JPH0354844B2 - - Google Patents
Info
- Publication number
- JPH0354844B2 JPH0354844B2 JP3907785A JP3907785A JPH0354844B2 JP H0354844 B2 JPH0354844 B2 JP H0354844B2 JP 3907785 A JP3907785 A JP 3907785A JP 3907785 A JP3907785 A JP 3907785A JP H0354844 B2 JPH0354844 B2 JP H0354844B2
- Authority
- JP
- Japan
- Prior art keywords
- melting point
- low melting
- point metal
- overvoltage limiting
- electrodes
- 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
- 238000002844 melting Methods 0.000 claims description 68
- 230000008018 melting Effects 0.000 claims description 64
- 229910052751 metal Inorganic materials 0.000 claims description 49
- 239000002184 metal Substances 0.000 claims description 49
- 150000002739 metals Chemical class 0.000 claims description 9
- 239000000155 melt Substances 0.000 claims description 4
- 238000007599 discharging Methods 0.000 claims description 2
- 230000006378 damage Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 4
- 230000002411 adverse Effects 0.000 description 3
- 239000011787 zinc oxide Substances 0.000 description 2
- 229910000711 U alloy Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009429 electrical wiring Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012634 fragment Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
Landscapes
- Thermistors And Varistors (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、過電圧制限素子の破壊による周辺
への悪影響を防止するようにした過電圧制限装置
に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an overvoltage limiting device that prevents damage to the surrounding area due to destruction of an overvoltage limiting element.
一般に、サイリスタを使用した高電圧の電力変
換装置においては、通常の動作電圧を考慮して素
子の直列個数が決定される。そして、散発的に印
加される雷インパルスや、開閉サージ等はアレス
タで所定の電圧に制限している。
Generally, in a high-voltage power converter using a thyristor, the number of elements connected in series is determined in consideration of the normal operating voltage. Sporadically applied lightning impulses, switching surges, etc. are limited to a predetermined voltage by arresters.
従来のものは、第３図に示すように、各サイリ
スタ素子T1，T2，T3に、アレスタA1，A2，A3
及びスナバー回路S1，S2，S3が並列に接続されて
いる。 In the conventional one, as shown in FIG. 3, each thyristor element T 1 , T 2 , T 3 has an arrester A 1 , A 2 , A 3
and snubber circuits S 1 , S 2 , and S 3 are connected in parallel.
この場合、各サイリスタ素子T1，T2，T3には
外部から雷インパルス等の過電圧が印加された場
合も、並列に接続されたアレスターA1，A2，A3
及びスナバー回路S1，S2，S3により、制限された
電圧VMしか印加されないため、各サイリスタ素
子T1，T2，T3は保護される。 In this case, even if an overvoltage such as a lightning impulse is applied from the outside to each thyristor element T 1 , T 2 , T 3 , the arrester A 1 , A 2 , A 3 connected in parallel
Since only a limited voltage V M is applied by the snubber circuits S 1 , S 2 , and S 3 , each thyristor element T 1 , T 2 , and T 3 is protected.
しかし、各サイリスタT1，T2，T3に導通指令
が出たとき、点弧回路の故障によつて、サイリス
タ素子T1のみが導通しなかつたとすると、サイ
リスタ素子T1を残した他のサイリスタ素子T2，
T3が導通し、サイリスタ素子T1と並列に接続さ
れたアレスターA1には、外部の回路条件で決定
される負荷電流が強制的に流れ、その端子電圧は
アレスターA1の電圧−電流特性によつて決定さ
れる値となる。 However, when a conduction command is issued to each thyristor T 1 , T 2 , T 3 , if only thyristor element T 1 fails to conduct due to a failure in the ignition circuit, the remaining thyristor element T 1 Thyristor element T 2 ,
When T 3 is conductive, a load current determined by the external circuit conditions is forced to flow through arrester A 1 connected in parallel with thyristor element T 1 , and its terminal voltage is determined by the voltage-current characteristics of arrester A 1 . The value is determined by .
通常、アレスタは負荷電流のような過大な電流
を長時間流す能力をもつていないので、過電圧制
限要素は最終的に破壊する。 Typically, the overvoltage limiting element will eventually fail because the arrester does not have the ability to carry excessive currents such as the load current for long periods of time.
その時、飛散した破片で周辺の部品を損傷した
り、持続的なアークの発生により電力変換装置内
に悪影響を与えることがあるので、第４図に示す
ように、あるいは特開昭59−37679号の発明のよ
うに過電圧制限要素が破壊したら、ただちにアレ
スタの両端を電気的に短絡するように構成された
ものが提案されている。 At that time, the scattered fragments may damage surrounding parts, and continuous arcing may adversely affect the inside of the power converter. An arrester has been proposed that is configured to electrically short-circuit both ends of the arrester immediately when the overvoltage limiting element breaks down, as in the invention of .
すなわち、第４図では、酸化亜鉛形アレスタな
どの過電圧制限要素１に半田などの低融点金属２
を当接させ、一対の電極３，４間に過電圧制限要
素１と低融点金属２とを電気的に直列接続し、ば
ね５で一方の電極３に押圧し、他方の電極４とは
シヤント６で接続し、溶融した低融点金属２で両
通電部３ａ，４ａが電気的に接続されるように、
対向した両通電部３ａ，４ａが低融点金属２の下
部に配置してある。絶縁性容器７は一対の電極
３，４を保持している。 That is, in FIG. 4, an overvoltage limiting element 1 such as a zinc oxide type arrester is connected to a low melting point metal 2 such as solder.
The overvoltage limiting element 1 and the low melting point metal 2 are electrically connected in series between the pair of electrodes 3 and 4, and the spring 5 presses one electrode 3, and the other electrode 4 is connected to the shunt 6. so that both current-carrying parts 3a and 4a are electrically connected by the molten low-melting point metal 2.
Both opposing current-carrying parts 3a and 4a are arranged below the low melting point metal 2. The insulating container 7 holds a pair of electrodes 3 and 4.
上記構成において、過電圧制限要素１に過大な
電流が流れる場合、電極３→過電圧制限要素１→
低融点金属２→シヤント６→電極４の回路を通
る。これによつて、過電圧制限要素１の破壊時に
は、アーク熱により低融点金属２が溶融して両通
電部３ａ，４ａ間に落下し、両電極３，４間が電
気的に接続される。 In the above configuration, when excessive current flows through overvoltage limiting element 1, electrode 3 → overvoltage limiting element 1 →
It passes through a circuit of low melting point metal 2 → shunt 6 → electrode 4. As a result, when the overvoltage limiting element 1 is destroyed, the low melting point metal 2 is melted by the arc heat and falls between the current carrying parts 3a and 4a, thereby electrically connecting the electrodes 3 and 4.
したがつて、過電圧制限要素１に流れていた電
流は、両通電部３ａ，４ａ間に落下した低融点金
属２を経由して流れるようになるので、過電圧制
限要素１の破壊による周辺への悪影響を除去でき
る。また、前記特開昭59−37679号の発明では、
上記第４図の構成における低融点金属２の部分が
他方の電極であり、低融点金属は１対の電極の間
の上方に保持されたものであるが、動作は第４図
のものと実質的に同一である。 Therefore, the current that was flowing through the overvoltage limiting element 1 will now flow through the low melting point metal 2 that has fallen between the two current-carrying parts 3a and 4a, so that the destruction of the overvoltage limiting element 1 will not have an adverse effect on the surrounding area. can be removed. Furthermore, in the invention of JP-A No. 59-37679,
The low melting point metal 2 part in the configuration shown in FIG. are essentially the same.
しかしながら、低融点金属２の溶融量が少ない
場合、低融点金属２によつて形成された短絡路
は、かなり高い抵抗値を有する。このため、その
後連続的に流れる負荷電流によつて短絡路が発熱
することになる。
However, when the melting amount of the low melting point metal 2 is small, the short circuit formed by the low melting point metal 2 has a considerably high resistance value. Therefore, the short circuit generates heat due to the load current that subsequently flows continuously.
実験結果によれば、短絡路の温度上昇は、低融
点金属２の融点近くまで達するケースがあること
が確認された。電圧制限要素１の通常のサージ処
理を考慮すると、低融点金属２の融点をあまり低
く設定することができないので、一般に短絡路の
温度上昇値は、最高130℃近くになる。 According to the experimental results, it was confirmed that there are cases in which the temperature rise in the short circuit reaches close to the melting point of the low melting point metal 2. Considering the normal surge handling of the voltage limiting element 1, the melting point of the low melting point metal 2 cannot be set too low, so the temperature rise value of the short circuit generally reaches a maximum of nearly 130°C.
このような温度上昇が、電力変換装置内のサイ
リスタ素子T1，T2，T3や過電圧制限要素A2，A3
やスナバー回路S1，S2，S3用部品等に悪影響を与
えることは明らかである。 Such a temperature rise may cause damage to the thyristor elements T 1 , T 2 , T 3 and overvoltage limiting elements A 2 , A 3 in the power converter.
It is clear that this will have an adverse effect on the components of the snubber circuits S 1 , S 2 , S 3 , etc.
従来の以上のような過電圧制限装置において、
抵抗値の小さな短絡路を形成するためには、まず
第１に、大量の低融点金属２を瞬間的に溶融させ
る必要があるが、負荷電流が小さな場合は困難で
ある。 In the conventional overvoltage limiting device as described above,
In order to form a short circuit with a small resistance value, first of all, it is necessary to instantaneously melt a large amount of low melting point metal 2, but this is difficult when the load current is small.
即ち、過電圧制限要素１の負荷電流による温度
上昇の過程で、たとえ微量であつても、溶融した
低融点金属２によつて短絡路が形成された瞬間
に、過電圧制限要素１の温度上昇が停止し、それ
以後低融点金属２の溶融がとまるからである。 That is, in the process of temperature rise due to the load current of the overvoltage limiting element 1, the temperature rise of the overvoltage limiting element 1 stops at the moment a short circuit is formed by the melted low melting point metal 2, even if it is a small amount. This is because the low melting point metal 2 stops melting after that.
この発明の目的は上記のような問題点を解消す
るために、負荷電流が小さな場合でも、抵抗値の
きわめて小さな短絡路を形成する過電圧制限装置
を提供するものである。 SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an object of the present invention is to provide an overvoltage limiting device that forms a short circuit with extremely low resistance even when the load current is small.
この発明に係る過電圧制限装置は、過電圧制限
要素を挾持する一対の電極に、融点の異なる第
１、第２の低融点金属を埋込み、融点の高い第１
の低融点金属で融点の低い第２の低融点金属を覆
うようにしたものである。
In the overvoltage limiting device according to the present invention, first and second low melting point metals having different melting points are embedded in a pair of electrodes that sandwich an overvoltage limiting element, and the first and second low melting point metals have different melting points.
A second low melting point metal having a low melting point is covered with a second low melting point metal having a low melting point.
この発明における過電圧制限装置は、過電圧制
限要素の破壊時に第１の低融点金属を溶融させて
一対の電極間を短絡させ、負荷電流による短絡路
の温度上昇によつて、第２の低融点金属を溶融さ
せて短絡路の抵抗値を下げる。
The overvoltage limiting device of the present invention melts the first low melting point metal to short-circuit between the pair of electrodes when the overvoltage limiting element breaks down, and the second low melting point metal is melted by the temperature rise of the short circuit path caused by the load current. melts to lower the resistance of the short circuit.
以下この発明の一実施例を図について説明す
る。第１図はこの発明に係る過電圧制限装置の一
実施例を示す側断面図であり、第２図は第１図の
部分の拡大図である。第１図及び第２図におい
て、過電圧制限要素１は例えば酸化亜鉛素子で構
成されている。一対の電極９，１０は過電圧制限
要素１を挾持するもので、それぞれ相対するよう
に第１、第２の低融点金属１１，１２を埋込む円
形に設けられた溝９ａ，１０ａと、溝９ａ，１０
ａの外周に設けられ第１、第２の低融点金属１
１，１２の溶融により短絡路を形成する通電部９
ｂ，１０ｂと、溝９ａ，１０ａ内から外周表面に
貫通して設けられ第１、第２の低融点金属１１，
１２の溶融時に発生するガスを外部に排出するガ
ス流通口９ｃ，１０ｃとを備えている。第１、第
２の低融点金属１１，１２は例えばＵアロイ（大
阪アサヒメタル工場製の商品の名称）である。同
商品の中には融点が47℃〜183℃の各種のものが
市販されている。第１の低融点金属１１として
は、例えば過電圧制限要素１の通常のサージ処理
時の最高許容温度以上の高い融点に設定されてい
る。第２の低融点金属１２としては短絡路が形成
された後の負荷電流通電時の最高許容温度の融点
に設定されており、この融点は第１の低融点金属
のそれより低い。第１の低融点金属１１は第２の
低融点金属１２を覆うようにされ、両者が二層に
溝９ａ，１０ａ内に埋込まれている。一対の主電
極３Ａ，４Ａと例えば筒状の絶縁体７Ａとで容器
を形成し、一対の電極９，１０に挾持された過電
圧制限要素１を収納している。ばね５Ａは電極１
０と主電極４Ａ間に装着され、電極９を主電極３
Ａに圧接している。シヤント６Ａは電極１０と主
電極４Ａとを接続するものである。
An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing an embodiment of an overvoltage limiting device according to the present invention, and FIG. 2 is an enlarged view of the portion shown in FIG. 1. In FIGS. 1 and 2, the overvoltage limiting element 1 is composed of, for example, a zinc oxide element. A pair of electrodes 9 and 10 sandwich the overvoltage limiting element 1, and have circular grooves 9a and 10a in which first and second low-melting point metals 11 and 12 are embedded, facing each other, and a groove 9a. ,10
First and second low melting point metals 1 provided on the outer periphery of a
A current-carrying part 9 that forms a short circuit path by melting 1 and 12.
b, 10b, and first and second low melting point metals 11, which are provided to penetrate from inside the grooves 9a, 10a to the outer peripheral surface.
Gas flow ports 9c and 10c are provided for discharging gas generated during melting of 12 to the outside. The first and second low melting point metals 11 and 12 are, for example, U alloy (a product name manufactured by Osaka Asahi Metal Factory). Various products with melting points of 47°C to 183°C are commercially available. The first low melting point metal 11 is set to have a high melting point, for example, higher than the maximum allowable temperature of the overvoltage limiting element 1 during normal surge processing. The melting point of the second low melting point metal 12 is set to the maximum allowable temperature when the load current is applied after the short circuit is formed, and this melting point is lower than that of the first low melting point metal. The first low melting point metal 11 is arranged to cover the second low melting point metal 12, and both are embedded in the grooves 9a and 10a in two layers. A container is formed by a pair of main electrodes 3A, 4A and, for example, a cylindrical insulator 7A, and houses an overvoltage limiting element 1 held between a pair of electrodes 9, 10. Spring 5A is electrode 1
0 and main electrode 4A, and connects electrode 9 to main electrode 3A.
It is in pressure contact with A. The shunt 6A connects the electrode 10 and the main electrode 4A.
次に動作を説明する。過電圧制限要素１に所定
以上の過大な電流が流れると、過電圧制限要素１
が破壊し、アークが発生する。そのアークは溝９
ａ，１０ａ内の表面の第１の低融点金属１１を溶
融させて、一対の電極９，１０の下部の通電部９
ｂ，１０ｂ間に短絡路を形成する。第１の低融点
金属１１の溶融量が少なく短絡路の抵抗値の高い
場合は、負荷電流によつて短絡路の温度は上昇し
続けるが、その温度が溝９ａ，１０ａ内の内側の
第２の低融点金属１２の融点に達した時、第２の
低融点金属１２は液状化し、第１の低融点金属１
１の１部が溶融すると溶融部より第２の低融点金
属１２が流出する。 Next, the operation will be explained. When an excessive current exceeding a predetermined value flows through the overvoltage limiting element 1, the overvoltage limiting element 1
is destroyed and an arc is generated. That arc is groove 9
The first low-melting point metal 11 on the surface inside the electrodes 9 and 10a is melted to form the current-carrying portion 9 at the bottom of the pair of electrodes 9 and 10.
A short circuit is formed between b and 10b. When the amount of melting of the first low melting point metal 11 is small and the resistance value of the short circuit path is high, the temperature of the short circuit path continues to rise due to the load current, When the melting point of the low melting point metal 12 is reached, the second low melting point metal 12 liquefies and the first low melting point metal 1
When a part of the metal 1 melts, the second low melting point metal 12 flows out from the melted part.
この時、一対の電極９，１０の上部に設けられ
たガス流通口９ｃ，１０ｃから、第２の低融点金
属１２の溶融時に発生するガスが、外部に排出さ
れる。このため、第２の低融点金属１２の流出圧
力は、自重によつて与えられる。従つて、短絡路
の最高温度は、最悪、第２の低融点金属１２の融
点に抑制される。 At this time, gas generated when the second low melting point metal 12 is melted is discharged to the outside from gas flow ports 9c and 10c provided at the top of the pair of electrodes 9 and 10. Therefore, the outflow pressure of the second low melting point metal 12 is given by its own weight. Therefore, in the worst case, the maximum temperature of the short circuit is suppressed to the melting point of the second low melting point metal 12.
以上のように、この発明によれば、短絡路が最
終的にサージ処理時の最高許容温度以下の融点を
有する第２の低融点金属によつて形成されるため
に、短絡路作時の第１の低融点金属皮膜の溶融量
がわずかであつても、短絡路の温度上昇値をきわ
めて低くすることができる効果がある。
As described above, according to the present invention, since the short circuit is finally formed of the second low melting point metal having a melting point lower than the maximum allowable temperature during surge processing, the short circuit is Even if the amount of melting of the low melting point metal film No. 1 is small, there is an effect that the temperature rise value of the short circuit can be made extremely low.
第１図はこの発明に係る過電圧制限装置の一実
施例を示す側断面図、第２図は第１図の部分の
拡大図、第３図は一般的な電力変換装置を示す電
気結線図、第４図は従来の過電圧制限装置を示す
側断面図である。
図において、１は過電圧制限要素、９，１０は
一対の電極、９ｂ，１０ｂは通電部、９ｃ，１０
ｃはガス流通口、１１，１２は第１、第２の低融
点金属である。なお、各図中同一符号は同一また
は相当部分を示す。
FIG. 1 is a side sectional view showing an embodiment of the overvoltage limiting device according to the present invention, FIG. 2 is an enlarged view of the portion shown in FIG. 1, and FIG. 3 is an electrical wiring diagram showing a general power converter. FIG. 4 is a side sectional view showing a conventional overvoltage limiting device. In the figure, 1 is an overvoltage limiting element, 9 and 10 are a pair of electrodes, 9b and 10b are current carrying parts, and 9c and 10
c is a gas flow port, and 11 and 12 are first and second low melting point metals. Note that the same reference numerals in each figure indicate the same or corresponding parts.
Claims (1)
前記一対の電極に二層に埋込まれ前記過電圧制限
要素の破壊時に溶融して前記一対の電極間を短絡
する第１、第２の低融点金属、第１の低融点金属
に覆われて設けられ第１の低融点金属より融点の
低い第２の低融点金属、を具備することを特徴と
する過電圧制限装置。 ２ 一対の電極は、第１、第２の低融点金属の溶
融時に短絡する通電部を備えている特許請求の範
囲第１項記載の過電圧制限装置。 ３ 一対の電極は、第１、第２の低融点金属の溶
融時に発生するガスを外部に排出するガス流通口
を備えている特許請求の範囲第１項または第２項
記載の過電圧制限装置。[Scope of Claims] 1. A pair of electrodes that sandwich the overvoltage limiting element, and a first electrode that is embedded in the pair of electrodes in two layers and melts when the overvoltage limiting element is broken to short-circuit the pair of electrodes. An overvoltage limiting device comprising: a second low melting point metal; a second low melting point metal that is covered with the first low melting point metal and has a melting point lower than that of the first low melting point metal. 2. The overvoltage limiting device according to claim 1, wherein the pair of electrodes includes a current-carrying part that shorts when the first and second low-melting point metals are melted. 3. The overvoltage limiting device according to claim 1 or 2, wherein the pair of electrodes is provided with a gas flow port for discharging gas generated when the first and second low melting point metals are melted to the outside.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3907785A JPS61198701A (en) | 1985-02-28 | 1985-02-28 | Overvoltage controller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3907785A JPS61198701A (en) | 1985-02-28 | 1985-02-28 | Overvoltage controller |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61198701A JPS61198701A (en) | 1986-09-03 |
| JPH0354844B2 true JPH0354844B2 (en) | 1991-08-21 |
Family
ID=12543046
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3907785A Granted JPS61198701A (en) | 1985-02-28 | 1985-02-28 | Overvoltage controller |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61198701A (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7433169B2 (en) * | 2005-12-15 | 2008-10-07 | Raycap Corporation | Overvoltage protection devices including wafer of varistor material |
| US8743525B2 (en) | 2012-06-19 | 2014-06-03 | Raycap Intellectual Property, Ltd | Overvoltage protection devices including wafer of varistor material |
| US9906017B2 (en) | 2014-06-03 | 2018-02-27 | Ripd Research And Ip Development Ltd. | Modular overvoltage protection units |
| US10319545B2 (en) | 2016-11-30 | 2019-06-11 | Iskra Za{hacek over (s)}{hacek over (c)}ite d.o.o. | Surge protective device modules and DIN rail device systems including same |
| US10707678B2 (en) | 2016-12-23 | 2020-07-07 | Ripd Research And Ip Development Ltd. | Overvoltage protection device including multiple varistor wafers |
| US10447026B2 (en) | 2016-12-23 | 2019-10-15 | Ripd Ip Development Ltd | Devices for active overvoltage protection |
| US10340110B2 (en) | 2017-05-12 | 2019-07-02 | Raycap IP Development Ltd | Surge protective device modules including integral thermal disconnect mechanisms and methods including same |
| US10685767B2 (en) | 2017-09-14 | 2020-06-16 | Raycap IP Development Ltd | Surge protective device modules and systems including same |
| US11223200B2 (en) | 2018-07-26 | 2022-01-11 | Ripd Ip Development Ltd | Surge protective devices, circuits, modules and systems including same |
| US11862967B2 (en) | 2021-09-13 | 2024-01-02 | Raycap, S.A. | Surge protective device assembly modules |
| US11723145B2 (en) | 2021-09-20 | 2023-08-08 | Raycap IP Development Ltd | PCB-mountable surge protective device modules and SPD circuit systems and methods including same |
| US11990745B2 (en) | 2022-01-12 | 2024-05-21 | Raycap IP Development Ltd | Methods and systems for remote monitoring of surge protective devices |
-
1985
- 1985-02-28 JP JP3907785A patent/JPS61198701A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61198701A (en) | 1986-09-03 |
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