JPH0623194Y2 - Current unbalance detection circuit for bridge rectification circuit by parallel connection rectification element - Google Patents
Current unbalance detection circuit for bridge rectification circuit by parallel connection rectification elementInfo
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- JPH0623194Y2 JPH0623194Y2 JP1986133823U JP13382386U JPH0623194Y2 JP H0623194 Y2 JPH0623194 Y2 JP H0623194Y2 JP 1986133823 U JP1986133823 U JP 1986133823U JP 13382386 U JP13382386 U JP 13382386U JP H0623194 Y2 JPH0623194 Y2 JP H0623194Y2
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Description
【考案の詳細な説明】 Ａ．産業上の利用分野 本考案は並列接続整流素子によるブリッジ整流回路の電
流不平衡検出回路に関するものである。Detailed Description of the Invention A. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current imbalance detection circuit for a bridge rectification circuit using parallel connection rectification elements.
Ｂ．考案の概要 本考案は並列接続整流素子によるブリッジ整流回路の電
流不平衡検出回路において、 各相の並列整流素子に夫々流れる電流を検出する電流検
出器と、平均電流を演算する平均電流演算回路と、前記
整流素子の並列素子の並列接続数に等しい数のゲート信
号を出力する分配器と、前記ゲート信号により前記検出
電流を順次通過させるスイッチと、この検出電流と平均
電流演算回路の平均出力電流とを比較する比較器とから
なるものであって、 整流素子並列数が多くなっても比較器の個数を増加させ
ずに済ますことができるものである。B. SUMMARY OF THE INVENTION The present invention relates to a current imbalance detection circuit for a bridge rectification circuit using parallel-connected rectification elements, a current detector that detects the current that flows in each phase parallel rectification element, and an average current calculation circuit that calculates the average current. A divider for outputting a gate signal of a number equal to the number of parallel elements of the rectifying element connected in parallel, a switch for sequentially passing the detected current by the gate signal, and an average output current of the detected current and average current calculation circuit. It is composed of a comparator for comparing and, and even if the number of rectifying elements in parallel increases, the number of comparators need not be increased.
Ｃ．従来の技術 電力変換装置等においては、大電流を得るためにサイリ
スタブリッジ整流回路の各アームに使用されている整流
素子を並列に接続することがある。例えば、並列接続し
た整流素子に均等に電流が流れる場合には、特に不都合
はないが、各整流素子に不均一に流れる場合には整流素
子を破壊させることになるので、不平衡を検出し、不平
衡が過大の場合速やかに対策を取る必要がある。C. 2. Description of the Related Art In power converters and the like, rectifying elements used in each arm of a thyristor bridge rectifier circuit may be connected in parallel to obtain a large current. For example, if current flows evenly through the rectifying elements connected in parallel, there is no particular problem, but if the current flows unevenly through each rectifying element, the rectifying element will be destroyed, so imbalance is detected, If the imbalance is excessive, it is necessary to take immediate measures.
従来、並列接続整流素子の電流不平衡検出回路として
は、第３図及び第４図に示すものが知られている。第３
図，第４図はサイリスタブリッジ整流回路の１つの相を
整流素子３個並列接続して構成した例を示し、第３図に
示す電流不平衡検出回路は並列接続された整流素子５
１，５２，５３、各整流素子の回路に設けられた電流用
変流器５４，５５，５６及び比較器５７，５８，５９か
ら成る。整流素子５１，５２，５３のアノード端側に挿
入した変流器５４，５５は比較器５７に接続してあり、
変流器５５，５６は比較器５８に接続してある。また変
流器５４，５６は比較器５９に接続してある。変流器５
４，５５，５６を流れる電流が不平衡である場合は、比
較器５７，５８，５９から電流不平衡であることを示す
比較電流を出力する。比較器５７，５８，５９から比較
電流が出力する場合は図示しない警報器の警報を鳴動さ
せる。Conventionally, as a current imbalance detection circuit for a parallel-connected rectifying element, those shown in FIGS. 3 and 4 are known. Third
4 and 5 show an example in which one phase of a thyristor bridge rectifier circuit is connected in parallel with three rectifier elements, and the current imbalance detection circuit shown in FIG. 3 has a rectifier element 5 connected in parallel.
1, 52, 53, current transformers 54, 55, 56 and comparators 57, 58, 59 provided in the circuits of the respective rectifying elements. The current transformers 54 and 55 inserted on the anode end side of the rectifying elements 51, 52 and 53 are connected to a comparator 57,
The current transformers 55 and 56 are connected to the comparator 58. The current transformers 54 and 56 are connected to the comparator 59. Current transformer 5
When the currents flowing through 4, 55 and 56 are unbalanced, the comparators 57, 58 and 59 output comparison currents indicating that the currents are unbalanced. When the comparison currents are output from the comparators 57, 58, 59, an alarm of an alarm device (not shown) is sounded.
また、第４図に示す電流不平衡検出回路は、上記検出回
路の他に平均電流演算回路６０を含めたものである。こ
の平均電流演算回路６０は抵抗６１，６２，６３，６４
及び演算増幅器６５から成る。変流器５４は、平均電流
演算増幅器６０を経て比較器５７に接続してあると共に
直接比較器５７に接続してある。変流器５５は、平均電
流演算回路６０を経て比較器５８に接続してあると共に
直接、比較器５８に接続してある。また、変流器５６
は、平均電流演算回路６０を経て比較器５９に接続して
あると共に直接、比較器５９に接続してある。これ故
に、本検出回路では、平均電流演算回路６０の出力と電
流用変流器５４，５５，５６を流れる電流の差を比較器
５７，５８，５９で比較する。比較器５７，５８，５９
から比較電流が出力する場合には、図示しない警報器の
警報を鳴動させる。The current imbalance detection circuit shown in FIG. 4 includes an average current calculation circuit 60 in addition to the above detection circuit. The average current calculation circuit 60 includes resistors 61, 62, 63, 64.
And an operational amplifier 65. The current transformer 54 is connected to the comparator 57 via the average current operational amplifier 60 and directly connected to the comparator 57. The current transformer 55 is connected to the comparator 58 via the average current calculation circuit 60 and directly connected to the comparator 58. In addition, the current transformer 56
Is connected to the comparator 59 via the average current calculation circuit 60 and is also directly connected to the comparator 59. Therefore, in this detection circuit, the difference between the output of the average current calculation circuit 60 and the current flowing through the current transformers 54, 55, 56 is compared by the comparators 57, 58, 59. Comparators 57, 58, 59
When the comparison current is output from, an alarm of an alarm device (not shown) is sounded.
Ｄ．考案が解決しようとする問題点 しかし、かかる電流不平衡検出回路は、１相について変
流器５４，５５，変流器５５，５６及び変流器５４，５
６を平均電流に演算回路６０を経てまたは直接、比較器
５７、比較器５８及び比較器５９に接続するものである
から、比較器の台数は１相について整流素子の並列接続
数だけ必要となる。それ故に、３相のブリッジ整流回路
においては、その３倍必要となる。そしてこれらの電流
不平衡検出回路では、比較器の台数を減らすことができ
ないという問題がある。D. However, in the current imbalance detection circuit, the current transformers 54 and 55, the current transformers 55 and 56, and the current transformers 54 and 5 for one phase.
Since 6 is connected to the comparator 57, the comparator 58, and the comparator 59 via the arithmetic circuit 60 or directly to the average current, the number of comparators is equal to the number of rectifying elements connected in parallel for one phase. . Therefore, in a three-phase bridge rectifier circuit, three times that is required. These current imbalance detection circuits have a problem that the number of comparators cannot be reduced.
本考案の目的は、比較器の台数を少なくする此種の整流
回路の電流不平衡検出回路を提供することにある。An object of the present invention is to provide a current imbalance detecting circuit for a rectifier circuit of this type that reduces the number of comparators.
Ｅ．問題点を解決するための手段 上記問題点を解決するための手段として本考案は、各相
の整流素子を並列接続してなる整流器と、前記整流素子
に供給する電流を検出する電流検出器と、前記電流検出
器で検出した検出電流を平均電流に演算する平均電流演
算回路と、前記整流素子の並列接続数に等しい数のゲー
ト信号を出力するパルス分配器と、前記ゲート信号によ
り前記検出電流を通過させるスイッチと、前記検出電流
と前記平均電流演算回路の平均出力電流とを比較する比
較器とからなることを特徴とする。E. Means for Solving the Problems As a means for solving the above problems, the present invention provides a rectifier in which rectifying elements of each phase are connected in parallel, and a current detector for detecting a current supplied to the rectifying element. An average current calculation circuit that calculates a detection current detected by the current detector as an average current, a pulse distributor that outputs a number of gate signals equal to the number of parallel connections of the rectifying elements, and the detection current by the gate signal. And a comparator for comparing the detected current with the average output current of the average current calculation circuit.
Ｆ．作用 本電流不平衡検出回路は、比較器の入力側に整流器の整
流素子並列数に相当する数のスイッチを設け、そのスイ
ッチを順番に開閉し、前記整流素子並列数が多くなって
も比較器の個数を増加しなくて済ませることができる。F. Function The current imbalance detection circuit is provided with the number of switches corresponding to the number of parallel rectifier elements of the rectifier on the input side of the comparator, and the switches are opened and closed in order to increase the number of parallel rectifier elements. It is not necessary to increase the number of.
Ｇ．実施例 次に、本考案の一実施例を添附図面に基づいて詳細に説
明する。G. Embodiment Next, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.
第１図は本考案電流不平衡検出回路の一実施例を示す回
路図で、交流入力のａ相，ｂ相，ｃ相の各相を、３個の
サイリスタを並列接続して３相ブリッジ整流回路を構成
した場合の例である。FIG. 1 is a circuit diagram showing an embodiment of the current imbalance detection circuit of the present invention, in which three phases of AC input a-phase, b-phase, and c-phase are connected in parallel and three-phase bridge rectification is performed. It is an example of a case where a circuit is configured.
この図において、符号１はブリッジ整流回路で、ブリッ
ジ整流回路１は３相の各相ａ，ｂ，ｃの整流部２，３，
４を３相ブリッジに接続したもので、交流電流を直流電
流に交換する。ａ相の整流部２はサイリスタ２ａ，２
ｂ，２ｃを並列接続し、また前記サイリスタ２ａ，２
ｂ，２ｃと直列にサイリスタ２ｄ，２ｅ，２ｆを接続し
て構成されている。また、ｂ相，ｃ相の整流部３，４に
ついては整流部２と同様なので、詳細な説明を省略す
る。交流入力のａ相は整流部２と接続してあり、交流入
力のｂ相は整流部３と接続してある。また交流入力のｃ
相には整流部４が接続してある。以上整流部２，３，４
で３相ブリッジ回路が構成される。サイリスタ２ａのア
ノード側に挿入されているのは、変流器（以下「ＣＴ」
と省略する。）５で、サイリスタ２ｂのアノード側に挿
入されているのはＣＴ６であり、サイリスタ２ｃのアノ
ード側に挿入されているのはＣＴ７である。ＣＴ５とタ
ーミナル８を介して接続してあるのは、抵抗１１及びス
イッチ１２である。ＣＴ６とターミナル９を介して接続
してあるのは、抵抗１３及びスイッチ１４である。また
ＣＴ７とターミナル１０を介して接続してあるのは、抵
抗１５とスイッチ１６である。前記抵抗１３に接続して
あるのは、演算増幅器１７で、この演算増幅器１７の入
力側と出力側の間に接続されているのが、抵抗１８で
あ。平均電流演算回路１９は抵抗１１，１３，１５，１
８及び演算増幅器１７から成る回路で、ａ相の整流部２
の各並列素子２ａ，２ｂ，２ｃに流れる電流の平均電流
を演算し、入力抵抗である抵抗１１，１３，１５を同一
抵抗値のものでそろえた場合、演算増幅器１７のゲイン
は１／３になる。一方、パルス発振器２０は一定周期の
パルス信号をパルス分配器に送出し、整流素子並列数だ
けパルスを分配する。パルス分配器２１の端子ｄは、前
記スイッチ１２に接続してあり、パルス分配器２１の端
子ｅは前記スイッチ１４に接続してあり、またパルス分
配器２１の端子ｆは前記スイッチ１６に接続してある。
スイッチ１２に接続してあるのは抵抗２２であり、スイ
ッチ１４に接続してあるのが抵抗２３である。またスイ
ッチ１６には抵抗２４が接続してある。ゲートパルス１
０１，１０２，１０３は、スイッチ１２，１４，１６を
順次閉じるためのパルス信号で、第２図に示すものであ
る。また演算増幅回路１７は抵抗２５、抵抗２６を介し
てバイアス設定器２７に接続されている。In the figure, reference numeral 1 is a bridge rectifier circuit, and the bridge rectifier circuit 1 is a rectifier unit 2, 3, for each of the three phases a, b, c.
4 is connected to a three-phase bridge to exchange AC current with DC current. The a-phase rectifier 2 is composed of thyristors 2a and 2a.
b and 2c are connected in parallel, and the thyristors 2a and 2c
It is configured by connecting thyristors 2d, 2e and 2f in series with b and 2c. Further, the b-phase and c-phase rectifiers 3 and 4 are the same as the rectifier 2, so detailed description thereof will be omitted. The AC input a-phase is connected to the rectifying unit 2, and the AC input b-phase is connected to the rectifying unit 3. AC input c
The rectification part 4 is connected to the phase. The rectifying section 2, 3, 4
A three-phase bridge circuit is configured with. Inserted on the anode side of the thyristor 2a is a current transformer (hereinafter "CT").
Is omitted. 5), CT6 is inserted on the anode side of the thyristor 2b, and CT7 is inserted on the anode side of the thyristor 2c. The resistor 11 and the switch 12 are connected to the CT 5 via the terminal 8. The resistor 13 and the switch 14 are connected to the CT 6 via the terminal 9. Also, a resistor 15 and a switch 16 are connected to the CT 7 via the terminal 10. The operational amplifier 17 is connected to the resistor 13, and the resistor 18 is connected between the input side and the output side of the operational amplifier 17. The average current calculation circuit 19 includes resistors 11, 13, 15, 1
8 and an operational amplifier 17, a phase rectifier 2 of a phase
When the average currents of the currents flowing in the respective parallel elements 2a, 2b, 2c are calculated and the resistors 11, 13, 15 which are the input resistances have the same resistance value, the gain of the operational amplifier 17 becomes 1/3. Become. On the other hand, the pulse oscillator 20 sends out a pulse signal of a constant cycle to the pulse distributor, and distributes the pulse by the number of parallel rectifying elements. The terminal d of the pulse distributor 21 is connected to the switch 12, the terminal e of the pulse distributor 21 is connected to the switch 14, and the terminal f of the pulse distributor 21 is connected to the switch 16. There is.
A resistor 22 is connected to the switch 12, and a resistor 23 is connected to the switch 14. A resistor 24 is connected to the switch 16. Gate pulse 1
Reference numerals 01, 102 and 103 are pulse signals for sequentially closing the switches 12, 14 and 16 and are shown in FIG. The operational amplifier circuit 17 is also connected to the bias setter 27 via the resistors 25 and 26.
次に、本実施例の作用について説明する。Next, the operation of this embodiment will be described.
先ず、交流入力のａ，ｂ，ｃの各相から交流電流を整流
部２，３，４に供給する。すると、整流部２について説
明すると、平均電流演算回路１９には、整流部２の各並
列整流素子に流れる電流に比例した電流が入力され、そ
の平均値が演算される。一方、点Ａで分岐した検出電流
１００はスイッチ１２に流れる。このとき、パルス分配
器２１で一定周期のパルスに分配されたゲートパルス１
０１がスイッチ１２に印加し、スイッチ１２を閉じる。
このとき、比較器２８には、前記平均電流演算回路１９
の出力電流１０６と前記検出電流１００が入力される。
この比較器２８では、前記出力電流１０６と検出電流１
００とを比較し、両電流間に差が生じ、その差が所定値
を超えた場合に比較電流１０７を図示しない警報器に入
力し、警報器の警報を鳴動させる。ＣＴ６の検出電流１
０４及びＣＴ７の検出電流１０５についても上記と同様
にして、比較器２８で比較し、検出電流と平均電流との
間に差が生じた場合に比較電流１０７を図示しない警報
器に入力し、警報器の警報を鳴動させる。First, an alternating current is supplied to the rectifying units 2, 3, and 4 from each phase of a, b, and c of the alternating current input. Then, the rectification unit 2 will be described. A current proportional to the current flowing through each parallel rectification element of the rectification unit 2 is input to the average current calculation circuit 19, and the average value thereof is calculated. On the other hand, the detection current 100 branched at the point A flows to the switch 12. At this time, the gate pulse 1 distributed by the pulse distributor 21 into pulses of a constant cycle
01 applies to the switch 12, and the switch 12 is closed.
At this time, the average current calculation circuit 19 is included in the comparator 28.
Output current 106 and the detection current 100 are input.
In the comparator 28, the output current 106 and the detected current 1
00, a difference is generated between both currents, and when the difference exceeds a predetermined value, the comparison current 107 is input to an alarm device (not shown) and the alarm of the alarm device is sounded. CT6 detection current 1
In the same manner as above, the comparators 28 and 04 also detect the detected current 105, and when a difference occurs between the detected current and the average current, the comparative current 107 is input to an alarm device (not shown) to generate an alarm. Sound the alarm of the vessel.
本実施例の電流不平衡検出回路によれば、比較器の入力
側に整流器の整流素子並列数に相当する数のスイッチを
設け、そのスイッチを順番に、開閉させることができる
ので、整流素子並列数が多くなっても比較器の個数を増
加する必要がない。According to the current imbalance detection circuit of the present embodiment, the number of switches corresponding to the number of parallel rectifier elements of the rectifier is provided on the input side of the comparator, and the switches can be opened and closed in order. Even if the number increases, it is not necessary to increase the number of comparators.
また本実施例の電流不平衡検出回路を用いることによ
り、整流素子電流平均値と各整流素子電流の差を２段階
に分けて軽故障扱い（運転継続）と重故障扱い（運転停
止）にする場合には、比較器を１台増加するだけで簡単
にできる。Further, by using the current imbalance detection circuit of the present embodiment, the difference between the average value of the rectifying element current and each rectifying element current is divided into two stages, which are treated as a light failure (continuous operation) and a heavy failure (stop operation). In that case, this can be easily done by increasing the number of comparators by one.
Ｈ．考案の効果 上記のように本考案によれば、比較器の入力側に整流器
の整流素子並列数に相当する数のスイッチを設け、その
スイッチを順番に開閉させることができるので、整流素
子並列数が多くなっても比較器の個数を増加させずに済
ますことができ、大電流容量のブリッジ整流回路を安価
に構成することができる。H. As described above, according to the present invention, the number of switches corresponding to the number of parallel rectifier elements of the rectifier can be provided on the input side of the comparator, and the switches can be opened and closed in order. It is possible to increase the number of comparators without increasing the number, and a bridge rectifier circuit with a large current capacity can be constructed at low cost.
第１図は本考案電流不平衡検出回路の一実施例を示す回
路図、第２図は各スイッチを閉じる各ゲートパルスのタ
イミングチャートを示すもので、第３図及び第４図は従
来の電流不平衡検出回路の一例を示す回路図である。 １……整流回路、２……整流部、３……整流部、４……
整流部、５……ＣＴ、６……ＣＴ、７……ＣＴ、８……
ターミナル、９……ターミナル、１０……ターミナル、
１１……抵抗、１２……スイッチ、１３……抵抗、１４
……スイッチ、１５……抵抗、１６……スイッチ、１７
……演算増幅器、１８……抵抗、１９……平均電流演算
回路、２０……パルス発振器、２１……パルス分配器、
２２〜２６……抵抗、２７……バイアス設定器、２８…
…比較器FIG. 1 is a circuit diagram showing an embodiment of the current imbalance detection circuit of the present invention, FIG. 2 is a timing chart of each gate pulse for closing each switch, and FIGS. 3 and 4 are conventional currents. It is a circuit diagram which shows an example of an imbalance detection circuit. 1 ... Rectifier circuit, 2 ... Rectifier section, 3 ... Rectifier section, 4 ...
Rectifier 5 ... CT, 6 ... CT, 7 ... CT, 8 ...
Terminal, 9 ... Terminal, 10 ... Terminal,
11 ... Resistance, 12 ... Switch, 13 ... Resistance, 14
...... Switch, 15 ...... Resistance, 16 ...... Switch, 17
...... Operational amplifier, 18 ...... Resistance, 19 ...... Average current calculation circuit, 20 ...... Pulse oscillator, 21 ...... Pulse distributor,
22-26 ... Resistance, 27 ... Bias setter, 28 ...
... comparator
Claims (1)
リッジ整流回路であって、前記各相の整流素子を複数個
並列接続してなる整流部と、前記各相の並列整流素子に
夫々流れる電流を検出する電流検出器と、前記各電流検
出器で検出した検出電流を平均電流に演算する平均電流
演算回路と、前記整流素子の並列接続数に等しい数のゲ
ート信号を出力するパルス分配器と、前記ゲート信号に
より前記検出電流を順次通過させるスイッチと、前記各
検出電流と前記平均電流演算回路の平均出力電流とを比
較する比較器とからなることを特徴とする並列接続整流
子素子によるブリッジ整流回路の電流不平衡検出回路。1. A bridge rectifier circuit configured by connecting rectifying elements of each phase in parallel, wherein a rectifying unit formed by connecting a plurality of rectifying elements of each phase in parallel and a parallel rectifying element of each phase. A current detector for detecting each flowing current, an average current calculation circuit for calculating the detection current detected by each current detector as an average current, and a pulse for outputting a number of gate signals equal to the number of parallel connections of the rectifying elements A parallel connection rectifier comprising: a distributor, a switch for sequentially passing the detected current by the gate signal, and a comparator for comparing each detected current with an average output current of the average current calculation circuit. Current imbalance detection circuit for bridge rectification circuit using elements.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1986133823U JPH0623194Y2 (en) | 1986-09-01 | 1986-09-01 | Current unbalance detection circuit for bridge rectification circuit by parallel connection rectification element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1986133823U JPH0623194Y2 (en) | 1986-09-01 | 1986-09-01 | Current unbalance detection circuit for bridge rectification circuit by parallel connection rectification element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6340190U JPS6340190U (en) | 1988-03-15 |
| JPH0623194Y2 true JPH0623194Y2 (en) | 1994-06-15 |
Family
ID=31034487
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1986133823U Expired - Lifetime JPH0623194Y2 (en) | 1986-09-01 | 1986-09-01 | Current unbalance detection circuit for bridge rectification circuit by parallel connection rectification element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0623194Y2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101689501B1 (en) * | 2016-03-03 | 2016-12-23 | 두산중공업 주식회사 | Multiple phase controlled rectifiers with fault detecting apparatus for thryster switch and fault detection method thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54166529U (en) * | 1978-05-15 | 1979-11-22 | ||
| JPS55154480U (en) * | 1979-04-24 | 1980-11-07 | ||
| JPS59161076U (en) * | 1983-04-12 | 1984-10-29 | 三菱電機株式会社 | power supply monitor circuit |
-
1986
- 1986-09-01 JP JP1986133823U patent/JPH0623194Y2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101689501B1 (en) * | 2016-03-03 | 2016-12-23 | 두산중공업 주식회사 | Multiple phase controlled rectifiers with fault detecting apparatus for thryster switch and fault detection method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6340190U (en) | 1988-03-15 |
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