JPH04217816A - Monitor - Google Patents
MonitorInfo
- Publication number
- JPH04217816A JPH04217816A JP2241205A JP24120590A JPH04217816A JP H04217816 A JPH04217816 A JP H04217816A JP 2241205 A JP2241205 A JP 2241205A JP 24120590 A JP24120590 A JP 24120590A JP H04217816 A JPH04217816 A JP H04217816A
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- value
- vdc
- converter
- current
- 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.)
- Granted
Links
- 230000005856 abnormality Effects 0.000 claims abstract description 16
- 238000012806 monitoring device Methods 0.000 claims description 8
- 238000001514 detection method Methods 0.000 abstract description 14
- 230000002411 adverse Effects 0.000 abstract description 8
- 230000002159 abnormal effect Effects 0.000 abstract description 5
- 230000000694 effects Effects 0.000 abstract description 5
- 238000000034 method Methods 0.000 abstract description 2
- 230000005540 biological transmission Effects 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 4
- 230000003321 amplification Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Landscapes
- Power Conversion In General (AREA)
- Inverter Devices (AREA)
- Supply And Distribution Of Alternating Current (AREA)
- Emergency Protection Circuit Devices (AREA)
- Direct Current Feeding And Distribution (AREA)
Abstract
Description
【発明の詳細な説明】
［発明の目的］
（産業上の利用分野）
本発明は直流送電系統、あるいは周波数変換装置等の直
流連系設備の直流電圧検出器の信号が正常であるか否か
を監視する監視装置に関するものである。[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is directed to determining whether the signal of a DC voltage detector of a DC power transmission system or DC interconnection equipment such as a frequency converter is normal. The present invention relates to a monitoring device for monitoring.
（従来の技術）
第２図に、従来の直流送電系統の変換器の制御方式の概
略ブロック図を示す。(Prior Art) FIG. 2 shows a schematic block diagram of a conventional control system for a converter in a DC power transmission system.
変換器１Ａ、１Ｂの直流送電線路３によって接続され、
各変換器１Ａ、１Ｂの直流側はそれぞれ直流リアクトル
２Ａ、２Ｂを介して交流側は変換器用変圧機４Ａ、４Ｂ
、しゃ断器５Ａ、５Ｂを介してそれぞれの交流系統６Ａ
、６Ｂに接続されている。Connected by DC transmission line 3 of converters 1A and 1B,
The DC side of each converter 1A, 1B is connected to a DC reactor 2A, 2B, and the AC side is connected to a converter transformer 4A, 4B.
, each AC system 6A via circuit breakers 5A and 5B.
, 6B.
従来変換器１Ａ、１Ｂには定余裕角制御回路１２Ａ、１
２Ｂ、定電圧制御回路１１Ａ、１１Ｂ、定電流制御回路
１３Ａ、１３Ｂが具備されており、定余裕角制御回路１
２Ａ、１２Ｂはその余裕角設定器１８Ａ、１８Ｂの出力
である余裕角基準値に変換器１Ａ、１Ｂの余裕角が追従
するように動作する。Conventional converters 1A and 1B have constant margin angle control circuits 12A and 1.
2B, constant voltage control circuits 11A, 11B, constant current control circuits 13A, 13B, and constant margin angle control circuit 1.
2A and 12B operate so that the margin angles of the converters 1A and 1B follow the margin angle reference value that is the output of the margin angle setters 18A and 18B.
直流電圧設定器１４Ａ、１４Ｂの出力である電圧基準値
と、直流電圧を直流電圧検出器１５Ａ、１５Ｂで検出し
制御回路にて取り扱い易い値に変換するための電圧／電
圧変換回路１６Ａ、１６Ｂを介してサミング回路１７Ａ
、１７Ｂに入力される直流電圧検出値との差がサミング
回路１７Ａ、１７Ｂで求められ、その差の値が定電圧制
御回路１１Ａ、１１Ｂに入力されることで、直流送電線
路３の直流電圧が前記電圧基準値に追従するように制御
されることになる。The voltage reference value which is the output of the DC voltage setter 14A, 14B, and the voltage/voltage conversion circuit 16A, 16B for detecting the DC voltage with the DC voltage detector 15A, 15B and converting it into a value that can be easily handled by the control circuit. through the summing circuit 17A
, 17B is calculated by the summing circuits 17A, 17B, and the value of the difference is input to the constant voltage control circuits 11A, 11B, so that the DC voltage of the DC power transmission line 3 is adjusted. It will be controlled to follow the voltage reference value.
又、伝送制御回路２６Ａ、２６Ｂの出力である電流基準
値と、直流電流を直流電流検出器２１Ａ、２１Ｂで検出
し電流／電圧変換回路２２Ａ、２２Ｂで制御回路として
取り扱い易い値に変換された直流電流検出値とが、サミ
ング回路２３Ａ、２３Ｂに入力される。In addition, the current reference value that is the output of the transmission control circuits 26A, 26B and the DC current detected by the DC current detectors 21A, 21B and converted to a value that is easy to handle as a control circuit by the current/voltage conversion circuits 22A, 22B are also used. The detected current value is input to summing circuits 23A and 23B.
その差の値が定電流制御回路１３Ａ、１３Ｂに入力され
ることで、直流送電線路３に流れる直流電流が前記電流
基準値に追従するように制御されることになる。By inputting the value of the difference to the constant current control circuits 13A and 13B, the DC current flowing through the DC power transmission line 3 is controlled to follow the current reference value.
スイッチ２４Ａ、２４Ｂは変換器を逆変換器運転する変
換器の方のみが閉となり、電流マージン設定器２５Ａ、
２５Ｂの出力である電流マージンが前記サミング回路２
３Ａ、２３Ｂに入力される。この電流マージンの機能と
、前記定余裕角制御回路１２Ａ、１２Ｂ、前記定電圧制
御回路１１Ａ、１１Ｂ、前記定電流制御回路１３Ａ、１
３Ｂの出力のうちその出力として最も変換器の制御角の
進んでいる出力のみをその出力とする制御進み角優先回
路２８Ａ、２８Ｂの機能とにより、今仮りにスイッチ２
４Ｂが閉で、スイッチ２４Ａが開になっているとすると
、前記制御進み角優先回路２８Ａには、前記定電流制御
回路１３Ａの出力が出力され、前記制御進み角優先回路
２８Ｂには前記低余裕角制御回路１２Ｂ、前記定電圧制
御回路１１Ｂの出力のうち、制御角として進んでいる方
の出力、一般には前記定電圧制御回路１１Ｂの出力が出
力される。それぞれの前記制御進み角優先回路２８Ａ、
２８Ｂの出力は、位相制御回路２９Ａ、２９Ｂに入力さ
れ、ここで変換器の点弧タイミングを決めるパルス信号
に変換され、パルス増幅回路３０Ａ、３０Ｂを介して各
変換器にゲートパルス信号として与えられるように構成
されている。The switches 24A and 24B are closed only for the converter that operates the converter in reverse, and the current margin setter 25A,
The current margin which is the output of 25B is the summing circuit 2.
It is input to 3A and 23B. This current margin function, the constant margin angle control circuits 12A, 12B, the constant voltage control circuits 11A, 11B, the constant current control circuits 13A, 1
With the function of the control advance angle priority circuits 28A and 28B which output only the output of the converter whose control angle is most advanced among the outputs of the switch 3B, the switch 2
4B is closed and the switch 24A is open, the output of the constant current control circuit 13A is output to the control advance angle priority circuit 28A, and the low margin is output to the control advance angle priority circuit 28B. Among the outputs of the angle control circuit 12B and the constant voltage control circuit 11B, the output that is leading as a control angle, generally the output of the constant voltage control circuit 11B, is output. Each of the control advance angle priority circuits 28A,
The output of 28B is input to phase control circuits 29A and 29B, where it is converted into a pulse signal that determines the firing timing of the converter, and is given as a gate pulse signal to each converter via pulse amplification circuits 30A and 30B. It is configured as follows.
以上説明したように制御回路を構成することは公知の技
術である。Configuring the control circuit as described above is a known technique.
（発明が解決しようとする課題）
第２図の従来例では、直流電圧検出に異常が生じた場合
に、次の如き不具合がある。(Problems to be Solved by the Invention) The conventional example shown in FIG. 2 has the following problems when an abnormality occurs in DC voltage detection.
直流電圧検出量が減少方向の異常となった場合、定電圧
制御回路により直流電圧が増大しシステムダウンに至る
恐れが有る。また、変換器に損傷を与えたり、系統に悪
影響を及ぼす。If the detected amount of DC voltage becomes abnormal in a decreasing direction, there is a possibility that the DC voltage will increase due to the constant voltage control circuit, leading to system down. It may also damage the converter and adversely affect the grid.
本発明の目的は前記従来例のもつ不具合を解決するもの
で、直流電圧の検出に異常が生じた場合に、その異常を
検出し、システムに悪影響を与えたり、変換器に損傷を
与えたり、系統へ悪影響を与えたりすることを防ぐため
の監視装置を提供す較する電圧比較手段を具備し、前記
電圧比較手段が不一致検出し、且つ前記直流電圧比較手
段が不一致検出し、且つ前記直流電圧算出値比較手段が
一致検出した場合、直流電圧検出器の異常を判断する。An object of the present invention is to solve the problems of the conventional example, and to detect the abnormality when an abnormality occurs in the detection of DC voltage, and to prevent the abnormality from adversely affecting the system or damaging the converter. Provided is a monitoring device for preventing adverse effects on the grid, and is provided with a voltage comparing means for comparing, the voltage comparing means detecting a mismatch, the DC voltage comparing means detecting a mismatch, and the DC voltage If the calculated value comparison means detects a match, it is determined that there is an abnormality in the DC voltage detector.
（作用）
上記問題を解決するための手段が、どの様に作用するか
説明する。交流電圧の検出値と直流電流の検出値をある
一定周期毎に読み込み、その値から直流電圧値を算出し
、その値と直流電圧の検出値とを比較し、値が等しくな
い場合には直流電圧の一回前の読み込み値と、現在の読
み込み値を比較し値が等しくなく、且つ算出した直流電
圧値の一回前の値と現在の値が一致した場合に直流電圧
検出器の異常と判断する。(Operation) How the means for solving the above problem functions will be explained. Read the detected AC voltage value and the detected DC current value at certain regular intervals, calculate the DC voltage value from those values, compare that value with the detected DC voltage value, and if the values are not equal, Compare the previous voltage read value and the current read value, and if the values are not equal, and the calculated DC voltage value matches the current value, it is determined that the DC voltage detector is abnormal. to decide.
（実施例）
第１図は本発明による実施例の構成を説明する図である
。第１図では、第２図と同じ機能を遂行する装置には同
じ符号を符してある。直流連系設備の監視装置１００Ａ
、１００Ｂは、直流電圧算出器８１Ａ、８１Ｂと、検出
異常判定器８０Ａ、８０Ｂとから構成している。(Embodiment) FIG. 1 is a diagram illustrating the configuration of an embodiment according to the present invention. In FIG. 1, devices that perform the same functions as in FIG. 2 are given the same reference numerals. DC interconnection equipment monitoring device 100A
, 100B are composed of DC voltage calculators 81A, 81B and detection abnormality determiners 80A, 80B.
制御回路中における監視装置の作用については両変換器
について同じものなので、ここでは変換器１Ａについて
の監視装置の作用についてのみのべる。Since the operation of the monitoring device in the control circuit is the same for both converters, only the operation of the monitoring device for converter 1A will be described here.
直流電圧算出器８１Ａは、直流電流検出器２１Ａで検出
され、電流／電圧変換回路２２Ａで制御回路として取り
扱い易い値に変換された直流電流値Ｉｄと交流電圧Ｖａ
ｃをある一定周期で読み込み＊α；制御遅れ角
Ｘｃ；一相分の転流リアクタンス
の式に基づき直流電圧算出値Ｖｄｃ′を求める。The DC voltage calculator 81A calculates the DC current value Id and the AC voltage Va detected by the DC current detector 21A and converted by the current/voltage conversion circuit 22A into values that are easy to handle as a control circuit.
c is read at a certain period *α; control delay angle Xc; DC voltage calculation value Vdc' is determined based on the equation of commutation reactance for one phase.
検出異常判定器８０Ａでは、直流電圧検出器１５Ａで検
出され、制御回路にて取り扱い易い値に変換するための
電圧／電圧変換回路１６Ａを介した値の直流電圧をある
一定周期で読み込み読み込んだＶｄｃの値と直流電圧算
出器の出力である直流電圧算出値Ｖｄｃ′の値を比較し
、等しくない場合には直流電圧算出値Ｖｄｃ′と一回前
の直流電圧算出値Ｖｄｃ−１′の比較と、直流電圧検出
値Ｖｄｃと一回前の直流電圧検出値Ｖｄｃ−１の比較を
行いＶｄｃ′＝Ｖｄｃ−１′であり且つ
Ｖｄｃ＝Ｖｄｃ−１の場合に
直流電圧検出異常と判断し、直流電圧検出異常信号を定
電圧制御回路１１Ａへ出力する。The detection abnormality determiner 80A reads the DC voltage detected by the DC voltage detector 15A and passed through the voltage/voltage conversion circuit 16A to convert it into a value that can be easily handled by the control circuit at a certain period. The value of is compared with the value of the DC voltage calculation value Vdc' which is the output of the DC voltage calculator, and if they are not equal, the DC voltage calculation value Vdc' and the previous DC voltage calculation value Vdc-1' are compared. , the DC voltage detection value Vdc is compared with the previous DC voltage detection value Vdc-1, and if Vdc' = Vdc-1' and Vdc = Vdc-1, it is determined that the DC voltage detection is abnormal, and the DC voltage is A detected abnormality signal is output to the constant voltage control circuit 11A.
直流電圧の検出に異常が発生した場合には、検出異常を
判断し、定電圧制御回路１１へ出力することにより、制
御系が多重の場合には定電圧制御回路で前置保持等の処
理を行い、故障系列を解列して健全系列で制御を行うこ
とにより、システムに悪影響を与えない。If an abnormality occurs in the detection of DC voltage, the detection abnormality is determined and outputted to the constant voltage control circuit 11. If the control system is multiplexed, the constant voltage control circuit can perform processing such as pre-holding. By decoupling the faulty series and performing control using the healthy series, the system is not adversely affected.
また、制御系が一重の場合には、定電圧制御回路で前置
保持等の処理を行いソフト停止するので、変換器に損傷
を与えたり交流系統に悪影響を与えたりすることを防ぐ
ことができる。In addition, when the control system is single, the constant voltage control circuit performs processing such as pre-holding and performs a soft stop, which prevents damage to the converter and adverse effects on the AC system. .
［発明の効果］
以上説明したように、本発明によれば、直流連系設備で
、直流電流の検出及び直流電圧の検出に以上が生じた場
合にその検出異常を判別できるのでシステムに悪影響を
与えたり、変換器に損傷を与えたり、系統へ悪影響を与
えたりすることを防ぐことが出来る。[Effects of the Invention] As explained above, according to the present invention, when an abnormality occurs in the detection of DC current or DC voltage in DC interconnection equipment, the detection abnormality can be determined, so that the system is not adversely affected. This can prevent damage to the converter, damage to the converter, and adverse effects on the system.
第１図は本発明を直流連系設備に適用した場合の一実施
例を示すブロック図、第２図は従来装置のブロック図で
ある。
１Ａ、１Ｂ…変換器、
２Ａ、２Ｂ…直流リアクトル、
３…直流送電線路、
４Ａ、４Ｂ…変換器用変圧器、
５Ａ、５Ｂ…しゃ断器、
６Ａ、６Ｂ…交流系統、
９Ａ、９Ｂ…電圧検出用変圧器、
１１Ａ、１１Ｂ…定電圧制御回路、
１２Ａ、１２Ｂ…定余裕角制御回路、
１３Ａ、１３Ｂ…定電流制御回路、
１４Ａ、１４Ｂ…直流電圧設定器、
１５Ａ、１５Ｂ…直流電圧検出器、
１６Ａ、１６Ｂ…電圧／電圧変換回路、１７Ａ、１７Ｂ
、２３Ａ、２３Ｂ…サミング回路、１８Ａ、１８Ｂ…余
裕角設定器、
１９…伝送回路、
２１Ａ、２１Ｂ…直流電流検出器、
２２Ａ、２２Ｂ…電流／電圧変換回路、２４Ａ、２４Ｂ
…スイッチ、
２５Ａ、２５Ｂ…電流マージン設定器、２６Ａ、２６Ｂ
…伝送制御回路、
２７…電流基準値出力、
２８Ａ、２８Ｂ…制御進み角優先回路、２９Ａ、２９Ｂ
…位相制御回路、
３０Ａ、３０Ｂ…パルス増幅回路、
８０Ａ、８０Ｂ…検出異常判定器、
８１Ａ、８１Ｂ…直流電圧算出器、
１００Ａ、１００Ｂ…監視装置。
代理人 弁理士 則近憲佑FIG. 1 is a block diagram showing an embodiment of the present invention applied to DC interconnection equipment, and FIG. 2 is a block diagram of a conventional device. 1A, 1B...Converter, 2A, 2B...DC reactor, 3...DC transmission line, 4A, 4B...Converter transformer, 5A, 5B...breaker, 6A, 6B...AC system, 9A, 9B...for voltage detection Transformer, 11A, 11B...constant voltage control circuit, 12A, 12B...constant margin angle control circuit, 13A, 13B...constant current control circuit, 14A, 14B...DC voltage setter, 15A, 15B...DC voltage detector, 16A , 16B...Voltage/voltage conversion circuit, 17A, 17B
, 23A, 23B...Summing circuit, 18A, 18B...Margin angle setter, 19...Transmission circuit, 21A, 21B...DC current detector, 22A, 22B...Current/voltage conversion circuit, 24A, 24B
...Switch, 25A, 25B...Current margin setter, 26A, 26B
...Transmission control circuit, 27...Current reference value output, 28A, 28B...Control advance angle priority circuit, 29A, 29B
...Phase control circuit, 30A, 30B...Pulse amplifier circuit, 80A, 80B...Detection abnormality determiner, 81A, 81B...DC voltage calculator, 100A, 100B...Monitoring device. Agent Patent Attorney Kensuke Norichika
Claims (1)
器が逆変換器として動作する変換器の直流電圧を監視す
る監視装置において、前記変換器の直流電圧を検出する
直流電圧検出器と、この直流電圧検出器の出力をある一
定周期毎に読み込み、１回前の読み込み値と、現在の読
み込み値を比較する直流電圧比較手段と、前記交換器の
直流電流を検出する直流電流検出器と、前記変換器の交
流電圧を検出する交流電圧検出器と、直流電流検出器の
出力値と、交流電圧検出器の出力値をある一定周期毎に
読み込み、計算により直流電圧値を求める直流電圧算出
手段と、１回前の直流電圧算出値と現在の算出値を比較
する直流電圧算出値比較手段と、前記直流電圧比較手段
の現在の読み込み値と、前記直流電圧算出手段の現在の
算出値を比較する電圧比較手段を具備し、 前記電圧比較手段が不一致検出し、且つ前記直流電圧比
較手段が不一致検出し、且つ、前記直流電圧算出値比較
手段が一致検出した場合、直流電圧検出器の異常を判断
することを特徴とする監視装置。[Claims] In a monitoring device that monitors the DC voltage of a converter when one converter operates as a forward converter and the other converter operates as an inverse converter, the DC voltage of the converter is detected. a DC voltage detector that reads the output of the DC voltage detector at certain regular intervals and compares the previous read value with the current read value; A DC current detector to detect the AC voltage of the converter, an AC voltage detector to detect the AC voltage of the converter, an output value of the DC current detector, and an output value of the AC voltage detector are read at a certain period, and the DC voltage is determined by calculation. A DC voltage calculation means for calculating a voltage value, a DC voltage calculation value comparison means for comparing a previous DC voltage calculation value and a current calculation value, a current read value of the DC voltage comparison means, and the DC voltage calculation comprising voltage comparison means for comparing current calculated values of the means, when the voltage comparison means detects a mismatch, the DC voltage comparison means detects a mismatch, and the DC voltage calculated value comparison means detects a match; , a monitoring device characterized by determining an abnormality in a DC voltage detector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2241205A JP2801758B2 (en) | 1990-09-13 | 1990-09-13 | Monitoring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2241205A JP2801758B2 (en) | 1990-09-13 | 1990-09-13 | Monitoring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04217816A true JPH04217816A (en) | 1992-08-07 |
| JP2801758B2 JP2801758B2 (en) | 1998-09-21 |
Family
ID=17070768
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2241205A Expired - Lifetime JP2801758B2 (en) | 1990-09-13 | 1990-09-13 | Monitoring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2801758B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2286509A4 (en) * | 2008-05-08 | 2015-04-29 | Trw Automotive Us Llc | Position sensorless motor control |
| JP2015159654A (en) * | 2014-02-24 | 2015-09-03 | 三菱電機株式会社 | Electric power facility supervisory controller and electric power facility supervisory control system |
| US11081879B2 (en) | 2015-10-06 | 2021-08-03 | General Electric Technology Gmbh | Direct current distance protection controllers |
-
1990
- 1990-09-13 JP JP2241205A patent/JP2801758B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2286509A4 (en) * | 2008-05-08 | 2015-04-29 | Trw Automotive Us Llc | Position sensorless motor control |
| JP2015159654A (en) * | 2014-02-24 | 2015-09-03 | 三菱電機株式会社 | Electric power facility supervisory controller and electric power facility supervisory control system |
| US11081879B2 (en) | 2015-10-06 | 2021-08-03 | General Electric Technology Gmbh | Direct current distance protection controllers |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2801758B2 (en) | 1998-09-21 |
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