30 having abellows 38 and anearthing conductor 39. Theearthing conductor 39 is opened and closed by an outside driving mechanism. Themain circuit conductor 62 is earthed through theearthing conductor 39. Theflexible conductor 64 is made by laminating a plurality of thin copper plates. - Ceramic materials used for the connecting
portions - In the vacuum switchgear of the above construction, when a high electric field is applied, the electric field tends to concentrates on corners, bent portions, protruding portions and ends of the disk-shaped
portion 61 a of theconductor 61, the disk-shapedportion 62 a of themain circuit conductor 62, theflexible conductors circuit switching unit 10 and theisolator 20. Particulate foreign matters of a few micron meters may be produced in the manufacturing process or during open-close operations. These particulate foreign matters, if left as are, may lead to a dielectric breakdown. Equipment is basically designed and manufactured in a manner that prevents formation of such particulate foreign matters. However, if the particulate foreign matters formed nevertheless can be made harmless, the manufacturing process can be simplified and the equipment reliability improved. - In this embodiment, therefore, shields 101, 103, 105, 107 and 109 that shield a part or all of areas where particulate foreign matters are produced during the operation of the main
circuit switching unit 10 and theisolator 20, such as electric field concentrated regions, are arranged inside thevacuum containers respective shields vacuum containers shields vacuum containers spacers shields shields shields shield 101 is constructed to shield particulate foreign matters produced by theconductor 61, the disk-shapedportion 61 a and theflexible conductor 63. Theshield 107 is constructed to shield particulate foreign matters coming from themain circuit conductor 62 and the disk-shapedportion 62 a. Theshield 103 is designed to shield particulate foreign matters coming from a connecting portion between theflexible conductor 63 and themovable electrode 11. Theshield 105 is designed to shield particulate foreign matters coming from theisolator 20. Theshield 109 is designed to shield particulate foreign matters coming from theflexible conductor 64 and themain circuit conductor 62. - With the above construction, if a dielectric breakdown phenomenon occurs in the electric field concentrated regions due to the formation of particulate foreign matters, in that instant, an electricity flows between the field concentrated regions and the
shields shields vacuum containers shields shields shields vacuum containers - Next, a second embodiment of the invention will be described with reference to
FIG. 2 andFIG. 3 . In this embodiment twoisolators 20 are received in thevacuum container 1 in addition to the maincircuit switching unit 10, with each isolator 20 electrically connected to the maincircuit switching unit 10. The maincircuit switching unit 10 and theisolators 20 are each provided with an earthingdevice 30 so that they can be earthed independently of each other. Themovable electrode 21 of each isolator 20 is connected through theflexible conductor 64 to theconductor 65, which in turn is connected to theconductor 66. Themovable electrode 11 of the maincircuit switching unit 10 is connected through theflexible conductor 63 to theconductor 65. Theconductor 65 of the maincircuit switching unit 10 is connected through aconductor 67 to theconductor 65 of the adjoiningisolator 20. - In this embodiment, shields 111, 113, 115, 117, 121 made of a metal plate are arranged inside the
vacuum container 1 to enclose the maincircuit switching unit 10, theisolators 20 and the earthingdevices 30 by taking areas surrounding the maincircuit switching unit 10 and theisolators 20 as particulate foreign matter generation areas. Therespective shields vacuum container 1 throughspacers plates 121 are secured to thevacuum container 1 through insulatingrods shields - In this embodiment, since the
shields vacuum container 1 are arranged inside thevacuum container 1, if a dielectric breakdown phenomenon due to particulate foreign matters occurs at electric field concentrated regions on the maincircuit switching unit 10, theisolators 20 and the earthingdevices 30, it is possible to prevent the dielectric breakdown phenomenon from damaging the devices and to avoid a ground fault. This in turn prevents the dielectric breakdown phenomenon from causing a possible failure of the power system. - Further, in this embodiment, the connecting
portions conductor 61 and themain circuit conductor 62 are arranged in the same direction, and theoperation rods conductor 61 and themain circuit conductor 62. The switchgear therefore can be constructed in a simple configuration with its sides almost planar, and theshields - Further, the disk-shaped
shields 121 are arranged around the insulatingrods vacuum container 1 due to particulate foreign matters coming from an upper side of the maincircuit switching unit 10 and theisolators 20, this dielectric breakdown phenomenon can be instantly eliminated by theshields 121. - Further, also installing shields below the main
circuit switching unit 10 and theisolators 20 through insulating spacers can prevent particulate foreign matters lying on the bottom of the container from floating up. - Although in each of the above embodiments, the shields have been described as being formed of metal plates, they may be formed of an insulating material such as ceramics. If the shields are made of ceramics, when a dielectric breakdown phenomenon occurs, the surfaces of the shields become the same electrical potential with that of the conductors. The ceramics material may be alumina, silica, magnesium oxide, titanium oxide, mica, boron nitride and aluminum fluoride.
- Following a dielectric breakdown phenomenon occurring between the shields and the conductors, there is a case where a peak potential of AC service voltage remains on the shields. In this case, a dielectric strength for withstanding the DC voltage is required. If insulation distances corresponding to the required dielectric strength are provided, there is no problem. Alternatively, the DC voltage can be prevented from acting on the shields by providing the surface of the insulating material with a highly resistive conductive layer that does not affect the insulation against an AC voltage and by dissipating charges accumulated on the shields. This can reduce the insulation distances and allows the devices to be made compact. For example, a highly resistive conductive layer may be formed over the surfaces of the shields made of a metal plate to connect the metal plate and the vacuum container. Here, the resistance of the conductive layer has to be more than 1010 Ω.
- Although the shields have been described as each being arranged between the conductor and the vacuum container, a plurality of shields may be stacked together and installed to reduce a voltage applied to each of the shields, thus enhancing the insulation reliability. In this case, a spacer as an insulating material is inserted between the shields.
- In installing the switching units such as the main
circuit switching unit 10 and theisolator 20 in thevacuum containers - It should be further understood that although the foregoing description has been made on the embodiments of the invention, the invention is not limited solely to the specific forms and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims.
Claims (12)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/079,079 US7244903B2 (en) | 2003-11-17 | 2005-03-15 | Vacuum switchgear |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2003386385A JP4403782B2 (en) | 2003-11-17 | 2003-11-17 | Vacuum switchgear |
JP2003-386385 | 2003-11-17 |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/079,079 Continuation US7244903B2 (en) | 2003-11-17 | 2005-03-15 | Vacuum switchgear |
Publications (2)
Publication Number | Publication Date |
---|---|
US6884940B1 US6884940B1 (en) | 2005-04-26 |
US20050103514A1 true US20050103514A1 (en) | 2005-05-19 |
Family
ID=34431518
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/914,290 Expired - Fee Related US6884940B1 (en) | 2003-11-17 | 2004-08-10 | Vacuum switchgear |
US11/079,079 Expired - Fee Related US7244903B2 (en) | 2003-11-17 | 2005-03-15 | Vacuum switchgear |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/079,079 Expired - Fee Related US7244903B2 (en) | 2003-11-17 | 2005-03-15 | Vacuum switchgear |
Country Status (5)
Country | Link |
---|---|
US (2) | US6884940B1 (en) |
JP (1) | JP4403782B2 (en) |
KR (1) | KR20050047460A (en) |
CN (1) | CN1310266C (en) |
TW (1) | TWI240292B (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008090175A1 (en) * | 2007-01-24 | 2008-07-31 | Siemens Aktiengesellschaft | Electric direct current network for water vessels and for offshore units having increased shut-off security |
EP2249363A1 (en) * | 2009-05-07 | 2010-11-10 | ABB Research Ltd. | Arrangement, substation, operating method and use of a grounding switch for protecting an electrical circuit against short-line faults |
DE102014213944A1 (en) * | 2014-07-17 | 2016-01-21 | Siemens Aktiengesellschaft | Electrical switching device for medium and / or high voltage applications |
DE102016217625A1 (en) * | 2016-03-30 | 2017-10-05 | Siemens Aktiengesellschaft | High voltage component and device with a high voltage component |
US11527873B2 (en) | 2017-12-19 | 2022-12-13 | Abb Schweiz Ag | Inner compartment design for medium voltage switchgears |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI263236B (en) * | 2003-05-19 | 2006-10-01 | Hitachi Ltd | Vacuum switchgear |
TWI251847B (en) * | 2003-12-26 | 2006-03-21 | Hitachi Ltd | Vacuum switchgear system and kit for system |
JP4423598B2 (en) * | 2004-08-17 | 2010-03-03 | 株式会社日立製作所 | Single phase module of vacuum switchgear and vacuum switchgear |
JP4748024B2 (en) * | 2006-10-16 | 2011-08-17 | パナソニック電工株式会社 | 2-wire switch device |
FR2920061A1 (en) * | 2007-08-17 | 2009-02-20 | Patrick Camurati | METHOD AND DEVICE FOR TRANSPORTING, DISTRIBUTING AND MANAGING ELECTRICAL ENERGY BY LONGITUDINAL COUPLING IN A CLOSE FIELD BETWEEN ELECTRIC DIPOLES |
JP5425591B2 (en) * | 2008-12-02 | 2014-02-26 | 三菱電機株式会社 | Gas insulated switchgear |
JP5208013B2 (en) * | 2009-02-17 | 2013-06-12 | 三菱電機株式会社 | Fluid insulated electrical equipment |
EP2312606B1 (en) * | 2009-10-14 | 2013-02-27 | ABB Technology AG | Circuit-breaker with a common housing |
US9177742B2 (en) | 2011-10-18 | 2015-11-03 | G & W Electric Company | Modular solid dielectric switchgear |
JP5183794B2 (en) * | 2011-11-24 | 2013-04-17 | 株式会社日立製作所 | Switchgear |
JP5978124B2 (en) * | 2012-12-26 | 2016-08-24 | 株式会社日立製作所 | Switchgear |
JP6136597B2 (en) * | 2013-06-06 | 2017-05-31 | 株式会社明電舎 | Sealed relay |
DE102019209871A1 (en) * | 2019-07-04 | 2021-01-07 | Siemens Aktiengesellschaft | Switching device |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6144005A (en) * | 1997-07-23 | 2000-11-07 | Hitachi, Ltd. | Vacuum switch and a vacuum switchgear using the same |
US6153846A (en) * | 1998-03-19 | 2000-11-28 | Hitachi, Ltd. | Vacuum insulated switching apparatus |
US6426627B2 (en) * | 1999-12-16 | 2002-07-30 | Hitachi, Ltd. | Vacuum switch including vacuum-measurement devices, switchgear using the vacuum switch, and operation method thereof |
US6498314B2 (en) * | 2000-04-19 | 2002-12-24 | Hitachi, Ltd. | Vacuum switch and vacuum switchgear using the same |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1255223A (en) * | 1969-03-11 | 1971-12-01 | Mitsubishi Electric Corp | Vacuum circuit interrupter |
US6335502B1 (en) * | 1998-10-02 | 2002-01-01 | Hitachi, Ltd. | Vacuum switch and vacuum switch gear using the vacuum switch |
JP4470228B2 (en) * | 1998-11-06 | 2010-06-02 | 三菱電機株式会社 | Vacuum switch |
JP2001346306A (en) * | 2000-05-31 | 2001-12-14 | Meidensha Corp | Switchgear |
JP4135870B2 (en) * | 2002-04-16 | 2008-08-20 | 株式会社日立製作所 | Vacuum switch |
JP3752598B2 (en) * | 2002-07-12 | 2006-03-08 | 株式会社日立製作所 | Vacuum switchgear |
TWI263236B (en) * | 2003-05-19 | 2006-10-01 | Hitachi Ltd | Vacuum switchgear |
-
2003
- 2003-11-17 JP JP2003386385A patent/JP4403782B2/en not_active Expired - Fee Related
-
2004
- 2004-06-18 TW TW093117699A patent/TWI240292B/en not_active IP Right Cessation
- 2004-07-08 CN CNB2004100624656A patent/CN1310266C/en not_active Expired - Fee Related
- 2004-08-10 US US10/914,290 patent/US6884940B1/en not_active Expired - Fee Related
- 2004-08-19 KR KR1020040065290A patent/KR20050047460A/en not_active Application Discontinuation
-
2005
- 2005-03-15 US US11/079,079 patent/US7244903B2/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6144005A (en) * | 1997-07-23 | 2000-11-07 | Hitachi, Ltd. | Vacuum switch and a vacuum switchgear using the same |
US6153846A (en) * | 1998-03-19 | 2000-11-28 | Hitachi, Ltd. | Vacuum insulated switching apparatus |
US6426627B2 (en) * | 1999-12-16 | 2002-07-30 | Hitachi, Ltd. | Vacuum switch including vacuum-measurement devices, switchgear using the vacuum switch, and operation method thereof |
US6498314B2 (en) * | 2000-04-19 | 2002-12-24 | Hitachi, Ltd. | Vacuum switch and vacuum switchgear using the same |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008090175A1 (en) * | 2007-01-24 | 2008-07-31 | Siemens Aktiengesellschaft | Electric direct current network for water vessels and for offshore units having increased shut-off security |
KR101140428B1 (en) | 2007-01-24 | 2012-04-30 | 지멘스 악티엔게젤샤프트 | Electric direct current network for water vessels and for offshore units having increased shut-off security |
EP2249363A1 (en) * | 2009-05-07 | 2010-11-10 | ABB Research Ltd. | Arrangement, substation, operating method and use of a grounding switch for protecting an electrical circuit against short-line faults |
DE102014213944A1 (en) * | 2014-07-17 | 2016-01-21 | Siemens Aktiengesellschaft | Electrical switching device for medium and / or high voltage applications |
US10102989B2 (en) | 2014-07-17 | 2018-10-16 | Siemens Aktiengesellschaft | Electric switching device for medium and/or high-voltage uses |
DE102016217625A1 (en) * | 2016-03-30 | 2017-10-05 | Siemens Aktiengesellschaft | High voltage component and device with a high voltage component |
US11527873B2 (en) | 2017-12-19 | 2022-12-13 | Abb Schweiz Ag | Inner compartment design for medium voltage switchgears |
Also Published As
Publication number | Publication date |
---|---|
US6884940B1 (en) | 2005-04-26 |
KR20050047460A (en) | 2005-05-20 |
US20050173143A1 (en) | 2005-08-11 |
CN1310266C (en) | 2007-04-11 |
TW200519999A (en) | 2005-06-16 |
CN1619745A (en) | 2005-05-25 |
JP4403782B2 (en) | 2010-01-27 |
US7244903B2 (en) | 2007-07-17 |
TWI240292B (en) | 2005-09-21 |
JP2005149926A (en) | 2005-06-09 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7244903B2 (en) | Vacuum switchgear | |
JP4162664B2 (en) | Vacuum switchgear | |
US8008594B2 (en) | Vacuum insulated switchgear | |
US6259051B1 (en) | Vacuum switch and a vacuum switchgear using the same | |
US11637414B2 (en) | Three phase switchgear using single phase equipment in single casing | |
WO2000021108A1 (en) | Vacuum switch and vacuum switch gear using the vacuum switch | |
KR100370485B1 (en) | Vacuum switch and vacuum switchgear using the same | |
CN106099656B (en) | High-voltage AC switch cabinet | |
JP4811331B2 (en) | Switchgear | |
US20020043515A1 (en) | Vacuum switch and vacuum switchgear using the same | |
CN110350437B (en) | Gas insulated switchgear and insulating spacer therefor | |
JPH1189027A (en) | Switch gear | |
JP3402135B2 (en) | Vacuum switch and vacuum switchgear | |
JP3775010B2 (en) | Switchgear | |
KR200384332Y1 (en) | Insulator Assembled with Lightning Arrester and Current Transformer Therein | |
JP2012138223A (en) | Cubicle-type gas insulated switchgear | |
JP2021027764A (en) | Insulated spacer and insulated switchgear | |
US20060237393A1 (en) | Gas insulated switching system or component of a gas insulated switching system comprising an open-air leadthrough | |
JP2005005277A (en) | Vacuum switch | |
JPS62225115A (en) | Gas insulated switchgear | |
JPH11113116A (en) | Switchgear | |
KR20040090052A (en) | Insulator Assembled with Lightning Arrester and Current Transformer Therein |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: HITACHI LTD., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:UTSUMI, TOMOAKI;SATOU, KAZUHIRO;SHIRONE, TAKASHI;AND OTHERS;REEL/FRAME:015675/0676 Effective date: 20040629 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
FEPP | Fee payment procedure |
Free format text: PAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20170426 |