JP2009206066A

JP2009206066A - Hybrid dc relay

Info

Publication number: JP2009206066A
Application number: JP2008079087A
Authority: JP
Inventors: Kenji Tanabe; 賢治田邊; Akira Sugawara; 晃菅原
Original assignee: Daito Communication Apparatus Co Ltd; Niigata University NUC
Current assignee: Daito Communication Apparatus Co Ltd; Niigata University NUC
Priority date: 2008-02-27
Filing date: 2008-02-27
Publication date: 2009-09-10

Abstract

<P>PROBLEM TO BE SOLVED: To provide a DC relay performing repetitive motions in a compact size in a simple structure and attaining a high voltage and large current. <P>SOLUTION: An inverted circuit is arranged in parallel with a primary contact in a DC circuit, a break of the primary contact is carried out, and circuit current is inverted in the inverted circuit using a MOS-FET as a formation element. After limiting the current, extension of contact capacity is provided by breaking a secondary contact and restraining an arc. Repetitive motions of the DC relay are achieved by using the MOS-FET as a formation element. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、直流リレーの接点の高電圧化、大電流化に関するものである。 The present invention relates to an increase in voltage and current of a contact of a DC relay.

従来の直流リレーにおいては、高電圧，大電流化を図ろうとすると、リレー開極時に発生する接点間のアークを遮断する為に消弧装置を組み込む必要があるため、小型化できず、コストが高くならざるを得なかった。 In conventional DC relays, when trying to increase the voltage and current, it is necessary to incorporate an arc extinguishing device to interrupt the arc between the contacts that occurs when the relay is opened. I had to get higher.

一方、小型、低価格で高電圧，大電流化の要求は根強く、直流回路に主接点及び副接点を直列にし、主接点と並列に転流回路を設け、先に主接点を開極し回路電流を転流回路に転流させ、電流を限流させた後、副接点を開極させることで、アークを抑えて直流回路を開路させる試みは、色々となされてきた。 On the other hand, there is a strong demand for high voltage and large current at a small size and low price. The main contact and sub-contact are connected in series with the DC circuit, a commutation circuit is provided in parallel with the main contact, and the main contact is opened first. Various attempts have been made to open the DC circuit while suppressing the arc by commutating the current to the commutation circuit, limiting the current, and opening the sub-contact.

特に、転流回路にＰＴＣを用いた方式が、小型で簡素な構成例として提案されている。
（特開２０００−６７７１０号公報）In particular, a method using PTC in the commutation circuit has been proposed as a small and simple configuration example.
(JP 2000-67710 A)

しかし、上記ＰＴＣを転流回路に用いた提案においては、ＰＴＣが熱反応素子である為、転流後の限流の応答速度が遅く、この傾向は、定格の大きいＰＴＣを使用するに従って顕著になる。
又、復旧時には、放熱が必要である為、限流時の応答に比べ更に時間がかかり、繰り返し動作に不適当である。However, in the proposal using the PTC in the commutation circuit, since the PTC is a thermal reaction element, the response speed of the current limiting after the commutation is slow, and this tendency becomes conspicuous as the rated PTC is used. Become.
Moreover, since heat dissipation is required at the time of recovery, it takes more time than the response at the time of current limiting, and is not suitable for repeated operation.

本発明は、上記問題を解決するためになされたもので、転流回路の構成素子がＰＴＣの場合と比べ、十分に高速応答な素子に替えることで、繰り返し動作に対応できる直流リレーの実現を目的とする。 The present invention has been made to solve the above-mentioned problem, and it is possible to realize a direct current relay that can cope with repetitive operation by replacing the commutation circuit with a sufficiently fast response element as compared with the case of PTC. Objective.

上記目的を達成するために、本発明における転流回路の構成素子として図１に示すようにＦＥＴを採用することで、ＰＴＣに比べ十分な高速応答を確保すると共に、ＦＥＴのゲート電圧をＣＲによる時定数回路を通して制御することで、ＦＥＴが導通状態（オン）から遮断（オフ）になる際に転流電流を滑らかに限流させ、アークを抑えて直流回路を開路させることを特徴とする。又、前記時定数を変更することにより、任意の限流特性を得る事も可能である。 In order to achieve the above object, by adopting an FET as shown in FIG. 1 as a constituent element of a commutation circuit in the present invention, a sufficiently high-speed response is ensured compared to a PTC, and the gate voltage of the FET is determined by CR. By controlling through the time constant circuit, the commutation current is smoothly limited when the FET is turned off from the conductive state (ON), and the DC circuit is opened while suppressing the arc. It is also possible to obtain an arbitrary current limiting characteristic by changing the time constant.

更に、副接点開極後、すみやかにＦＥＴをオフ状態からオン状態に復帰させる事で、引き続き直流回路を閉路，開路とした際、転流回路に限流動作をさせる事が可能となり、繰り返し動作にも対応させる事ができる。 In addition, by immediately returning the FET from the OFF state to the ON state after opening the sub-contact, it is possible to cause the commutation circuit to perform a current limiting operation when the DC circuit is continuously closed or opened. Can also be supported.

以下、本発明の実施例を説明する。図２は本発明のハイブリッド型直流リレーを示す回路図である。ハイブリッド型直流リレーは、外部から制御される主接点１、前期主接点１と時間的に遅れを持って働く副接点２、転流回路の構成素子としてＭＯＳ−ＦＥＴ３、転流回路に流れる電流を電圧降下として検出する抵抗４、抵抗４の電圧降下と設定電圧５を比較して信号を出力するコンパレータ６、コンパレータの信号を受けてオン状態になり、一定時間後にオフ状態になるサイリスタ７、サイリスタ７がオン状態になった際に、ＦＥＴのゲート電圧を低下させる動作速度の調節に時定数として抵抗８とコンデンサ９で構成される。このとき設定電圧５は、主接点１が開極し、ＭＯＳ−ＦＥＴ３に電流が流れた際、抵抗４に発生する電圧降下より低い電圧とし、主接点１が開極したことを検知できる様にする。 Examples of the present invention will be described below. FIG. 2 is a circuit diagram showing a hybrid type DC relay of the present invention. The hybrid type DC relay has a main contact 1 controlled from the outside, a sub-contact 2 working with a time delay from the previous main contact 1, a MOS-FET 3 as a commutation circuit component, and a current flowing through the commutation circuit. A resistor 4 to detect as a voltage drop, a comparator 6 that outputs a signal by comparing the voltage drop of the resistor 4 with the set voltage 5, a thyristor 7 that turns on after receiving a signal from the comparator, and turns off after a certain time, a thyristor A resistor 8 and a capacitor 9 are used as a time constant for adjusting the operation speed for lowering the gate voltage of the FET when 7 is turned on. At this time, the set voltage 5 is set to a voltage lower than the voltage drop generated in the resistor 4 when the main contact 1 is opened and a current flows through the MOS-FET 3 so that the opening of the main contact 1 can be detected. To do.

ＭＯＳ−ＦＥＴ３は、開路時に転流回路として動作する以外は常にオン状態である。 The MOS-FET 3 is always on except that it operates as a commutation circuit when the circuit is opened.

直流回路の閉路時には、主接点１が閉極後、副接点２を閉極し回路を閉路する。 When the DC circuit is closed, after the main contact 1 is closed, the sub-contact 2 is closed and the circuit is closed.

直流回路の開路時は、主接点１が開極し、ＭＯＳ−ＦＥＴ３が転流路となり、主接点１の開極を転流電流による電圧降下の増加として抵抗４で検知する。抵抗４の電圧降下が設定電圧５より高くなったことをコンパレータ６が検出し、サイリスタ７のゲートへ信号を出力する。サイリスタ７はゲートに信号が与えられた事でオン状態になり、ＭＯＳ−ＦＥＴ３のゲート電圧を低下させ、回路電流を限流させる。このとき抵抗８とコンデンサ９によるＣＲ時定数回路を構成する事で滑らかに回路電流を限流することができ、電流遮断時に発生する動作過電圧を低減又は発生させないことを可能とする。更にサージ吸収ダイオード１０を設けることにより、より効果的に動作過電圧を低減させることもできる。 When the DC circuit is opened, the main contact 1 is opened and the MOS-FET 3 becomes a commutation path, and the opening of the main contact 1 is detected by the resistor 4 as an increase in voltage drop due to the commutation current. The comparator 6 detects that the voltage drop of the resistor 4 has become higher than the set voltage 5 and outputs a signal to the gate of the thyristor 7. The thyristor 7 is turned on when a signal is given to the gate, and the gate voltage of the MOS-FET 3 is lowered to limit the circuit current. At this time, by forming a CR time constant circuit with the resistor 8 and the capacitor 9, the circuit current can be smoothly limited, and the operation overvoltage generated when the current is interrupted can be reduced or not generated. Furthermore, by providing the surge absorbing diode 10, the operating overvoltage can be reduced more effectively.

副接点２の開極は、ＭＯＳ−ＦＥＴ３によって電流が十分絞られた状態で開極するためアーク発生の心配はない。抵抗８，抵抗１１，抵抗１２の抵抗値を選択することで、副接点が開極した後、一定時間後にサイリスタ７がオフ状態に復帰し、ＭＯＳ−ＦＥＴ３がオン状態になる事で繰り返し動作を可能とする。 Since the opening of the sub-contact 2 is performed in a state where the current is sufficiently reduced by the MOS-FET 3, there is no concern about the occurrence of an arc. By selecting the resistance values of the resistors 8, 11, and 12, the thyristor 7 returns to the off state after a certain time after the sub-contact opens, and the MOS-FET 3 is turned on to repeat the operation. Make it possible.

ここで、本回路の効果を図３及び図５に示す実験回路を用いて行った結果について説明する。 Here, results obtained by using the experimental circuit shown in FIGS. 3 and 5 to explain the effect of this circuit will be described.

まず、図３は、主接点１のみを用いたもので、主接点１に接点定格ＤＣ３０Ｖ，２０Ａのリレーを単独で使用し、負荷を通してＤＣ６０Ｖ，５Ａ通電した後、主接点１を開極すると，図４のような波形となり、電流を遮断することができずアークによる続流が発生した。First, FIG. 3 uses only the main contact 1. When a relay having a contact rating of DC 30 V and 20 A is used alone for the main contact 1, and the DC 60 V and 5 A are energized through the load, the main contact 1 is opened. The waveform shown in FIG. 4 was obtained, and the current could not be interrupted, and a follow-up flow due to an arc occurred.

図５に示すように、主接点１と並列にＭＯＳ−ＦＥＴ３に定格２００Ｖ，３０Ａ，オン抵抗３８ｍΩのＭＯＳ−ＦＥＴ３を接続し、主接点１と直列に副接点２を接続した場合は、同様の直流電圧ＤＣ６０Ｖ，５Ａに対して図６のように主接点１の開極により主接点１に流れていた電流が、ＭＯＳ−ＦＥＴ３に転流し、電流が限流され主接点にアークを発生させることなく開極動作している。 As shown in FIG. 5, when the MOS-FET 3 having a rating of 200 V, 30 A and on-resistance of 38 mΩ is connected to the MOS-FET 3 in parallel with the main contact 1, and the sub-contact 2 is connected in series with the main contact 1, the same As shown in FIG. 6, with respect to the DC voltage DC60V, 5A, the current flowing through the main contact 1 due to the opening of the main contact 1 is commutated to the MOS-FET 3, and the current is limited to generate an arc at the main contact. There is no opening operation.

発明の効果The invention's effect

以上のように本考案は、外部から制御される可能な主接点と時間的に遅れを持って働く副接点とＭＯＳ−ＦＥＴとを組み合わせ、アークが発生しない直流リレーを実現することで接点容量を拡大させ、且つ転流回路の構成素子にＭＯＳ−ＦＥＴを用いる事で繰り返し動作に対応できる直流リレーを可能とした。As described above, the present invention combines a possible main contact that is controlled from the outside, a sub-contact that works with a delay in time, and a MOS-FET, thereby realizing a direct current relay that does not generate an arc, thereby increasing the contact capacity. A DC relay that can handle repeated operations is made possible by expanding and using MOS-FETs as components of the commutation circuit.

本発明のハイブリッド型直流リレーの概略を示す説明図Explanatory drawing which shows the outline of the hybrid type DC relay of this invention 本発明のハイブリッド型直流リレーを装備した電気回路図Electrical circuit diagram equipped with the hybrid type DC relay of the present invention 本発明の実施例として示した主接点のみを接続した回路での構成図The block diagram in the circuit which connected only the main contact shown as an Example of this invention 図３の構成図に示す回路構成で行った際の試験結果Test results when the circuit configuration shown in FIG. 3 is used. 本発明の実施例として示した主接点１と並列に転流回路を接続し、主接点１と直列に副接点２を接続した回路での構成図The block diagram in the circuit which connected the commutation circuit in parallel with the main contact 1 shown as the Example of this invention, and connected the subcontact 2 in series with the main contact 1 図５の構成図に示す回路構成で行った際の試験結果Test results for the circuit configuration shown in the configuration diagram of FIG.

符号の説明Explanation of symbols

１主接点
２副接点
３ＭＯＳ−ＦＥＴ
４抵抗
５設定電圧
６コンパレータ
７サイリスタ
８抵抗
９コンデンサ
１０サージ吸収ダイオード
１１抵抗
１２抵抗
１３転流回路1 Main contact 2 Sub contact 3 MOS-FET
4 Resistor 5 Set Voltage 6 Comparator 7 Thyristor 8 Resistor 9 Capacitor 10 Surge Absorption Diode 11 Resistor 12 Resistor 13 Commutation Circuit

Claims

直流回路にそれぞれ直列に接続された主接点及び副接点と、前記主接点と並列接続されたＦＥＴを構成素子とした転流回路とを備え、前記直流回路の閉路時には、転流回路をオンにし、主接点が閉極したのち副接点が閉極し、前記直流回路の開路時には、転流回路はオン状態で副接点より先に主接点を開極し、次に前記転流回路をオフにすることで回路電流を限流したのち、副接点を開極することを特徴とするハイブリッド型直流リレーA main contact and a sub-contact connected in series to the DC circuit, and a commutation circuit comprising FETs connected in parallel with the main contact as constituent elements. When the DC circuit is closed, the commutation circuit is turned on. After the main contact is closed, the sub contact is closed, and when the DC circuit is opened, the commutation circuit is in an ON state, the main contact is opened before the sub contact, and then the commutation circuit is turned off. The hybrid type DC relay is characterized by opening the sub-contact after limiting the circuit current.

転流回路は、主接点の開極を検知し、ＦＥＴを制御することによって回路電流の限流を行い、ＦＥＴがオフした後副接点が開極し、副接点開極後はその後の動作準備として一定時間後、ＦＥＴをオンにすることを特徴とする請求項１記載のハイブリッド型直流リレーThe commutation circuit detects the opening of the main contact and controls the FET to limit the circuit current. After the FET is turned off, the sub-contact opens, and after the sub-contact opens, the subsequent operation is ready. 2. The hybrid DC relay according to claim 1, wherein the FET is turned on after a predetermined time.