EP0095406B1 - Interrupteur à arc tournant et à aimant permanent - Google Patents
Interrupteur à arc tournant et à aimant permanent Download PDFInfo
- Publication number
- EP0095406B1 EP0095406B1 EP19830400933 EP83400933A EP0095406B1 EP 0095406 B1 EP0095406 B1 EP 0095406B1 EP 19830400933 EP19830400933 EP 19830400933 EP 83400933 A EP83400933 A EP 83400933A EP 0095406 B1 EP0095406 B1 EP 0095406B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- magnet
- contact
- permanent magnet
- contacts
- path
- 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.)
- Expired
Links
- 230000005291 magnetic effect Effects 0.000 claims description 15
- 230000005347 demagnetization Effects 0.000 claims description 12
- 230000005415 magnetization Effects 0.000 claims description 10
- 238000000926 separation method Methods 0.000 claims description 10
- 239000011796 hollow space material Substances 0.000 claims description 4
- 239000007789 gas Substances 0.000 description 11
- 238000007664 blowing Methods 0.000 description 7
- 238000005192 partition Methods 0.000 description 7
- 229910018503 SF6 Inorganic materials 0.000 description 4
- SFZCNBIFKDRMGX-UHFFFAOYSA-N sulfur hexafluoride Chemical compound FS(F)(F)(F)(F)F SFZCNBIFKDRMGX-UHFFFAOYSA-N 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000004323 axial length Effects 0.000 description 2
- 230000008033 biological extinction Effects 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 239000011810 insulating material Substances 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 229960000909 sulfur hexafluoride Drugs 0.000 description 2
- 230000003042 antagnostic effect Effects 0.000 description 1
- 230000002457 bidirectional effect Effects 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 230000013011 mating Effects 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 230000037452 priming Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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
- H01H33/02—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
- H01H33/182—Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet using permanent magnets
Definitions
- Document EP-A-37 765 relates to such a switch, and the permanent magnet is disposed inside a hollow conductive cylinder forming the fixed contact.
- the current flowing through the fixed contact and the supply circuit does not pass through the permanent magnet and does not generate any magnetic field capable of demagnetizing the magnet housed inside the fixed contact.
- the hollow cylinder of the fixed contact is provided with an annular rim disposed opposite a mating annular surface of the movable contact to cooperate by abutment in the closed position.
- the rotary arc switch comprises two permanent annular magnets with radial magnetization and coaxially surrounding the separable contacts.
- the flow of current through the contacts causes a magnetic field of demagnetization inside each magnet.
- This type of switch is mainly used for breaking low currents, but it is unable to cut high currents, for example greater than 15 kA.
- To reduce the demagnetization effect of the magnet it has already been proposed according to FIG.
- the fixed and movable contacts are formed by hollow cylinders equipped with annular flanges coming into contact by abutment. Each cylinder is placed inside a permanent magnet, and the current is supplied by means of a conductive rod secured to the movable contact.
- connection pads located axially on the same side with respect to the contact separation zone, with a risk of priming between the central current supply rod and the hollow cylinder associated with the fixed contact.
- the present invention aims to allow the production of a reliable switch whose permanent magnet causing the rotation of the arc is protected from any demagnetization field regardless of the intensity of the current to be interrupted.
- the switch according to the invention is characterized in that the permanent magnet is hollow while being crossed by one of the contacts, and in that the contact concerned is electrically connected to said first path of the current supply circuit disposed at the outside of said permanent magnet by a second path of the current supply circuit, said second path being disposed inside the hollow space of said magnet, so as to avoid any demagnetization field inside said hollow space said permanent magnet.
- the second path of the current supply circuit comprises a U-shaped rim with a hairpin axial section extending along the internal face of the permanent magnet, the current flowing in opposite directions in the substantially parallel branches of the pin.
- the second current path is advantageously formed by an internal ferrule one end of which is connected to the first external path and the opposite end of which is connected to a contact support tube or sleeve, the internal ferrule being arranged coaxially between the magnet and the tube or sleeve.
- One of the contacts surrounded by a first permanent magnet can be fixed and has an annular contact end arranged in the vicinity (projecting or recessed) of the front front face of the magnet.
- This contact can also be semi-fixed by being connected to the internal ferrule by means of a sliding contact or a contact clamp.
- the other movable contact in translation passes axially through a second permanent fixed magnet and is electrically connected to the corresponding internal ferrule of the circuit by a sliding contact, the second magnet being placed opposite the first magnet and separated from the latter by a predetermined axial interval.
- the magnetization of the permanent magnet (s) can be arbitrary, either radial or axial homopolar, or heteropolar.
- the envelope is filled with an electronegative gas such as sulfur hexafluoride, and according to an important development of the invention, the magnetic blowing of the arc by the action of the permanent magnet (s) is combined with a pneumatic blowing. by self-expansion of compressed gases liable to escape through hollow contacts.
- a pole of a switch 10 or of a rotary arc circuit breaker comprises a sealed casing 12 of molded insulating material, filled with insulating gas 13 of high dielectric strength, in particular sulfur hexafluoride.
- the cylindrical casing 12 has an elongated shape, the upper part of which is closed off by a bottom 14 made of conductive material and with a radial tab shaped as a field 16 for supplying current.
- a fixed contact 18 cooperating with a movable contact 20 aligned and mounted to slide axially by means of an actuating rod of a control mechanism (not shown).
- the fixed contact 18 in the form of a hollow cylinder with a diameter equivalent to that of the movable contact 20, is coaxially surrounded by a permanent and annular fixed magnet 22.
- the permanent magnet 22 with radial magnetization generates in the arc zone a permanent radial magnetic field causing the rotation of the arc during the separation of the contacts 18, 20.
- the end of the fixed contact 18 being in abutment with the movable contact 20 in the closed position, protrudes from the front end face 24 of the permanent magnet 22.
- a current supply circuit 26 ensures the electrical connection of the fixed contact 18 with a central stud 28 of conductive material secured to the bottom 14.
- the circuit 26 for supplying current to the tubular fixed contact 18 is formed by an annular conductive carcass of revolution about the longitudinal axis and having a recess 30 for housing the permanent magnet 22.
- the carcass of the circuit 26 is shaped in loop surrounding the four faces of the annular permanent magnet 22, and comprises a conductive copper base with a U-section constituted, for example, by the assembly of two internal coaxial ferrules 32 and external 34 to an annular washer 36 covering the front face 24 anterior of the magnet 22.
- the external ferrule 34 is connected to the central stud 28 by a conductive ring 38 extending parallel to the front face 40 posterior of the magnet 22 with the interposition of a ferromagnetic plate 42, by steel example.
- the internal ferrule 32 Opposite the washer 36, the internal ferrule 32, isolated from the ring 38 and the stud 28, is secured to a tube 44 supporting the fixed contact 18 so as to form an annular flange 45 with an inverted U-shaped pin section. , said flange 45 being housed in the cylindrical internal space of the permanent magnet 22.
- the internal ferrule 32 is interposed coaxially between the cylindrical lateral face 46 internal of the magnet 22 and the tube 44 made of metallic material, in particular copper or steel.
- a thin sleeve (not shown) of insulating material can be inserted axially in the radial interval 48 of the inverted flange 45:
- the circuit 26 for supplying current to the fixed contact 18 forms with the permanent magnet 22 and the stud 28 an assembly monobloc carried by the bottom 14.
- the permanent magnet 22 is constituted by a ferrite magnet or a metallic magnet, and an insulating layer (not shown) can be interposed between the magnet 22 and the annular conducting carcass of the circuit 26.
- the circuit 26 for supplying current to the fixed contact 18 has a first path outside the magnet, connected in series with a second path inside the annular magnet 22.
- the first path includes the ring 38, the outer ring 34 and the washer 36 which respectively cover the plate 42 of the posterior front face 40, the external cylindrical side face 50, and the front front face 24 of the permanent magnet 22.
- the second path includes the inverted rim 45 formed by the internal ferrule 32 associated with the tube 44 supporting the fixed contact 18.
- the current flowing through the ring 38, the ferrule 34 and the washer 36 of the first external path does not pass through the annular permanent magnet 22 and does not generate any magnetic field capable of demagnetizing the magnet 22.
- the ferrule 32 and the tube 44 of the second internal path are separated by the small radial interval 48 and are traversed in the opposite axial direction by the current. This results in compensation for the magnetic fields generated in the internal cylindrical space of the magnet 22 by the passage of current through the ferrule 32 and the tube 44.
- the permanent magnet is thus protected from any demagnetization field , even in the presence of short-circuit currents of high intensity, for example greater than 20 kA.
- the permanent magnet 22 generates a magnetic field which is permanently present in the breaking zone as soon as the contacts 18, 20 are separated.
- the switch is opened by sliding the movable contact 20 downwards (see half-section left of Fig. 1), and the arc drawn between the contacts 18, 20 extends substantially in the axial direction.
- the magnetic field of the permanent magnet 22 causes, in a well known manner, the rotation of the arc on the annular tracks of the hollow contacts 18, 20. It should be noted that the axial protrusion of the fixed contact 18 relative to the washer 36 of the conductive carcass maintains the arc roots on the annular tracks of the contacts 18, 20.
- FIG. 2 represents an alternative embodiment, in which the axial length of the tube 44 supporting the fixed contact 18 is shortened so as to position the fixed contact 18 set back or in the vicinity of the washer 36.
- the passage of the current in the supply circuit 26 is identical to that of the device in FIG. 1, and no demagnetization field affects the magnetization of the permanent magnet 22 thanks to the axial outward and return path of the current in the ferrule 32 and the tube 44.
- the arc of the fixed contact 18 is switched to the washer 36, which then plays the role of an annular migration path of the rotating arc.
- the current flows only in the first path of the circuit 26.
- the arc turns in the SF6 gas under the action of the field of the magnet around the washer 36 and the annular end of the movable contact 20, the internal ferrule 32 and the tube 44 not being traversed by any current.
- FIG. 3 illustrates another alternative embodiment in which the same reference numbers are used to designate identical or similar parts to those of FIGS. 1 and 2.
- the magnetic blowing by rotation of the arc is accompanied by a double pneumatic blowing due to the thermal expansion of the gas generating a gas flow escaping through the fixed tubular contacts 18 and movable 20.
- the interrupting chamber 54 of the switch 10 is separated from the casing 12 by an intermediate casing 56 constituted by a cylindrical wall coaxial with the casing 12, and transverse shutter partitions 58, 60.
- the upper insulating partition 58 is crossed axially by the fixed stud 28 of tubular shape and with radial opening 62 formed between the bottom 14 and the partition 58.
- the movable contact 20 is integral with a conductive sleeve 63 mounted to slide axially through a orifice in the lower partition 60, said sleeve 63 actuated by means of a control rod 64 sealingly passing through the conductive bottom 66 connected to a connection pad 68.
- the sleeve 63 has radial openings 70 arranged between the partition 60 and the bottom 66.
- the two areas 16, 68 for connecting the switch are arranged on either side of the contact separation zone.
- the fixed contact 18 is surrounded inside the breaking chamber 54 by the annular permanent magnet 22 and the current supply circuit 26 as described with reference to FIG. 1.
- the arc rotating under the action of the field of the magnet 22 causes, in a well known manner, the rise in pressure of the gas inside the interrupting chamber 54. This results in a gas flow which promotes extinction. from the arc, the gas escaping taking place towards the envelope 12 in opposite directions respectively through the fixed tubular contact 18 and the opening 62 of the stud 28, and through the movable contact 20 and the openings 70 of sleeve 63.
- the magnetic blowing of the arc can be reinforced by using in the device of fig. 3 a second permanent magnet 72 coaxially surrounding the movable contact 20 inside the breaking chamber 54, and arranged opposite the first permanent magnet 22 associated with the fixed contact 18.
- the second magnet 72 is fixed and axially separated from the first magnet 22 by a predetermined interval corresponding substantially to the axial length of the cut-off zone.
- the movable contact 20 passes through the second annular permanent magnet 72, and is electrically connected to the bottom 66 of the connection pad 68 by means of a connection circuit 74 arranged to avoid demagnetization of the magnet 72.
- the circuit of link 74 is similar to the circuit 26 for supplying current to the fixed contact 18, and comprises a sliding contact 76 formed at the level of the partition 60 between the sliding sleeve 63 and a coaxial conductive socket 78.
- the internal diameter of the sleeve 78 corresponds substantially to the external diameter of the sleeve 63 with the interposition of a radial clearance allowing the bidirectional axial sliding of the sleeve 63.
- the sleeve 78 extends along the internal side face of the magnet 72 and is electrically connected to a loop surrounding the magnet 72.
- the loop is formed by an annular conductive carcass, of structure identical to that associated with the magnet 22 of FIG.
- the extinction of the arc is facilitated by the reinforcement of the magnetic field in the breaking zone, resulting from the sum of the elementary radial fields of the two magnets 22, 72.
- the magnetic blowing is combined with a pneumatic blowing by expansion of the SF6 gas through the tubular contacts 18, 20 in the direction of the casing 12.
- the contact 18 instead of being fixed could be arranged in a semi-fixed manner thanks to the addition of an elastic means and a clamp or a sliding contact between the internal ferrule 32 and the contact 18.
- the magnetization of the permanent magnet (s) 22, 72 is axial, but it is clear that the structure and the magnetization of the magnet can be arbitrary, in particular heteropolar or radial magnetization.
Landscapes
- Arc-Extinguishing Devices That Are Switches (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8208536 | 1982-05-13 | ||
| FR8208536A FR2526998A1 (fr) | 1982-05-13 | 1982-05-13 | Interrupteur a arc tournant et a aimant permanent |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0095406A1 EP0095406A1 (fr) | 1983-11-30 |
| EP0095406B1 true EP0095406B1 (fr) | 1986-01-22 |
Family
ID=9274087
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP19830400933 Expired EP0095406B1 (fr) | 1982-05-13 | 1983-05-09 | Interrupteur à arc tournant et à aimant permanent |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0095406B1 (enExample) |
| JP (1) | JPS58204430A (enExample) |
| DE (1) | DE3361907D1 (enExample) |
| FR (1) | FR2526998A1 (enExample) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2609837B1 (fr) * | 1987-01-19 | 1989-04-14 | Merlin Gerin | Disjoncteur polyphase a autoexpansion equipe d'une chambre de coupure blindee par pole |
| JP3605564B2 (ja) * | 2000-12-28 | 2004-12-22 | 日本圧着端子製造株式会社 | 接続用端子及びこの端子の回路基板への取付け方法 |
| FR2824182A1 (fr) * | 2001-04-26 | 2002-10-31 | Alstom | Disjoncteur a arc tournant a aimant permanent |
| JP4753360B2 (ja) * | 2005-10-28 | 2011-08-24 | Necトーキン株式会社 | 電気接点開閉部 |
| CN100536054C (zh) * | 2007-06-08 | 2009-09-02 | 华中科技大学 | 旋转电弧脉冲功率开关 |
| CN101908438A (zh) * | 2010-07-23 | 2010-12-08 | 沈阳铁路信号工厂 | 不对称永磁灭弧装置 |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3082307A (en) * | 1959-04-30 | 1963-03-19 | Gen Electric | Vacuum type circuit interrupter |
| DE1236628B (de) * | 1961-05-17 | 1967-03-16 | Bbc Brown Boveri & Cie | Elektrischer Schalter, insbesondere Schuetz |
| GB1078863A (en) * | 1964-08-12 | 1967-08-09 | English Electric Co Ltd | Improvements in or relating to circuit interrupters |
| FR2480028A1 (fr) * | 1980-04-04 | 1981-10-09 | Merlin Gerin | Interrupteur a arc tournant par action d'un aimant permanent |
-
1982
- 1982-05-13 FR FR8208536A patent/FR2526998A1/fr active Granted
-
1983
- 1983-05-09 EP EP19830400933 patent/EP0095406B1/fr not_active Expired
- 1983-05-09 DE DE8383400933T patent/DE3361907D1/de not_active Expired
- 1983-05-11 JP JP8346083A patent/JPS58204430A/ja active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58204430A (ja) | 1983-11-29 |
| FR2526998A1 (fr) | 1983-11-18 |
| FR2526998B1 (enExample) | 1985-02-15 |
| DE3361907D1 (en) | 1986-03-06 |
| EP0095406A1 (fr) | 1983-11-30 |
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