JP2003502990A - Grounding accident protection system for windings of electrical equipment - Google Patents
Grounding accident protection system for windings of electrical equipmentInfo
- Publication number
- JP2003502990A JP2003502990A JP2001504056A JP2001504056A JP2003502990A JP 2003502990 A JP2003502990 A JP 2003502990A JP 2001504056 A JP2001504056 A JP 2001504056A JP 2001504056 A JP2001504056 A JP 2001504056A JP 2003502990 A JP2003502990 A JP 2003502990A
- Authority
- JP
- Japan
- Prior art keywords
- winding
- voltage transformer
- ground fault
- phase voltage
- generator
- 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.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/06—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric generators; for synchronous capacitors
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/16—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to fault current to earth, frame or mass
- H02H3/17—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to fault current to earth, frame or mass by means of an auxiliary voltage injected into the installation to be protected
Abstract
(57)【要約】 本発明の目的は、電気機器の巻線の接地事故保護システム、特に、変圧器と直列に接続、又は発電機と並列に接続、又は母線に直接接続された機器の作動中に適用可能な、第１電圧変圧器を通って接地された中性点を有する発電機の固定子の巻線である。本発明によるシステムは、第２の電圧変圧器（８）の１次巻線、機器（１）の巻線の中性点（２）に接地された第１の単相電圧変圧器（５）の２次巻線、及び低抵抗抵抗器（７）により形成された回路において、分路リアクトル（６）が電圧変圧器（８）の１次巻線に並列に接続されることを特徴とする。 (57) [Summary] The object of the present invention is to provide a protective system for grounding accidents in windings of electrical equipment, particularly the operation of equipment connected in series with a transformer, or connected in parallel with a generator, or directly connected to a bus. Applicable therein is a stator winding of a generator having a neutral point grounded through a first voltage transformer. The system according to the invention comprises a primary winding of a second voltage transformer (8), a first single-phase voltage transformer (5) grounded to the neutral point (2) of the winding of the device (1). Wherein the shunt reactor (6) is connected in parallel to the primary winding of the voltage transformer (8) in a circuit formed by the secondary winding of (1) and the low-resistance resistor (7). .
Description
【０００１】
（本発明の背景）
本発明の目的は、電圧変圧器を通って接地された中性点を有する電気機器の巻
線の接地故障保護システムであり、特に、変圧器と直列に接続、又は別の発電機
と並列に接続、又は母線に直接接続される機器の作動中に適用可能な、発電機の
固定子の巻線のためのものである。BACKGROUND OF THE INVENTION An object of the present invention is a ground fault protection system for windings of electrical equipment having a neutral point grounded through a voltage transformer, and in particular connected in series with the transformer. , Or in parallel with another generator, or during operation of equipment connected directly to the busbar, for the stator windings of the generator.
【０００２】
（背景技術の説明）
電圧発電機を通って接地される中性点を有する発電機の固定子の巻線の公知な
接地故障保護システムは、１９９５年１１月に発行されたＡＢＢネットワークパ
ートナーのカタログNo.1MDB02012-ENの第３頁の図６に表わされている。その表
わされたシステムは、発電機の中性点と接地の間に接続された単相電圧変圧器を
組込みんでいる。この変圧器の２次巻線には、低抵抗の抵抗器とその抵抗器より
約４倍高い抵抗を有する抵抗器とがお互いに直列に接続された２つの抵抗器が並
列に接続されている。発電機の定格周波数の約１／４に等しい周波数の電源を含
むシステムは低抵抗の抵抗器に並列に接続されている。このシステムは接地故障
保護装置に並列に結合されている。２次巻線が接地故障保護装置の入力に並列に
接続されている単相電圧変圧器は、第１抵抗器の約４倍の高さの抵抗を有する抵
抗器に並列に接続されている。2. Description of the Background Art A known ground fault protection system for a stator winding of a generator having a neutral point grounded through a voltage generator is known from the ABB network published in November 1995. It is represented in FIG. 6 on page 3 of partner catalog No. 1 MDB02012-EN. The represented system incorporates a single-phase voltage transformer connected between the generator neutral and ground. The secondary winding of this transformer is connected in parallel with two resistors in which a low resistance resistor and a resistor having a resistance about four times higher than that resistor are connected in series with each other. . A system including a power supply with a frequency equal to about 1/4 of the generator's rated frequency is connected in parallel with a low resistance resistor. This system is coupled in parallel with the ground fault protection device. A single-phase voltage transformer whose secondary winding is connected in parallel with the input of the ground fault protection device is connected in parallel with a resistor having a resistance which is approximately four times as high as the first resistor.
【０００３】
発電機の固定子の巻線の説明された接地事故保護システムの不利益は、発電機
の固定子の巻線の一部分に接地事故があった場合、接地事故の地点で流れる接地
事故の電流値は、主に、発電機の中性点と接地の間に接続された単相電圧変圧器
の２次側に接続された抵抗器の抵抗値に依存することである。これらの抵抗器は
、常に、接地事故の値の増加を引き起こし、接地事故の場所でのこの電流値が、
常にたいてい、５Ａを超えるようになっている。発電機の固定子の巻線で接地事
故が起きた場合、この電流は固定子にかなりの損害を引き起こす。説明された発
電機の固定子の巻線の接地事故保護システムの別の不利益は、５Ａを超える接地
事故電流値がこの接地事故保護システムにより保護される領域の長さを制限する
ことである。The disadvantage of the described ground fault protection system of the generator stator windings is that if there is a ground fault in a part of the generator stator winding, the ground fault that flows at the ground fault point. The current value of is mainly dependent on the resistance value of the resistor connected to the secondary side of the single-phase voltage transformer connected between the neutral point of the generator and the ground. These resistors always cause an increase in the value of the ground fault, this current value at the location of the ground fault is
It usually exceeds 5A. If a ground fault occurs in the generator stator windings, this current will cause considerable damage to the stator. Another disadvantage of the described generator stator winding ground fault protection system is that ground fault current values above 5 A limit the length of the area protected by this ground fault protection system. .
【０００４】
接地事故保護システムが接地された１次巻線を単相電圧変圧器に組込み、変圧
器が巻線の中性点に接続され、低抵抗の抵抗器がこの変圧器の２次巻線に接続さ
れ、抵抗器が機器の定格周波数の１／４に等しい周波数の電源に並列に接続され
、入力が別の単相電圧変圧器の２次巻線に接続される接地事故保護装置にこの電
源が接続され、この単相電圧変圧器の１次巻線が巻線の中性点に接続された単相
電圧変圧器の２次巻線に並列に接続された、本発明による、電気機器の巻線、特
に、発電機の固定子の巻線のための接地事故保護システムの本質は、第２の単相
電圧変圧器の１次巻線、巻線の中性点に接地された単相電圧変圧器の２次巻線、
及び低抵抗の抵抗器により形成された回路において、分路リアクトルが第２の電
圧変圧器の１次巻線に並列に接続されていることである。分路リアクトルのイン
ダクタンスは０．０１〜２ミリヘンリー内である。A ground fault protection system incorporates a grounded primary winding into a single-phase voltage transformer, the transformer is connected to the neutral point of the winding, and a low resistance resistor is the secondary winding of this transformer. To a ground fault protection device, which is connected to the line, the resistor is connected in parallel to a power supply with a frequency equal to 1/4 of the rated frequency of the device, and the input is connected to the secondary winding of another single-phase voltage transformer According to the invention, the power supply is connected and the primary winding of the single-phase voltage transformer is connected in parallel with the secondary winding of the single-phase voltage transformer connected to the neutral point of the winding. The essence of the ground fault protection system for equipment windings, especially for generator stator windings, is the primary winding of the second single-phase voltage transformer, grounded to the neutral point of the winding Secondary winding of single-phase voltage transformer,
And in the circuit formed by the low resistance resistor, the shunt reactor is connected in parallel with the primary winding of the second voltage transformer. The inductance of the shunt reactor is within 0.01-2 millihenries.
【０００５】
本発明の目的は、直列に接続された変圧器を有する装置で作動する発電機の固
定子の巻線の接地事故保護システムの装置図を示す図面において、実施例として
説明されている。The object of the invention is illustrated by way of example in the drawing showing a device diagram of a ground fault protection system for the stator windings of a generator operating in a device with a transformer connected in series. .
【０００６】
（好適な実施例の説明）
中性点２を有する発電機１は、母線４を通って変圧器３に接続されている。発
電機の中性点２と接地との間には、１次巻線が接地された単相電圧変圧器５が接
続されている。この変圧器の２次巻線には、数百オームの低抵抗の抵抗器７に直
接に接続された分路リアクトル６が並列に接続されている。分路リアクトル６は
２次巻線が接地事故保護装置９に並列に接続された単相電圧変圧器８の１次巻線
に並列に接続されている。抵抗器７は発電機１の定格周波数の１／４に等しい周
波数の電源に並列に接続され、それは注入システム１０である。このシステムは
接地事故保護装置９に並列に結合されている。Description of the Preferred Embodiment A generator 1 having a neutral point 2 is connected to a transformer 3 via a bus bar 4. A single-phase voltage transformer 5 whose primary winding is grounded is connected between the neutral point 2 of the generator and the ground. The secondary winding of this transformer is connected in parallel with a shunt reactor 6 which is directly connected to a low resistance resistor 7 of several hundred ohms. The shunt reactor 6 is connected in parallel with the primary winding of a single-phase voltage transformer 8 whose secondary winding is connected in parallel with the ground fault protection device 9. The resistor 7 is connected in parallel to a power supply with a frequency equal to 1/4 of the rated frequency of the generator 1, which is the injection system 10. This system is connected in parallel to the ground protection device 9.
【０００７】
注入システム１０により注入された電圧は、発電機の周波数と異なる周波数を
有し、接地に関して機器の導体をバイアスするのに役立つ。接地事故は事故の性
質及び注入電圧に依存する電流を発生させる。接地事故保護装置９はこの電流及
び注入電圧を監視し、事故が発生しているかどうか、及び事故の本質は何かを決
定する。必要な場合、接地事故保護装置９は発電機の接続を断つための遮断器を
作動させる。The voltage injected by the injection system 10 has a frequency different from that of the generator and serves to bias the conductors of the equipment with respect to ground. A ground fault produces a current that depends on the nature of the fault and the injection voltage. The ground fault protection device 9 monitors this current and the injected voltage to determine if a fault has occurred and what the fault is. If necessary, the ground fault protection device 9 activates a circuit breaker to disconnect the generator.
【０００８】
変圧器３に接続された発電機１の事故のない動作状態において、接地事故のキ
ャパシタンス電流及び単相電圧変圧器５の２次巻線に接続されたエレメントを通
る電流はゼロに等しい。単相電圧変圧器５の２次巻線に接続された分路リアクト
ル６のインダクタンスは、接地事故の間、発電機１の固定子の巻線の主絶縁体を
通過する電流を５Ａ以下の値に制限するように選択される。分路リアクトル６の
インダクタンスの値は、好ましくは、０．０１〜２ミリヘンリーの範囲内である
。分路リアクトル６のインダクタンスの適切な選択により、発電機１の回転子の
巻線の全長に沿った事故のため、接地事故保護装置９の適切な作動が保証され、
発電機１の固定子の磁気回路に対する損傷を減少させ、まったく排除さえさせる
。In the fault-free operating state of the generator 1 connected to the transformer 3, the capacitance current of the ground fault and the current through the element connected to the secondary winding of the single-phase voltage transformer 5 are equal to zero. . The inductance of the shunt reactor 6 connected to the secondary winding of the single-phase voltage transformer 5 makes the current passing through the main insulator of the stator winding of the generator 1 a value of 5 A or less during a ground fault. Is selected to be restricted to. The value of the inductance of the shunt reactor 6 is preferably in the range of 0.01 to 2 millihenries. Proper selection of the inductance of the shunt reactor 6 ensures the proper operation of the ground fault protection device 9 for accidents along the entire length of the rotor winding of the generator 1.
Damage to the magnetic circuit of the stator of the generator 1 is reduced, even eliminated altogether.
【０００９】
本発明は、発電機だけでなく、電動機又は変圧器のような別のタイプの電気機
器を保護するのにも使用可能である。The invention can be used to protect not only generators, but also other types of electrical equipment such as electric motors or transformers.
───────────────────────────────────────────────────── フロントページの続き (81)指定国 ＥＰ(ＡＴ，ＢＥ，ＣＨ，ＣＹ， ＤＥ，ＤＫ，ＥＳ，ＦＩ，ＦＲ，ＧＢ，ＧＲ，ＩＥ，Ｉ Ｔ，ＬＵ，ＭＣ，ＮＬ，ＰＴ，ＳＥ)，ＯＡ(ＢＦ，ＢＪ ，ＣＦ，ＣＧ，ＣＩ，ＣＭ，ＧＡ，ＧＮ，ＧＷ，ＭＬ， ＭＲ，ＮＥ，ＳＮ，ＴＤ，ＴＧ)，ＡＰ(ＧＨ，ＧＭ，Ｋ Ｅ，ＬＳ，ＭＷ，ＭＺ，ＳＤ，ＳＬ，ＳＺ，ＴＺ，ＵＧ ，ＺＷ)，ＥＡ(ＡＭ，ＡＺ，ＢＹ，ＫＧ，ＫＺ，ＭＤ， ＲＵ，ＴＪ，ＴＭ)，ＡＥ，ＡＧ，ＡＬ，ＡＭ，ＡＴ， ＡＵ，ＡＺ，ＢＡ，ＢＢ，ＢＧ，ＢＲ，ＢＹ，ＣＡ，Ｃ Ｈ，ＣＮ，ＣＲ，ＣＵ，ＣＺ，ＤＥ，ＤＫ，ＤＭ，ＤＺ ，ＥＥ，ＥＳ，ＦＩ，ＧＢ，ＧＤ，ＧＥ，ＧＨ，ＧＭ， ＨＲ，ＨＵ，ＩＤ，ＩＬ，ＩＮ，ＩＳ，ＪＰ，ＫＥ，Ｋ Ｇ，ＫＰ，ＫＲ，ＫＺ，ＬＣ，ＬＫ，ＬＲ，ＬＳ，ＬＴ ，ＬＵ，ＬＶ，ＭＡ，ＭＤ，ＭＧ，ＭＫ，ＭＮ，ＭＷ， ＭＸ，ＭＺ，ＮＯ，ＮＺ，ＰＬ，ＰＴ，ＲＯ，ＲＵ，Ｓ Ｄ，ＳＥ，ＳＧ，ＳＩ，ＳＫ，ＳＬ，ＴＪ，ＴＭ，ＴＲ ，ＴＴ，ＴＺ，ＵＡ，ＵＧ，ＵＳ，ＵＺ，ＶＮ，ＹＵ， ＺＡ，ＺＷ (72)発明者 プフィッフネール ミッシェル スイス ツェーハー8906 ボンステッテン ヘレンホルスヴェグ 53 Ｆターム(参考） 5G044 AA03 AE01 CA04 5G058 BB02 BC05 BC16 BD10 ─────────────────────────────────────────────────── ─── Continued front page (81) Designated countries EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE), OA (BF, BJ , CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, K E, LS, MW, MZ, SD, SL, SZ, TZ, UG , ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AG, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, C H, CN, CR, CU, CZ, DE, DK, DM, DZ , EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, K G, KP, KR, KZ, LC, LK, LR, LS, LT , LU, LV, MA, MD, MG, MK, MN, MW, MX, MZ, NO, NZ, PL, PT, RO, RU, S D, SE, SG, SI, SK, SL, TJ, TM, TR , TT, TZ, UA, UG, US, UZ, VN, YU, ZA, ZW (72) Inventor Pfiffner Michel Swiss Zeher 8906 Bonstatten Helen Holsveg 53 F-term (reference) 5G044 AA03 AE01 CA04 5G058 BB02 BC05 BC16 BD10
Claims (3)
を組込み、その２次巻線に低抵抗の抵抗器が接続され、抵抗器は機器の定格周波
数の１／４に等しい周波数の電源に並列に接続され、この電源は入力が第２の単
相電圧変圧器の２次巻線に接続される接地事故保護装置と接続され、この第２の
電圧変圧器の１次巻線が前記巻線の中性点に接続された前記第１の単相電圧変圧
器の２次巻線と接続され、前記第２の単相電圧変圧器８の１次巻線、前記機器１
の巻線の中性点２に設置された前記第１の単相電圧変圧器５の２次巻線、及び低
抵抗の抵抗器７により形成された回路において、分路リアクトル６が前記電圧変
圧器８の１次巻線と並列に接続されていることを特徴とする電気機器の巻線の接
地事故保護システム。1. A grounded first single-phase voltage transformer connected to a neutral point of a winding is incorporated, and a low resistance resistor is connected to its secondary winding, and the resistor is a device rating. It is connected in parallel to a power supply with a frequency equal to 1/4 of the frequency, this power supply being connected to a ground fault protection device whose input is connected to the secondary winding of a second single-phase voltage transformer, The primary winding of the voltage transformer is connected to the secondary winding of the first single-phase voltage transformer connected to the neutral point of the winding, and the first winding of the second single-phase voltage transformer 8 is connected. Next winding, the device 1
In the circuit formed by the secondary winding of the first single-phase voltage transformer 5 installed at the neutral point 2 of the winding and the low resistance resistor 7, the shunt reactor 6 is the voltage transformer. A ground fault protection system for a winding of an electric device, which is connected in parallel with the primary winding of the device 8.
リヘンリーの範囲内にある請求項１に記載の電気機器の巻線の接地事故保護シス
テム。2. A ground fault protection system for electrical equipment windings according to claim 1, wherein the inductance of said shunt reactor 6 is in the range of 0.01 to 2 millihenries.
に記載の電気機器の巻線の接地事故保護システム。3. The electric device is a generator, an electric motor or a transformer.
A grounding accident protection system for windings of electrical equipment as described in.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PL333713 | 1999-06-11 | ||
| PL33371399A PL333713A1 (en) | 1999-06-11 | 1999-06-11 | Earth-fault protection circuit for a generator stator winding |
| PCT/CH2000/000298 WO2000077906A1 (en) | 1999-06-11 | 2000-05-25 | An electrical machine winding ground-fault protection system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2003502990A true JP2003502990A (en) | 2003-01-21 |
Family
ID=20074562
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001504056A Pending JP2003502990A (en) | 1999-06-11 | 2000-05-25 | Grounding accident protection system for windings of electrical equipment |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP1188211A1 (en) |
| JP (1) | JP2003502990A (en) |
| CN (1) | CN1355952A (en) |
| AU (1) | AU4532300A (en) |
| PL (1) | PL333713A1 (en) |
| WO (1) | WO2000077906A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1890369B1 (en) * | 2006-08-18 | 2013-10-02 | ABB Research Ltd | Ground fault detection |
| RU2542494C2 (en) * | 2010-07-19 | 2015-02-20 | Абб Текнолоджи Аг | Device and method for detection of ground short-circuit |
| CN104111371A (en) * | 2014-07-22 | 2014-10-22 | 中国神华能源股份有限公司 | Generator vertical zero sequence voltage acquiring method and vertical zero sequence inter-turn protection method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4329382A1 (en) * | 1993-09-01 | 1995-03-02 | Abb Management Ag | Method and device for detecting earth faults on the conductors of an electrical machine |
-
1999
- 1999-06-11 PL PL33371399A patent/PL333713A1/en not_active IP Right Cessation
-
2000
- 2000-05-25 CN CN 00808738 patent/CN1355952A/en active Pending
- 2000-05-25 AU AU45323/00A patent/AU4532300A/en not_active Abandoned
- 2000-05-25 WO PCT/CH2000/000298 patent/WO2000077906A1/en not_active Application Discontinuation
- 2000-05-25 JP JP2001504056A patent/JP2003502990A/en active Pending
- 2000-05-25 EP EP00926625A patent/EP1188211A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| PL333713A1 (en) | 2000-12-18 |
| AU4532300A (en) | 2001-01-02 |
| EP1188211A1 (en) | 2002-03-20 |
| CN1355952A (en) | 2002-06-26 |
| WO2000077906A1 (en) | 2000-12-21 |
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