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
  • H01H33/02—Details
  • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
  • H01H33/18—Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet
• • 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
  • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
  • H01H33/18—Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet
  • H01H33/187—Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet comprising a hollow annular arc runner and a central contact between which a radially drawn arc rotates
• • 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
  • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
  • H01H33/12—Auxiliary contacts on to which the arc is transferred from the main contacts
  • H01H33/121—Load break switches
  • H01H33/122—Load break switches both breaker and sectionaliser being enclosed, e.g. in SF6-filled container

Definitions

• the invention relates to an SF ⁇ gas-insulated switchgear for distribution networks with switch disconnector cable panels and a switch disconnector-fuse combination or a circuit breaker with a isolating section (circuit breaker) for transformer protection.
• Switchgear of this type is known.
• Medium-voltage switchgear with three switch panels is generally used in power distribution stations, two of which are connected with ring cables and one switch panel is equipped with high-voltage fuses or a circuit breaker for a transformer feeder.
• SFß gas-insulated switch disconnector arrangement in which the switch disconnectors are arranged in an encapsulated housing filled with sulfur hexafluoride (SF ⁇ ), a fixed and movable contact piece, an earth contact, and one out per phase Löschbleche ⁇ existing extinguishing device, and in which the fixed contact pieces of the same phases attached directly to a busbar and the extinguishing devices are each arranged next to them directly on the busbar.
• SF ⁇ sulfur hexafluoride
• the arc extinguishing devices arranged on the phases of the load-break switch or the circuit-breaker have the task of quickly extinguishing the arc which occurs on them and which, when switched off by opening the contacts and the evaporation of the last metal bridge by the heat of current. stands to ensure the switching ability of the switches. With alternating current, it is important to effectively reduce the charge carriers in the short time between a current zero crossing and the oscillation of the recurring voltage.
• quenching devices for electrical switching devices, including quenching coils into which the resulting arc is commutated and, as a result of the current then flowing through the coil, generates a magnetic field which causes the arc to rotate and finally be extinguished.
• EP 0 012 522 describes an electrical switching device with quenching coils on the fixed contacts.
• EP 0 021 577, EP 0 058 007 and EP 0 313 106 B1 also deal with electrical switching devices with quenching coils as arc quenching devices.
• the load-break switch of a switchgear panel is combined with a fuse attachment with high-voltage fuses with a striker, which may be encapsulated, the load-break switch being equipped with a memory drive with a trip memory which can be actuated by a striker of one of these fuses via a trigger linkage.
• the breaking capacity level of the nominal fuse current
• the associated fulfillment of the isolating path conditions with regard to the extinguishing plate arrangement used as the extinguishing device.
• Both the switch disconnector and the circuit breaker must be designed in such a way that they meet the isolating section conditions, that is, they have a required dielectric strength depending on the nominal voltage. Likewise, both switches must be designed so that they ensure their switching ability len by checking and extinguishing the switching arc in the shortest possible way.
• the generic switchgear comprises several switch panels with three-pole switch disconnectors and an earthing device, of which one switch panel is equipped with a switch disconnector designed as a transformer switch, the phases of which are combined with fuses, or can have a circuit breaker, and in which the fixed contacts of the phases L1, L2 and L3 are firmly connected to busbars on which quenching devices are arranged for the individual phases, the quenching devices for phases L1, L2 and L3 of the switch designed as a transformer switch having a switch contact arrangement corresponding to the other switches and quenching coils and the quenching devices for the phases of the invention other isolating switches are known extinguishing chambers with quenching plates.
• the isolating path conditions are met with a circuit breaker and the means for securing the switching capability - given the space available for the switches with arcing chambers and a switching contact arrangement corresponding to these - are provided if the arcing coils are arranged and designed such that their coil axis coincides with that in the switch-off position Switch contact on the fixed contact side forms an obtuse angle and the free end of the switch contact in the switch-off position lies in the area of the coil axis, that the coil radius corresponds at least to the distance between the switch contact in the switch-off position and the fixed contact and that the coil contact area on the fixed contact side has a minimum distance to the fixed contact and the free one End of the switching contact moved past.
• the isolating path conditions are met and the means for ensuring the switching capability are provided if the quenching coils are arranged and designed such that their coil axis has a right or obtuse angle on the fixed contact side with the switching contact in the switch-off position includes and the quenching coils each have a guide element which takes over the base point of the arc and extends into the immediate vicinity of the fixed contact and is arranged tangentially to the path of movement of the free end of the switching contact.
• the guiding element plays an important role in ensuring the switching capacity of the switch disconnector. It transports the arc that arises between the switch blade and the contact along the guide element into the coil.
• the guiding element therefore has the task of arranging the quenching coil, which is smaller in the case of a load break switch than in the case of a circuit breaker, at a distance from the busbar contact, and in this arrangement making it possible to change the arc into the quenching coil.
• the arrangement of quenching coils on the transformer switch leads to an increased switch-off capacity of the switchgear for a given unchanged arrangement space, whereby the increased requirements for switch-disconnector-fuse combinations or also the switching off of short-circuit currents can be taken into account, and thus represents a significant technical advance.
• the quenching coil and the fixed contact for the respective phase L1, L2 and L3 can expediently be arranged on a common cross member, which is connected to the busbar for the respective phase and to which the movable switching contact is pivotally arranged, such that it is out of the at the switch-on position given in the fixed position into a switch-off position parallel to the crossmember and beyond this into a grounding position.
• the quenching coils can be arranged so that their coil axis forms an obtuse angle, preferably 165 ° to 175 °, on the side facing the fixed contact with the switch contact in the switch-off position. or is arranged perpendicular to the switch contact in the switch-off position.
• the fixed contact is in the center of the quenching coil and the guide element is directed into the inside of the coil.
• the free ends of the movable switch contacts and the tear-off edges of the fixed contacts can be provided with caps and erosion strips, which are made of more erosion-resistant material than the respective contact material.
• the quenching coils and the quenching chambers can be connected to an assembly that can be inserted into the housing, which is initially open on the rear.
• This assembly can be formed from the busbars, the fixed contacts fastened to them with cross members, supports for the cross members and holding devices for arrangement on the housing.
• the three earthing contacts belonging to the earthing device are attached to the switch shafts.
• Fig. 1 an SF6 gas-insulated switchgear according to the invention in plan view
• Switch disconnector (Switch disconnector), Fig. 2: the switchgear in rear view (circuit breaker), Fig. 3: a phase of the switch disconnector combined with fuses, Fig. 4: another version of a phase of the combination with fuses
• Switch-disconnector and Fig. 5 a different fixed and switching contact version at one
• the gas-insulated switchgear consists of a gas-tight housing 1, in which three switch panels I, II and III are housed, each with a three-pole switch disconnector and an earthing device.
• the control panel I houses one Switch disconnectors designed as transformer switches, the phases L1, L2 and L3 of which are combined with fuses (not shown) via bushings 2.
• the switch disconnectors have switching knives 3, which are designed as double knives, as movable switching contacts.
• the switching knives 3 each rest directly on the respective bushings 2, for the phases L1 and L3 special switching knife supports are used, which are connected to the associated bushings 2 by bearing pieces (not shown).
• the bushings 2 are all located on the front side 4 of the housing 1.
• the switching knives 3 are actuated via a switch shaft 5 mounted on the walls of the housing 1, which is connected to the switching knife 3 via a lever 6 and a coupling rod 7.
• a ground contact 8 is connected directly to the switch shaft 5.
• the switching knife 3 can take three positions. In the switched-on state, the respective switch blade 3 contacts a fixed contact 10 which is fixedly connected to a busbar 9. The switched-on state is shown in switch panel III. In the switched-off state, the respective switching knife 3 is brought into a position which lies between the fixed contact 10 and the ground contact 8. This switching state is shown in panel II. In the earthed state, the respective switch blade 3 contacts the earth contact 8, shown in the control panel I.
• the housing 1 there are three busbars 9, on each of which the fixed contacts 10 of the respective phases L1, L2 and L3 of the switch disconnectors are arranged. Furthermore, quenching devices are arranged on the busbars 9 for each phase L1, L2 and L3, of which the quenching devices on the phases of the fuse-free switch disconnectors of switch panels II and III are equipped with quenching chambers 12 and the quenching devices on the phases of the switch disconnector combined with the fuses of the control panel I are quenching coils 13a. These (13a) and the fixed contacts (10) are arranged on a cross member 14 connected to the respective busbar 9, to which the switching blades 3 are aligned in parallel in the switch-off position. The quenching coils 13a are arranged such that their coil axis A with the switching Contact 3 on the side facing the fixed contact 10 includes an obtuse angle ⁇ of approximately 165 ° (FIG. 2).
• the quenching coils 13a and the quenching chambers 12 are together with the busbars 9, the fixed contacts 10 arranged on cross members 14 and, via these, firmly connected to the busbars 9, supports 15 for the cross members 14, holding devices 16 and struts 18 for arrangement on the housing 1 to form a structural unit joined together, which can be inserted into the housing 1 via the rear side 19 before the same is closed in a gas-tight manner.
• the quenching coils 13a each have a baffle 17 electrically connected to the end of the coil winding in the immediate vicinity of the respective fixed contact 10, which has the width of a switching knife 3 and is arranged tangentially to the movement path of the free end thereof.
• control panel I circuit breaker
• Fig. 3 the arrangement of an erase coil 13a is shown enlarged on one phase.
• the quenching coil 13a is held on a tab 20 which is electrically coupled both to the start of the quenching coil 13a and to the cross member 14 and thus to the busbar 9.
• Fig. 4 shows an alternative quenching coil arrangement for the same switchgear, in which the quenching coils 13a are arranged on a tab 21 such that the coil axis A forms a right angle ⁇ with the switch blade 3 in the switched-off position, the quenching coils 13a enclosing the fixed contacts 10 .
• the quenching coils 13a in turn have a baffle 17 electrically connected to the end of the coil winding in the immediate vicinity of the respective fixed contact 10 on, which has the width of a switching knife 3 and is arranged tangentially to the movement path of the free end thereof.
• the free ends of the switch blades 3 can be provided with caps 22 for higher breaking currents to increase the resistance to erosion
• the fixed contacts 10 can be provided with erosion bars 23.
• the material of the caps 22 and the erosion bars 23 is more resistant to erosion than the base material of the respective contact 3 or 10 (FIG. 5).

Landscapes

• Arc-Extinguishing Devices That Are Switches (AREA)
• Gas-Insulated Switchgears (AREA)
• Organic Insulating Materials (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7801988

Family Applications (1)

Country Status (11)

Cited By (3)

Families Citing this family (4)

Citations (4)

Family Cites Families (4)

• 1996
  • 1996-08-07 DE DE19631817A patent/DE19631817C1/de not_active Expired - Fee Related
• 1997
  • 1997-08-04 CZ CZ0037999A patent/CZ296238B6/cs not_active IP Right Cessation
  • 1997-08-04 WO PCT/EP1997/004241 patent/WO1998006120A1/de active IP Right Grant
  • 1997-08-04 ES ES97938873T patent/ES2174281T3/es not_active Expired - Lifetime
  • 1997-08-04 EP EP97938873A patent/EP0917721B1/de not_active Expired - Lifetime
  • 1997-08-04 BR BR9710807-3A patent/BR9710807A/pt not_active Application Discontinuation
  • 1997-08-04 AT AT97938873T patent/ATE216126T1/de not_active IP Right Cessation
  • 1997-08-04 CN CNB971970599A patent/CN1205633C/zh not_active Expired - Fee Related
• 1999
  • 1999-02-04 KR KR1019997000954A patent/KR100297622B1/ko not_active Expired - Fee Related
  • 1999-02-04 NO NO19990532A patent/NO317118B1/no not_active IP Right Cessation
  • 1999-02-05 PL PL97331466A patent/PL187349B1/pl not_active IP Right Cessation

Patent Citations (4)

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