JPH0773406B2 - Surge absorption circuit for DC power supply - Google Patents
Surge absorption circuit for DC power supplyInfo
- Publication number
- JPH0773406B2 JPH0773406B2 JP2195193A JP2195193A JPH0773406B2 JP H0773406 B2 JPH0773406 B2 JP H0773406B2 JP 2195193 A JP2195193 A JP 2195193A JP 2195193 A JP2195193 A JP 2195193A JP H0773406 B2 JPH0773406 B2 JP H0773406B2
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- power supply
- surge
- relay
- surge absorbing
- 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 - Fee Related
Links
- 238000010521 absorption reaction Methods 0.000 title description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 40
- 239000011787 zinc oxide Substances 0.000 claims description 20
- 238000010586 diagram Methods 0.000 description 6
- 230000006866 deterioration Effects 0.000 description 3
- 230000007423 decrease Effects 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 230000003111 delayed effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
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- Emergency Protection Circuit Devices (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、直流電源を使用する通
信機器等の入力側に接続するサージ吸収回路に関し、特
に、回路構成部品の破損及び劣化を防止するとともに、
回路構成が簡潔で信頼性の高い直流電源用サージ吸収回
路に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surge absorbing circuit connected to an input side of a communication device or the like which uses a DC power source, and more particularly, to prevent damage and deterioration of circuit components,
The present invention relates to a surge absorbing circuit for a DC power supply, which has a simple circuit configuration and high reliability.
【０００２】[0002]
【従来の技術】従来の直流電源用サージ吸収回路とし
て、例えば、図３に示すようなものがある。図３は、直
流電源用サージ吸収回路の最も基本的なものであり、負
荷７の入力側回路に避雷管１と酸化亜鉛バリスタ２を並
列に接続した構成となっている。一般的には、避雷管１
はサージエネルギー耐量が大きく応答速度が遅いという
特性を有し、また、酸化亜鉛バリスタ２はサージエネル
ギー耐量が小さく応答速度が速いという特性を有する。
図３の直流電源用サージ吸収回路は、これら避雷管１と
酸化亜鉛バリスタ２の特性を利用したものであり、速度
の速い雷サージは酸化バリスタ２に吸収させ、エネルギ
ー耐量を必要とする波尾長の長い雷サージは避雷管１に
吸収させている。しかし、図３の直流電源用サージ吸収
回路では、避雷管１の内部放電による雷サージ消滅後
に、直流電源からの電流が避雷管１に流れ込むという続
流の問題があった。2. Description of the Related Art As a conventional surge absorbing circuit for a DC power source, there is, for example, one shown in FIG. FIG. 3 shows the most basic type of surge absorbing circuit for a DC power supply, which has a structure in which an arrester 1 and a zinc oxide varistor 2 are connected in parallel to an input side circuit of a load 7. Generally, lightning arrester 1
Has a large surge energy resistance and a slow response speed, and the zinc oxide varistor 2 has a small surge energy resistance and a fast response speed.
The surge absorbing circuit for the DC power supply of FIG. 3 utilizes the characteristics of the lightning arrester 1 and the zinc oxide varistor 2, and the lightning surge having a high speed is absorbed by the oxide varistor 2 and the wave tail length which requires energy resistance. The lightning arrester 1 absorbs a long lightning surge. However, the surge absorbing circuit for the DC power supply of FIG. 3 has a problem of a follow-up flow in which the current from the DC power supply flows into the lightning arrester 1 after the lightning surge disappears due to the internal discharge of the lightning arrester 1.
【０００３】そこで、この続流を防止するため、図４〜
６に示すような直流電源用サージ吸収回路が提案されて
いる。図４及び図５に示す直流電源用サージ吸収回路
は、それぞれ避雷管１より入力側に電流制限用抵抗８を
直列接続してある。この電流制限用抵抗８は、雷サージ
の消滅後、直流電源から避雷管１に流れる電流を制限
し、続流を防止する。Therefore, in order to prevent this continuous flow, FIG.
A surge absorbing circuit for a DC power supply as shown in 6 has been proposed. In the surge absorbing circuits for DC power supply shown in FIGS. 4 and 5, a current limiting resistor 8 is connected in series from the lightning arrester 1 to the input side. The current limiting resistor 8 limits the current flowing from the DC power source to the lightning arrester 1 after the lightning surge disappears, and prevents a follow-up current.
【０００４】また、図６に示す直流電源用サージ吸収回
路は、避雷管１に酸化亜鉛バリスタ９を直列接続してあ
る。このような直流電源用サージ吸収回路によれば、雷
サージ電圧により避雷管１が放電すると、このときの放
電電流により酸化亜鉛バリスタ９の両端に電圧が発生す
る。これによって、雷サージ電圧の消滅後、避雷管１に
印加される電圧は小さく制限され、続流が防止される。In the surge absorbing circuit for a DC power source shown in FIG. 6, a zinc oxide varistor 9 is connected in series to the arrester 1. According to such a surge absorbing circuit for a DC power supply, when the lightning arrester 1 is discharged by a lightning surge voltage, a voltage is generated across the zinc oxide varistor 9 by the discharge current at this time. As a result, after the lightning surge voltage disappears, the voltage applied to the lightning arrester 1 is limited to a small value, and the follow current is prevented.
【０００５】なお、他の直流電源用サージ吸収回路とし
て、特６３−８１７１４号の公報において、直流電源と
負荷との間に、筒形ヒューズ，開閉器の接点及び過電流
継電器を直列接続してなる第一の回路と、コイル励磁用
電源，上記筒形ヒューズの溶断時に開放するインターロ
ック接点，上記開閉器のコイル及び過電流継電器の接点
を直列接続してなり、上記過電流継電器の動作時に、当
該継電器の常開接点によって、上記開閉器のコイルの励
磁状態を上記インターロック接点が開放するまでの間保
持する第二の回路とを備えた構成の直流遮断回路が提案
されている。この直流遮断回路は、大電流が印加された
場合に、過電流継電器の動作により開閉器が投入状態を
保持して電流遮断を行なわないようにするとともに、ヒ
ューズの溶断と同時に接点を開いてヒューズ溶断時のア
ークによる続流を遮断する。As another surge absorbing circuit for DC power source, in Japanese Patent Publication No. 63-81714, a cylindrical fuse, a switch contact and an overcurrent relay are connected in series between a DC power source and a load. The following circuit is connected in series with the coil exciting power supply, the interlock contact that opens when the cylindrical fuse is blown, the switch coil and the overcurrent relay contact, and A DC cutoff circuit having a configuration in which a normally open contact of the relay holds a magnetized state of a coil of the switch until the interlock contact is opened has been proposed. This DC cutoff circuit prevents the current from being cut off by keeping the switch in the closed state by the operation of the overcurrent relay when a large current is applied, and at the same time the fuse is blown, the contacts are opened and the fuse is opened. Shuts off the subsequent flow due to the arc during fusing.
【０００６】[0006]
【発明が解決しようとする課題】しかしながら、上述し
た図４及び図５に示す直流電源用サージ吸収回路は、直
流電源の入力側に電流制限抵抗８を接続するために、電
源効率が低下してしまうという問題点があった。また、
図５に示す直流電源用サージ吸収回路では、雷サージに
よって避雷管１の放電電流により、電流制限用抵抗８の
両端に大きな電圧が発生し、この電圧及び雷サージエネ
ルギーの一部が酸化亜鉛バリスタ２に加わるため酸化亜
鉛バリスタ２が劣化しやすいという問題点があった。However, in the surge absorbing circuit for the DC power source shown in FIGS. 4 and 5, the current limiting resistor 8 is connected to the input side of the DC power source, so that the power source efficiency is lowered. There was a problem that it would end up. Also,
In the surge absorbing circuit for the DC power supply shown in FIG. 5, a large voltage is generated across the current limiting resistor 8 due to the discharge current of the lightning arrester 1 due to a lightning surge, and this voltage and a part of the lightning surge energy are zinc oxide varistor. In addition, there is a problem that the zinc oxide varistor 2 is likely to deteriorate because
【０００７】さらに、図６に示す直流電源用サージ吸収
回路では、避雷管１が放電すると酸化亜鉛バリスタ９に
サージ電流が流れるため、波尾長の長い雷サージが侵入
すると、この酸化亜鉛バリスタ９が劣化してしまうとい
った問題点があった。Further, in the surge absorbing circuit for the DC power supply shown in FIG. 6, when the lightning arrester 1 discharges, a surge current flows through the zinc oxide varistor 9. Therefore, when a lightning surge with a long wave tail enters, the zinc oxide varistor 9 There was a problem that it deteriorated.
【０００８】またさらに、特開昭６３−８１７１４号の
公報に記載された直流遮断回路は、回路を構成する部品
が多く、回路構成が煩雑になりコスト高あるいは信頼性
の低下をまねくといった問題があった。Furthermore, the DC cutoff circuit described in Japanese Patent Laid-Open No. 63-81714 has many problems that the circuit configuration is complicated and the circuit configuration becomes complicated, resulting in high cost and reduced reliability. there were.
【０００９】本発明は、上記問題点にかんがみてなされ
たものであり、回路構成部品の劣化，破損をともなわず
に続流の発生を防止し、しかも簡潔な回路構成で信頼性
の高い直流電源用サージ吸収回路の提供を目的とする。The present invention has been made in view of the above problems, and prevents the occurrence of a follow-up current without deterioration or damage of circuit components, and has a simple circuit structure and high reliability. The purpose of the present invention is to provide a surge absorption circuit.
【００１０】上記目的を達成するために、本発明の直流
電源用サージ吸収回路は、入力側回路に避雷管と酸化亜
鉛バリスタを並列に接続した直流電源用サージ吸収回路
において、この入力側回路に直列に接続したインダクタ
ンスと、このインダクタンスに並列に接続したリレー
と、前記避雷管に直列に接続した前記リレーの接点とを
備えた構成となっており、好ましくは、前記リレーと並
列に酸化亜鉛バリスタを接続した構成としてある。In order to achieve the above object, the surge absorbing circuit for DC power supply of the present invention is a surge absorbing circuit for DC power supply in which a lightning arrester and a zinc oxide varistor are connected in parallel to the input side circuit. Inductance connected in series, a relay connected in parallel to this inductance, and a contact of the relay connected in series to the arrester, preferably, a zinc oxide varistor in parallel with the relay. Are connected.
【００１１】[0011]
【作用】上記構成からなる本発明の直流電源用サージ吸
収回路によれば、雷サージの侵入があった場合、インダ
クタンスの両端に雷サージ電流の時間微分に比例した誘
導起電力（ＶL ＝−Ｌ・ｄｉ／ｄｔ）が発生し、リレー
が励磁する。その後、数ｍｓ〜数十ｍｓ遅れてリレー接
点がＯＦＦ状態となり、避雷管と回路との接続を断つ。
すなわち、避雷管は、雷サージの侵入があった直後か
ら、リレー接点がＯＦＦ状態となる間だけ放電を行な
う。According to the surge absorbing circuit for a DC power supply of the present invention having the above-described structure, when a lightning surge enters, an induced electromotive force ( VL =-) proportional to the time derivative of the lightning surge current across the inductance. L · di / dt) occurs and the relay is excited. After that, the relay contact is turned off after a delay of several ms to several tens of ms, and the arrester and the circuit are disconnected.
That is, the lightning arrester discharges only immediately after the lightning surge invades and while the relay contact is in the OFF state.
【００１２】[0012]
【実施例】以下、本発明の直流電源用サージ吸収回路の
実施例について図面を参照しつつ説明する。図１は本実
施例に係る直流電源用サージ吸収回路を示す回路図であ
る。また、本実施例において、従来例と同様の部分につ
いては同一番号を付して詳細な説明は省略する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a surge absorbing circuit for a DC power supply of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram showing a surge absorbing circuit for a DC power source according to this embodiment. Further, in the present embodiment, the same parts as those of the conventional example are designated by the same reference numerals and detailed description thereof will be omitted.
【００１３】図１において、３はインダクタンスであ
り、入力側回路所避雷管１と酸化亜鉛バリスタ２の間に
直列に接続してある。このインダクタンス３は、雷サー
ジの侵入等によって、両端に誘導起電力（ＶL ＝−Ｌ・
ｄｉ／ｄｔ）を発生して、後述するリレー４を動作させ
る。リレー４は、インダクタンス３に並列接続してあ
り、通常はＯＦＦ状態となっている。このリレー４は、
インダクタンス３が発生する誘導起電力によって作動す
る。５は酸化亜鉛バリスタであり、リレー４に並列接続
してある。この酸化亜鉛バリスタ５は、雷サージが回路
に侵入した場合、この雷サージからリレー４を保護す
る。６はリレー４の接点であり、避雷管１に直列接続し
てある。In FIG. 1, reference numeral 3 denotes an inductance, which is connected in series between the arrester 1 at the input side circuit and the zinc oxide varistor 2. This inductance 3 is induced electromotive force ( VL = -L.
(di / dt) is generated and the relay 4 described later is operated. The relay 4 is connected in parallel with the inductance 3 and is normally in the OFF state. This relay 4
It operates by the induced electromotive force generated by the inductance 3. A zinc oxide varistor 5 is connected in parallel with the relay 4. This zinc oxide varistor 5 protects the relay 4 from a lightning surge if it enters the circuit. Reference numeral 6 is a contact of the relay 4, which is connected to the lightning arrester 1 in series.
【００１４】次に、上述した構成からなる本実施例の直
流電源用サージ吸収回路の動作について、図１及び図２
を参照しつつ説明する。これら図面において、まず、雷
サージの侵入がない場合は、インダクタンス３の両端に
誘導起電力が発生しないので、リレー４は動作しない。
したがって、リレー４の接点５はＯＮ状態を保ち、避雷
管１も回路との接続を保つ。Next, the operation of the surge absorbing circuit for the DC power source of the present embodiment having the above-mentioned configuration will be described with reference to FIGS.
Will be described with reference to. In these drawings, first, if there is no intrusion of lightning surge, the induced electromotive force is not generated at both ends of the inductance 3, so that the relay 4 does not operate.
Therefore, the contact 5 of the relay 4 is kept in the ON state, and the arrester 1 is also kept connected to the circuit.
【００１５】一方、雷サージの侵入があった場合は、イ
ンダクタンス３の両端に、雷サージ電流の時間微分に比
例した誘導起電力が発生する。そして、この誘導起電力
がリレー４の感動電圧まで上昇したとき、リレー４が作
動する。これによって、接点５がＯＦＦ状態となる。こ
こで、図２に示すように、通常、リレーの接点はリレー
の作動開始から数ｍｓ〜数十ｍｓ遅れて動作するため、
接点５は、リレー４の作動開始からｔ1 だけ遅れてＯＦ
Ｆ状態となる。したがて、接点５は雷サージが侵入した
直後、ｔ1 だけＯＮ状態を保ち、避雷管１にｔ1 の間放
電を行なわせる。そして、ｔ1 経過後、接点５はＯＦＦ
状態となって、避雷管１と回路との接続を断ち、避雷管
１の放電を停止させる。これによって、避雷管１を流れ
続ける続流は遮断される。その後、サージ電圧が減少す
るにつれて、誘導起電力も低下し、リレー４の励磁が解
かれる。これによって、接点５はリレー４の励磁終了か
らｔ2 だけ遅れて再びＯＮ状態に戻る。On the other hand, when a lightning surge enters, an induced electromotive force proportional to the time derivative of the lightning surge current is generated at both ends of the inductance 3. Then, when this induced electromotive force rises to the touching voltage of the relay 4, the relay 4 operates. As a result, the contact 5 is turned off. Here, as shown in FIG. 2, normally, the contact of the relay operates after a delay of several ms to several tens of ms from the start of operation of the relay.
The contact 5 is delayed by t 1 from the start of the operation of the relay 4 and becomes OF
It becomes the F state. Therefore, the contact 5 is kept in the ON state for t 1 immediately after the lightning surge enters, and the arrester 1 is caused to discharge for t 1 . Then, after the lapse of t 1 , the contact 5 is turned off.
In this state, the arrester 1 and the circuit are disconnected from each other, and the discharge of the arrester 1 is stopped. As a result, the continuous flow that continues to flow through the arrester 1 is cut off. After that, as the surge voltage decreases, the induced electromotive force also decreases, and the excitation of the relay 4 is released. As a result, the contact 5 returns to the ON state again after a delay of t 2 from the end of the excitation of the relay 4.
【００１６】このような、本実施例の直流電源用サージ
吸収回路によれば、避雷管１の放電後、リレー４の接点
がＯＦＦ状態となるので、避雷管１の放電後に発生する
続流は回路から遮断される。According to the surge absorbing circuit for the DC power supply of this embodiment, the contact of the relay 4 is turned off after the lightning arrester 1 is discharged, so that the continuous current generated after the lightning arrester 1 is discharged. Disconnected from the circuit.
【００１７】なお、本発明の直流電源用サージ吸収回路
は、上述した実施例に限定されるものではない。例え
ば、リレー４を保護するための酸化亜鉛バリスタ５を省
略したとしても、本発明の直流電源用サージ吸収回路が
奏する効果は変わらない。The surge absorbing circuit for DC power supply of the present invention is not limited to the above-mentioned embodiment. For example, even if the zinc oxide varistor 5 for protecting the relay 4 is omitted, the effect of the surge absorbing circuit for the DC power supply of the present invention does not change.
【００１８】[0018]
【発明の効果】以上説明したように、本発明の直流電源
用サージ吸収回路は、避雷管の放電後、リレー接点がＯ
ＦＦ状態となって、避雷管と回路の接続を断ち、続流の
発生を防止しているので、酸化亜鉛バリスタ等の回路構
成部品に大きな電圧やサージ電流が加わらず、回路構成
部品の劣化，破損を確実に防止できる。また、本発明の
直流電源用サージ吸収回路は、構成が簡潔なので、コス
ト高をまねくことなく、さらに回路の信頼性も向上す
る。As described above, in the surge absorbing circuit for the DC power supply of the present invention, the relay contact is turned ON after the discharge arrester is discharged.
In the FF state, the circuit between the arrester and the circuit is cut off to prevent the generation of a follow-up current. Therefore, a large voltage or surge current is not applied to the circuit component parts such as the zinc oxide varistor, and the circuit component deterioration, You can surely prevent damage. Further, the surge absorbing circuit for a DC power supply of the present invention has a simple structure, so that the cost is not increased and the reliability of the circuit is further improved.
【図１】本発明の直流電源用サージ吸収回路の実施例を
示す回路図である。FIG. 1 is a circuit diagram showing an embodiment of a surge absorbing circuit for a DC power supply of the present invention.
【図２】図１の直流電源用サージ吸収回路の動作を示す
タイミングチャート図である。FIG. 2 is a timing chart showing the operation of the DC power supply surge absorbing circuit of FIG.
【図３】第一従来例に係る直流電源用サージ吸収回路を
示す回路図である。FIG. 3 is a circuit diagram showing a surge absorbing circuit for a DC power supply according to a first conventional example.
【図４】第二従来例に係る直流電源用サージ吸収回路を
示す回路図である。FIG. 4 is a circuit diagram showing a surge absorbing circuit for a DC power source according to a second conventional example.
【図５】第三従来例に係る直流電源用サージ吸収回路を
示す回路図である。FIG. 5 is a circuit diagram showing a surge absorbing circuit for a DC power source according to a third conventional example.
【図６】第四従来例に係る直流電源用サージ吸収回路を
示す回路図である。FIG. 6 is a circuit diagram showing a surge absorbing circuit for a DC power source according to a fourth conventional example.
１…避雷管 ２…酸化亜鉛バリスタ ３…インダクタンス ４…リレー ５…酸化亜鉛バリスタ ６…接点 ７…負荷 1 ... Lightning arrester 2 ... Zinc oxide varistor 3 ... Inductance 4 ... Relay 5 ... Zinc oxide varistor 6 ... Contact 7 ... Load
Claims (2)
を並列に接続した直流電源用サージ吸収回路において、 この入力側回路に直列に接続したインダクタンスと、 このインダクタンスに並列に接続したリレーと、 前記避雷管に直列に接続した前記リレーの接点とを備え
た直流電源用サージ吸収回路。1. In a surge absorbing circuit for a DC power supply in which an arrester and a zinc oxide varistor are connected in parallel to an input side circuit, an inductance connected in series to this input side circuit, and a relay connected in parallel to this inductance, A surge absorbing circuit for a DC power supply, comprising a contact of the relay connected in series to the lightning arrester.
接続した請求項１記載の直流電源用サージ吸収回路。2. The surge absorbing circuit for a DC power supply according to claim 1, wherein a zinc oxide varistor is connected in parallel with the relay.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2195193A JPH0773406B2 (en) | 1993-01-14 | 1993-01-14 | Surge absorption circuit for DC power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2195193A JPH0773406B2 (en) | 1993-01-14 | 1993-01-14 | Surge absorption circuit for DC power supply |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06217455A JPH06217455A (en) | 1994-08-05 |
| JPH0773406B2 true JPH0773406B2 (en) | 1995-08-02 |
Family
ID=12069376
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2195193A Expired - Fee Related JPH0773406B2 (en) | 1993-01-14 | 1993-01-14 | Surge absorption circuit for DC power supply |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0773406B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100247320B1 (en) * | 1997-08-12 | 2000-03-15 | 정명세 | Lightning arrester for signal lamp output line of traffic signal controller |
| KR100332341B1 (en) * | 1999-03-12 | 2002-04-12 | 한영수 | Arrester for protecting a power source |
| JP6296409B1 (en) * | 2017-10-26 | 2018-03-20 | 株式会社コンド電機 | Surge protection device |
| KR102869162B1 (en) * | 2024-04-22 | 2025-10-15 | 경상국립대학교산학협력단 | DC circuit breaker with dual MOV |
-
1993
- 1993-01-14 JP JP2195193A patent/JPH0773406B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06217455A (en) | 1994-08-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |