WO2005074084A1 - 火花ギャップアレスタ - Google Patents
火花ギャップアレスタ Download PDFInfo
- Publication number
- WO2005074084A1 WO2005074084A1 PCT/JP2005/000991 JP2005000991W WO2005074084A1 WO 2005074084 A1 WO2005074084 A1 WO 2005074084A1 JP 2005000991 W JP2005000991 W JP 2005000991W WO 2005074084 A1 WO2005074084 A1 WO 2005074084A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- arc
- current
- extinguishing
- arrester
- lightning
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
- H02H9/06—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage using spark-gap arresters
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
- H01T1/00—Details of spark gaps
- H01T1/02—Means for extinguishing arc
- H01T1/04—Means for extinguishing arc using magnetic blow-out
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
- H01T4/00—Overvoltage arresters using spark gaps
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
- H01T4/00—Overvoltage arresters using spark gaps
- H01T4/10—Overvoltage arresters using spark gaps having a single gap or a plurality of gaps in parallel
- H01T4/12—Overvoltage arresters using spark gaps having a single gap or a plurality of gaps in parallel hermetically sealed
Definitions
- the present invention relates to an arrester structure that is installed in a low-voltage AC power supply circuit to protect electronic devices that are sensitive to overvoltage during a lightning strike, and that bypasses and discharges lightning current to the ground. It is.
- a main metal part for example, a steel frame, a reinforcing bar, or the like
- a base ground Provide one or more grounding buses inside the building, connect them to the basic grounding at the shortest distance, and bring in metal pipes (for example, water pipes, gas pipes, etc.) and electric wires (distribution lines, telephone wires, antenna wires, etc.) that are drawn in from outside.
- metal pipes for example, water pipes, gas pipes, etc.
- electric wires distributed lines, telephone wires, antenna wires, etc.
- Non-Patent Document 4 International standards for lightning currents during lightning strikes present the current values, waveforms, and charge amounts shown in Table 1.
- Fig. 1 shows an example in which internal lightning protection specified in Non-Patent Document 3 is applied to a low-voltage power distribution system of a general building.
- a lightning strike strikes point 31 on building 10
- lightning current 32 is released to the ground (lightning current 33) via the metal structure of the building or the lightning conductor, but the potential of the entire building is reduced due to the ground resistance R1 of the building foundation.
- R1 10 Q and 50 kA of the lightning current peak value of 100 kA flows to R1
- the potential of the entire building is 500 kV.
- the bonding bar 11 connected to the building foundation ground also has the same potential, and far exceeds the normal potential of low-voltage distribution lines (about 300 V or less with respect to the ground).
- a part (lightning current 34) flows.
- the lightning current 34 flows through each conductor of the distribution line (lightning current 35), and is finally discharged from the neutral point of the secondary winding 21 of the distribution transformer 20 to the ground via the grounding resistor R2 ( Lightning current 36).
- the shunt ratio of the lightning currents 33 and 36 is approximately 1: 1
- the impulse current peak value per pole of the arrester 12 is assumed to be about 1/6 of the lightning current 32 (lightning current When the peak value is 100kA, it is about 17kA).
- the lightning current arrester installed at the distribution line entrance must have an impulse current capability of 20 kA or more with an impulse current waveform of 10/350 ⁇ s.
- An arrester that has been most frequently used in the past to limit overvoltage generated in a distribution line has been a device mainly composed of a varistor element made of suboxide ii.
- Oxide sub-varistor Figure 2 shows the current and voltage waveforms when the impulse current flows in Fig. 2.
- Zinc oxide varistors can select a relatively small value of the ratio between the limit voltage and the maximum supply voltage (limit voltage / maximum supply voltage) that does not delay the overvoltage limit with respect to the impulse current with a fast rise speed.
- limit voltage / maximum supply voltage limit voltage / maximum supply voltage
- the varistor terminal voltage is maintained at several hundreds of volts during the impulse current flow, so that the energy conversion inside the varistor is large. In this case, it cannot be used as a lightning current arrester because it is easily damaged or ruptured.
- Table 2 shows the relationship between the varistor's critical load value (can be loaded once without breaking) and the varistor diameter at an impulse current of 10/350 x s.
- An arrester having a spark gap as a main element has essentially overvoltage switching characteristics (see FIG. 3). When the overvoltage exceeds the gap firing voltage, the spark gap breaks over and starts arcing.
- the arc voltage is about several tens of volts, and the amount of energy conversion inside the arrester when lightning discharge current flows is small. Therefore, by selecting a material and structure that can withstand high temperatures, there is a possibility that it can be used as a lightning current arrester.
- Fig. 4 shows the basic structure of the spark gap arrester disclosed in Reference 1. All the components are arranged in a rotationally symmetric structure with respect to the central axis, and the two main electrodes la and lb are opposed to each other with a certain gap by the cylindrical insulator 2. When an impulse voltage exceeding the withstand voltage of the gap is applied, spark discharge starts between the gaps and shifts to arc discharge.
- the high-current arc discharge causes rapid ionization and expansion of the air inside the arrestor, but the outside of the case consisting of the cylindrical insulator 3, the heat insulation plates 4a and 4b, and the lid members 5a and 5b is covered with a metal pipe 6 It is covered by, and both sides are firmly closed by Carling Kaloe, so that even if the internal pressure exceeds tens of atmospheres, it can not explode or be damaged.
- the duration of the impulse current is as short as lms or less, and the heat capacity of the metal parts is sufficiently large so that no excessive temperature rise occurs. Therefore, the problem 2) in the previous section is solved by this sealing structure.
- 7a and 7b are lead conductors screwed into the electrodes la and lb.
- FIG. 5 shows the relationship between the arc current I and the arc voltage U.
- FIG. 6 shows a follow-up waveform when an impulse current flows through the arrester at a phase angle of 60 ° (a momentary voltage value of about 270 V) of a 220 V power supply voltage.
- the current waveform becomes a current waveform and the power supply restart voltage at the zero current point is 60 V or less, the follow-up current disappears at this point.
- the impedance of the power supply circuit and the arc resistance are small, the current waveform of the continuation current 2 is obtained, and the power supply restart voltage at the zero current point is 60 V or more.
- Patent Document 1 European Patent Application Publication No. 78434
- Non-Patent Document 1 DIN VDE 0185 Part 100 "Regulations and General Principles for Building Lightning Protection”
- Non-Patent Document 2 IEC 61024-1 (1990) "Protection of structures against lightning Part 1"
- Non-patent document 3 JIS A 4201-2003 ⁇ Lightning protection for buildings, etc. ''
- Non-Patent Document 4 IEC 61312-1 (1995) "Protection against lightning electromagnetic impulse Part 1 General principles
- an object of the present invention is to provide a spark gap arrester having a sealed structure arrester that prevents re-ignition after passing a lightning current and has no follow-up current.
- the voltage drop which does not depend on the arc current, can be obtained by inserting a metal plate into the arc discharge path, cutting the arc, and generating anode and power source voltage drops on both surfaces of the metal plate, respectively. . Since the voltage drop obtained by a pair of anode and power source electrodes is about 60V, assuming a power supply voltage of 200V, it is necessary to add a minimum of four metal plates to obtain a voltage drop of 300V.
- an arc-extinguishing insulating material (polyacetal, polypropylene, or the like) is arranged adjacent to the arc discharge path to prevent thermal decomposition of the insulating material when an arc is generated. It is effective to use the arc-extinguishing gas that is spouted.
- a lightning impulse current and / or lightning impulse current is generated by arranging a plurality of magnetic metal rings concentric with the circular cross section of a conical or cylindrical electrode as an arc-extinguishing plate.
- the voltage drop between the anode and the cathode of the arc generated by the power supply circuit follow-up is increased, and the follow-up self-interruption performance independent of the power supply impedance is obtained.
- the base of both discharge electrodes is made of a normal conductive material such as copper or brass, and only the tip is made of a heat-resistant or arc-resistant material such as copper tungsten or silver tungsten. According to the embodiment, the function of the arrester can be guaranteed while suppressing the material cost.
- the gap size can be defined with high accuracy while simplifying the assembling work.
- the arc-extinguishing plate is covered with the organic arc-extinguishing insulating material of the base from both ends of the two discharge electrodes, and is disposed over a part of the arc, the arc generated between the two discharge electrodes Can be completely transferred to the arc extinguishing plate, and the arc can be reliably extinguished.
- the magnetic permeability of the magnetic material can be increased and the attractive force to the arc discharge path can be increased.
- FIG. 1 An internal lightning protection circuit in a low voltage distribution system of a general building specified in JIS A 4201-2003.
- FIG. 2 shows current and voltage waveforms of zinc oxide paris.
- FIG. 3 shows the current and voltage waveforms of the spark gap.
- FIG. 4 shows the structure of a conventional encapsulated spark gap arrester.
- FIG. 5 shows current and voltage characteristics of arc discharge.
- FIG. 6 shows an impulse current and a follow-on waveform in an AC power supply circuit.
- FIG. 7 shows a sectional view of a self-extinguishing arrester according to the present invention.
- FIG. 8 shows an air gap provided in a magnetic metal ring.
- FIGS. 7 and 8 the structure and function of the arrester for a low-voltage AC power supply circuit according to the present invention will be described in detail.
- FIG. 7 is a vertical cross-sectional view of the cylindrical enclosing arrester.
- the parts are manufactured and arranged in a rotationally symmetrical manner with respect to the central axis.
- Both discharge electrodes are made of copper members 102a and 102b whose bases are ordinary conductors and copper tungsten tips 101a and 101b whose tips are excellent in heat resistance and arc resistance.
- the bases 102a, 102b and the tip portions 101a, 101b are integrated without performing a troublesome process such as brazing by fitting a projection of the tip portion into a recess provided in the base portion.
- the concave and convex portions at the base and the tip may be in the reverse combination.
- the discharge electrode has a conical shape in this embodiment.
- the discharge electrode may have a cylindrical shape. Both discharge electrodes are housed in a metal pipe 306 together with an insulator 301, insulating plates 305a and 305b, and insulating caps 304a and 304b. Both ends of the metal pipe are bent inward by a curling cable, and an axial pressure is applied to the flanges 103a and 103b of the copper electrodes to form a strong pressure-resistant structure.
- the size of the spark gap between the electrodes is automatically determined by the difference between the thickness of the insulator 301 and the sum of the depths of the concave portions provided at the end faces of the copper tungsten chips 101a and 101b, which is troublesome. No adjustment is required.
- the external lead portions of the copper electrode have terminal screws 104a and 104b, which are used to connect to external conductors.
- the space around the electrode is an arc chamber 106, which is filled with a high-temperature, high-pressure gas during arc discharge, so that the copper electrode is provided with exhaust pipes 105a, 105b to balance the pressure with the outside air.
- an insulating pipe 302 made of an organic arc-extinguishing insulating material, for example, polyacetal or polypropylene is arranged outside the insulator 301.
- the pipe 302 is decomposed by the heat generated when an arc discharge (arc a) is generated in the spark gear and blows out the arc-extinguishing gas, and the arc leg is positioned outside the gap and the conical surface of the electrodes 101a and 101b. (Arc b).
- n pieces of metal magnetic material arc extinguishing plates 201 to 209 concentric with the circular cross sections of the conical electrodes 101a and 102a and 101b and 102b, in this embodiment, are arranged.
- the metal magnetic body may be, for example, soft iron. Since the central arc-extinguishing plate 205 is located closest to the gap, the suction acting between the arc discharge path and the inner edge of the ring is reduced. Due to the force, the arc discharge path shifts outward, and first, the arc extinguishing plate 205 enters the inside of the arc discharge path, and a cathode and an anode for arc discharge are formed on both surfaces thereof (arc c).
- the arc discharge path is maintained even when the impulse current exceeds the peak value and enters the decay process.
- the power current value becomes substantially 0, if the instantaneous power supply voltage V is smaller than the arc voltage, the power supply
- the impulse current value is relatively small, the impulse current may disappear at the stage of arc a or b. In this case, there is a possibility that continuation of current from the power supply will occur because the arc voltage does not increase sufficiently.
- the arc due to the impulse current the arc due to the follow-up current is transferred to the outer surface of the gear and to the conical surfaces of the discharge electrodes 101a and 101b by the arc-extinguishing gas ejected from the insulating pipe 302 made of an organic arc-extinguishing insulating material. (Arc b), and the arc moves to arcs c and d by the attraction force from the arc extinguishing plate.
- the continuation current rapidly decreases and disappears near the zero point of the AC voltage. Because the arc resistance is large enough, even if the source impedance is sufficiently small, the follow-on current has the waveform of follow-on 1 shown in Fig. 6, and can be cut off within 1Z2 cycle.
- the discharge electrode, the arc-extinguishing insulating member, and the arc-extinguishing magnetic substance ring are all arranged in a rotationally symmetric structure, the self-extinguishing function of the arc is maintained regardless of the initial spark discharge generated at any position of the main electrode.
- a stepped cross section spacer ring 311 is used.
- a part of the metal ring is cut out as shown in FIG. 8, and an air gap 312 is provided in the magnetic path. If the remanence of the magnetic metal ring decreases, the change in magnetic flux inside the magnetic material can be increased when an impulse current flows near the magnetic material, increasing the magnetic permeability of the magnetic material and reducing the attractive force to the arc discharge path. Can be bigger.
Landscapes
- Thermistors And Varistors (AREA)
- Emergency Protection Circuit Devices (AREA)
- Arc-Extinguishing Devices That Are Switches (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/588,075 US20070183112A1 (en) | 2004-02-02 | 2005-01-26 | Spark gap arrestor |
JP2005517451A JPWO2005074084A1 (ja) | 2004-02-02 | 2005-01-26 | 火花ギャップアレスタ |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2004-025367 | 2004-02-02 | ||
JP2004025367 | 2004-02-02 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2005074084A1 true WO2005074084A1 (ja) | 2005-08-11 |
Family
ID=34823980
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2005/000991 WO2005074084A1 (ja) | 2004-02-02 | 2005-01-26 | 火花ギャップアレスタ |
Country Status (5)
Country | Link |
---|---|
US (1) | US20070183112A1 (ja) |
JP (1) | JPWO2005074084A1 (ja) |
KR (1) | KR20060129367A (ja) |
CN (1) | CN1918760A (ja) |
WO (1) | WO2005074084A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013186909A1 (ja) * | 2012-06-15 | 2013-12-19 | 合資会社シーエスディ | 火花ギャップアレスタ |
JPWO2013186951A1 (ja) * | 2012-06-15 | 2016-02-01 | 合資会社シーエスディ | 火花ギャップアレスタ |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101311686B1 (ko) * | 2006-03-29 | 2013-09-25 | 미츠비시 마테리알 가부시키가이샤 | 서지 업소버 |
CN102005754B (zh) * | 2010-12-11 | 2013-08-07 | 株洲普天中普防雷科技有限公司 | 一种双层金属间隙型电涌保护方法及电涌保护器 |
CN104392878B (zh) * | 2014-12-08 | 2017-01-25 | 深圳市威尔利实业有限公司 | 一种放电管及放电方法 |
CN108806905B (zh) * | 2018-06-29 | 2020-07-10 | 安徽诚意电气科技有限公司 | 一种具有灭弧功能的阀型避雷器 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3248600A (en) * | 1964-02-03 | 1966-04-26 | Mc Graw Edison Co | Lightning arrester with arc splitter |
JPH10247578A (ja) * | 1997-03-03 | 1998-09-14 | Okaya Electric Ind Co Ltd | 放電型サージ吸収素子の製造方法 |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2923849A (en) * | 1958-07-10 | 1960-02-02 | Gen Railway Signal Co | Lightning arrestor |
US3581154A (en) * | 1968-11-18 | 1971-05-25 | J Hebden Willox | Surge-deflecting cable terminator |
SE408982B (sv) * | 1977-11-11 | 1979-07-16 | Asea Ab | Gnistgapsanordning |
ES2207875T3 (es) * | 1994-10-07 | 2004-06-01 | PHOENIX CONTACT GMBH & CO. KG | Elemento de proteccion contra sobretension. |
DE19717802B4 (de) * | 1997-04-26 | 2009-09-17 | Dehn + Söhne GmbH + Co KG | Funkenstrecke |
DE20020771U1 (de) * | 2000-02-22 | 2001-02-15 | Dehn & Soehne | Druckfest gekapselte Funkenstreckenanordnung zum Ableiten von schädlichen Störgrößen durch Überspannung |
US20020167775A1 (en) * | 2001-04-03 | 2002-11-14 | Phoenix Contact Gmbh & Co. Kg | Overvoltage protection element and overvoltage protection means |
-
2005
- 2005-01-26 CN CNA2005800038915A patent/CN1918760A/zh active Pending
- 2005-01-26 WO PCT/JP2005/000991 patent/WO2005074084A1/ja active Application Filing
- 2005-01-26 US US10/588,075 patent/US20070183112A1/en not_active Abandoned
- 2005-01-26 KR KR1020067015604A patent/KR20060129367A/ko active IP Right Grant
- 2005-01-26 JP JP2005517451A patent/JPWO2005074084A1/ja active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3248600A (en) * | 1964-02-03 | 1966-04-26 | Mc Graw Edison Co | Lightning arrester with arc splitter |
JPH10247578A (ja) * | 1997-03-03 | 1998-09-14 | Okaya Electric Ind Co Ltd | 放電型サージ吸収素子の製造方法 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013186909A1 (ja) * | 2012-06-15 | 2013-12-19 | 合資会社シーエスディ | 火花ギャップアレスタ |
WO2013186951A1 (ja) * | 2012-06-15 | 2013-12-19 | 合資会社シーエスディ | 火花ギャップアレスタ |
JPWO2013186951A1 (ja) * | 2012-06-15 | 2016-02-01 | 合資会社シーエスディ | 火花ギャップアレスタ |
Also Published As
Publication number | Publication date |
---|---|
JPWO2005074084A1 (ja) | 2008-01-10 |
KR20060129367A (ko) | 2006-12-15 |
US20070183112A1 (en) | 2007-08-09 |
CN1918760A (zh) | 2007-02-21 |
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