JPH0746642B2 - Temperature monitoring device for neutral point ground resistance device - Google Patents
Temperature monitoring device for neutral point ground resistance deviceInfo
- Publication number
- JPH0746642B2 JPH0746642B2 JP60015973A JP1597385A JPH0746642B2 JP H0746642 B2 JPH0746642 B2 JP H0746642B2 JP 60015973 A JP60015973 A JP 60015973A JP 1597385 A JP1597385 A JP 1597385A JP H0746642 B2 JPH0746642 B2 JP H0746642B2
- Authority
- JP
- Japan
- Prior art keywords
- neutral point
- resistance device
- voltage
- current
- resistance value
- 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 - Lifetime
Links
Landscapes
- Amplifiers (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Apparatuses And Processes For Manufacturing Resistors (AREA)
- Measurement Of Resistance Or Impedance (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Description
【発明の詳細な説明】 産業上の利用分野 この発明は、中性点接地抵抗装置の温度監視装置に関す
るものである。Description: TECHNICAL FIELD The present invention relates to a temperature monitoring device for a neutral grounding resistance device.
従来の技術 従来、変圧器の中性点と接地点との間に中性点接地抵抗
装置を設けたものがあった。2. Description of the Related Art Conventionally, there has been one in which a neutral point ground resistance device is provided between a neutral point of a transformer and a ground point.
発明が解決しようとする問題点 しかしながら、この中性点接地抵抗装置は、送電線の地
絡故障が長時間継続して地絡電流が中性点接地抵抗装置
に定絡時間以上流れた場合、これを検出し保護する装置
が設けられていないため、系統保護の地絡継電器等が動
作しないときには抵抗体が焼損するというケースがあっ
た。また１回の地絡事故が定絡時間内であっても短時間
の間隔で再び地絡事故が起きた場合、やはり温度上昇が
過大となってしまう欠点がある。特に最近のガス密封型
中性点接地抵抗装置においては、抵抗体の焼損以外に容
器の内圧が上昇し、容器の破裂という事故に発展する可
能性もある。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, this neutral point grounding resistance device, when the ground fault of the transmission line continues for a long time and the ground fault current flows to the neutral point grounding resistance device for a fixed time or more, Since there is no device for detecting and protecting this, there are cases in which the resistor burns out when the system protection ground fault relay or the like does not operate. In addition, even if one ground fault occurs within the fixed time, if the ground fault occurs again at short intervals, the temperature rise will be excessive. Particularly in the recent gas-sealed neutral point grounding resistance device, in addition to burning of the resistor, the internal pressure of the container rises, which may lead to an accident of rupture of the container.
すなわち、この発明は、抵抗体を焼損から保護すること
ができる中性点接地抵抗装置の温度監視装置を提供する
ものである。That is, the present invention provides a temperature monitoring device for a neutral grounding resistance device capable of protecting a resistor from being burnt out.
問題点を解決するための手段 この発明は、中性点接地抵抗装置と、この中性点接地抵
抗装置に流れる電流を検出する電流検出手段と、前記中
性点接地抵抗装置の両端の電圧を検出する電圧検出手段
と、前記電圧検出手段の電圧と電流検出手段の電流との
比に対応する抵抗値を演算するとともに前記抵抗値がそ
の抵抗体材料の抵抗温度係数より求めた前記中性点接地
抵抗装置の最大許容温度に対応する抵抗値に等しい時動
作する警報装置とを備えたものである。Means for Solving the Problems The present invention relates to a neutral point grounding resistance device, a current detecting means for detecting a current flowing through the neutral point grounding resistance device, and a voltage across the neutral point grounding resistance device. The neutral point obtained by calculating the resistance value corresponding to the ratio of the voltage of the voltage detection means and the voltage of the voltage detection means and the current of the current detection means, and the resistance value obtained from the resistance temperature coefficient of the resistor material. And an alarm device that operates when the resistance value is equal to the maximum allowable temperature of the ground resistance device.
作用 中性点接地抵抗装置の抵抗材料の抵抗温度係数をあらか
じめ測定することにより、中性点接地抵抗装置の最大許
容温度である規定温度に対応する抵抗値である基準抵抗
値を決定することができる。そこで電圧，電流検出手段
により得られた値から警報装置において抵抗値を演算
し、基準抵抗値と等しいとき警報信号を出力することに
より、中性点接地抵抗装置の焼損防止等の保護が図れ
る。By measuring the temperature coefficient of resistance of the resistance material of the neutral grounding resistance device in advance, it is possible to determine the reference resistance value, which is the resistance value corresponding to the specified temperature, which is the maximum allowable temperature of the neutral grounding resistance device. it can. Therefore, the resistance value is calculated in the alarm device from the values obtained by the voltage / current detection means, and an alarm signal is output when the resistance value is equal to the reference resistance value, whereby protection such as burnout prevention of the neutral grounding resistance device can be achieved.
実施例 この発明の一実施例を図面に基づいて説明する。すなわ
ち、変圧器１の非有効接地系統用の中性点端子1aに切離
し用断路器２を介して中性点接地抵抗装置３の一端が接
続され、その他端が接地される。電流検出手段４は中性
点の電流を検出する変流器で構成され、この変流器は常
時の小電流（残留電流）から定格電流までの範囲を正確
に測定できる、たとえばパーマロイ等を使用したダイナ
ミックレンジの広いものが好ましい。電圧検出手段５は
中性点接地抵抗装置３の両端すなわち中性点の電圧を検
出する電圧変成器で構成され、この電圧変成器としては
計器用変圧器、またはコンデンサ分圧器が適し、またガ
ス密封型の中性点接点抵抗装置ではアンプPD（増幅型の
コンデンサ型計器用変圧器）等の適用が考えられる。警
報装置６は電流検出手段４および電圧検出手段５の電流
および電圧より中性点接地抵抗装置３のインピーダンス
（抵抗値）を演算するとともに、最大許容温度である規
定温度に対応する抵抗値である基準抵抗値となった場合
に断路器２等による系統の切り離し等の指令が出せるイ
ンピーダンスリレーで構成されている。Embodiment An embodiment of the present invention will be described with reference to the drawings. That is, one end of the neutral point grounding resistance device 3 is connected to the neutral point terminal 1a for the ineffective grounding system of the transformer 1 via the disconnecting switch 2, and the other end is grounded. The current detecting means 4 is composed of a current transformer that detects a current at a neutral point, and this current transformer can accurately measure a range from a small current (residual current) to a rated current at all times, for example, a permalloy or the like is used. A wide dynamic range is preferable. The voltage detecting means 5 is composed of a voltage transformer that detects the voltage at both ends of the neutral point grounding resistance device 3, that is, the neutral point. As this voltage transformer, an instrument transformer or a capacitor voltage divider is suitable. In the sealed neutral point contact resistance device, application of an amplifier PD (amplification type capacitor type instrument transformer) is considered. The alarm device 6 calculates the impedance (resistance value) of the neutral point grounding resistance device 3 from the current and voltage of the current detection means 4 and the voltage detection means 5, and has a resistance value corresponding to a specified temperature which is the maximum allowable temperature. It is composed of an impedance relay that can issue a command such as disconnection of the system by the disconnector 2 etc. when the reference resistance value is reached.
中性点接地抵抗装置３の抵抗体材料の抵抗温度係数は、
たとえば５〜11×10-4／℃であり、その温度上昇値はた
とえば400℃において、 R400＝R0｛１＋（５〜11×10-4）×400｝ ＝（1.2〜1.44）R0 となる。したがって、警報装置６に設定されるべき基準
抵抗値を、中性点接地抵抗装置３が焼損しない温度（規
定温度）に対応して計算することができる。一方電圧検
出器５および電流検出器４の電圧および電流より警報装
置６で中性点接地抵抗装置の実際の抵抗値を演算し、そ
の抵抗値が基準抵抗値以上になると前記警報装置６が動
作するため、その信号により断路器２が切離し動作する
等によって中性点接地抵抗装置３の温度が規定温度以下
に抑えられることとなる。The temperature coefficient of resistance of the resistor material of the neutral grounding resistance device 3 is
For example, it is 5 to 11 × 10 −4 / ° C., and the temperature rise value is 400 ° C., for example, R 400 = R 0 {1+ (5 to 11 × 10 −4 ) × 400} = (1.2 to 1.44) R 0 Becomes Therefore, the reference resistance value to be set in the alarm device 6 can be calculated corresponding to the temperature (specified temperature) at which the neutral grounding resistance device 3 does not burn out. On the other hand, the alarm device 6 calculates the actual resistance value of the neutral grounding resistance device from the voltage and current of the voltage detector 5 and the current detector 4, and the alarm device 6 operates when the resistance value becomes equal to or higher than the reference resistance value. Therefore, the temperature of the neutral point grounding resistance device 3 can be suppressed to a specified temperature or lower due to the disconnection operation of the disconnector 2 caused by the signal.
このように構成したため、中性点接地抵抗装置の温度を
電圧，電流の測定により推定でき、中性点接地抵抗装置
の異常発熱時の保護が可能となる。また系統保護装置
（地絡保護）が故障し、地絡故障が除去できない場合の
後備保護として有用となる。With this configuration, the temperature of the neutral point grounding resistance device can be estimated by measuring the voltage and current, and it is possible to protect the neutral point grounding resistance device during abnormal heat generation. Further, it becomes useful as a back-up protection when the system protection device (ground fault protection) fails and the ground fault cannot be eliminated.
発明の効果 この発明によれば、中性点接地抵抗装置の電流および電
圧を検出し、その抵抗値を演算して抵抗値がその抵抗体
材料の抵抗温度係数より求めた中性点接地抵抗装置の最
大許容温度に対応する抵抗値になったとき、警報指令を
出す構成としたことにより、いかなる地絡事故に対して
も中性点接地抵抗装置の焼損その他の事故を防止でき、
中性点接地抵抗装置の保護を確実に図ることができると
いう効果がある。EFFECTS OF THE INVENTION According to the present invention, the neutral point grounding resistance device in which the current and the voltage of the neutral point grounding resistance device are detected, the resistance value is calculated, and the resistance value is obtained from the resistance temperature coefficient of the resistor material. When a resistance value corresponding to the maximum allowable temperature of is reached, an alarm command can be issued to prevent burnout of the neutral grounding resistance device and other accidents against any ground fault.
There is an effect that the neutral grounding resistance device can be surely protected.
図面はこの発明の一実施例の回路図である。 ３…中性点接地抵抗装置、４…電流検出手段、５…電圧
検出手段、６…警報装置The drawing is a circuit diagram of an embodiment of the present invention. 3 ... Neutral grounding resistance device, 4 ... Current detecting means, 5 ... Voltage detecting means, 6 ... Alarm device
Claims (1)
抗装置に流れる電流を検出する電流検出手段と、前記中
性点接地抵抗装置の両端の電圧を検出する電圧検出手段
と、前記電圧検出手段の電圧と電流検出手段の電流との
比に対応する抵抗値を演算するとともに前記抵抗値がそ
の抵抗体材料の抵抗温度係数より求めた前記中性点接地
抵抗装置の最大許容温度に対応する抵抗値に等しい時動
作する警報装置とを備えた中性点接地抵抗装置の温度監
視装置。1. A neutral grounding resistance device, a current detecting means for detecting a current flowing through the neutral grounding resistance device, and a voltage detecting means for detecting a voltage across the neutral grounding resistance device. The maximum allowable temperature of the neutral grounding resistance device is obtained by calculating the resistance value corresponding to the ratio of the voltage of the voltage detection means and the current of the current detection means, and the resistance value is obtained from the resistance temperature coefficient of the resistor material. And a warning device that operates when the resistance value is equal to the resistance value of the neutral point ground resistance device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60015973A JPH0746642B2 (en) | 1985-01-29 | 1985-01-29 | Temperature monitoring device for neutral point ground resistance device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60015973A JPH0746642B2 (en) | 1985-01-29 | 1985-01-29 | Temperature monitoring device for neutral point ground resistance device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61174603A JPS61174603A (en) | 1986-08-06 |
| JPH0746642B2 true JPH0746642B2 (en) | 1995-05-17 |
Family
ID=11903649
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60015973A Expired - Lifetime JPH0746642B2 (en) | 1985-01-29 | 1985-01-29 | Temperature monitoring device for neutral point ground resistance device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0746642B2 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54162149A (en) * | 1978-06-14 | 1979-12-22 | Hitachi Ltd | Neutral grounding monitor of generator |
-
1985
- 1985-01-29 JP JP60015973A patent/JPH0746642B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61174603A (en) | 1986-08-06 |
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