CN106655098A - Stator grounding protection method used in grid-connection operation of nuclear power unit - Google Patents
Stator grounding protection method used in grid-connection operation of nuclear power unit Download PDFInfo
- Publication number
- CN106655098A CN106655098A CN201611256014.5A CN201611256014A CN106655098A CN 106655098 A CN106655098 A CN 106655098A CN 201611256014 A CN201611256014 A CN 201611256014A CN 106655098 A CN106655098 A CN 106655098A
- Authority
- CN
- China
- Prior art keywords
- nuclear power
- zero
- stator
- generator
- power generating
- 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
- H02H7/062—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 for parallel connected generators
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
For certain large-scale nuclear power units, a condition that nuclear power stations are in long-term inverse-power-transmission operating condition is taken into consideration; for limiting grounding re-striking arc overvoltage in the operating mode, a low voltage side of a main transformer is mostly grounded through a power distribution transformer; a secondary side is connected with a resistor in parallel; and a neutral point of a generator is grounded through a grounding transformer, so that two grounding points are formed. The invention provides a stator grounding protection method used in a grid-connection operation of a nuclear power unit; according to the method, differential protection is performed by zero-sequence currents on a generator terminal and a neutral point side of the nuclear power unit, so that influence from line breaking of a voltage transformer can be avoided; rapid and sensitive actions can be realized; and adverse conditions in the situation of the stator grounding protection of the existing generator unit can be avoided.
Description
Technical field
The present invention relates to earthing protection method for stator when a kind of nuclear power generating sets are incorporated into the power networks, belongs to Automation of Electric Systems
Control field.
Background technology
Nuclear power generating sets have single-machine capacity big, involve great expense, and it requires that relay protection is sensitive and rapidly cut off failure, with
Ensure the safe and stable operation of nuclear power generating sets.According to GB GB 14285-2006《Relay protection and automatic safety device technology are advised
Journey》Regulation, " when digital protecting is set for the generator transformer assembling of 100 MW and above capacity, in addition to non-ionizing energy loss,
Answer duplicate system retrofit ".The generator protection configured using dual principle, the general A sets configuration subharmonic of zero-sequence fundamental voltage+3
Residual voltage principle stator ground fault protection, B set configuration injected type stator ground protections.
It is to limit this operation for some large nuclear-power units, it is contemplated that nuclear power station has the long-term operating mode of falling transmission operation
Arc overvoltage of restriking is grounded under mode, many Jing distribution of main transformer low-pressure side become ground connection, and secondary is parallel with resistance, along with generator
Property point it is grounded become ground connection just have 2 earth points, such as Zhejiang Fan family mountain, Fujian Fuqing nuclear power station, concrete primary connection such as Fig. 1 institutes
Show.
Before and after nuclear power generating sets are incorporated into the power networks, the resistance value that injected type stator ground protection is detected be it is different, it is grid-connected
Before detect is stator winding resistance to earth value, and it is grid-connected after detect is stator winding resistance to earth value and main transformer low pressure
The parallel value of side earth resistance.Secondly, grid-connected rear injected type stator ground protection is in addition to the 20 Hz signals for experiencing injection,
50 Hz and 150 Hz signals that also engine block is produced.As certain 1000 M W level nuclear power generating sets that following document is mentioned exist
Before and after grid-connected, there is significantly skew in injection low frequency signal phase angle, and grid-connected front phase angle is 270 degree, grid-connected rear phase angle mutation to 280
Degree, causes resistance value under normal circumstances to decline to a great extent, and reduces the measurement range of earth resistance, affects the normal operation of protection.
Chen Jiasheng, Zhang Qixue, Guo Zigang etc. nuclear power generating sets injected type stator ground protection discussion on some issues [J],
2016,10:172-175。
The content of the invention
In order to solve the deficiencies in the prior art, it is an object of the invention to provide a kind of nuclear power generating sets simultaneously according to background above
Earthing protection method for stator during network operation, the method adopts power frequency Zero sequence current differential protection, with quick, sensitive spy
Point.
The technical scheme that earthing protection method for stator when a kind of nuclear power generating sets of the present invention are incorporated into the power networks is adopted：It is grid-connected normal
There is no zero-sequence fault source on operation generator unit stator, so zero sequence difference stream will not be produced；If after grid-connected on generator unit stator
Generation single-point grounding failure, can produce zero sequence difference stream, it is possible to adopt in the nuclear power generating sets primary system shown in Fig. 1
Zero sequence current differential protection.
Further technical scheme of the invention：Zero sequence current differential protection is as follows using criterion：
（1）
WhereinZero sequence current differential protection electric current is represented,Zero-sequence current stalling current is represented, k represents restraint coefficient,
Zero-sequence current difference stream initiation value.
Further technical scheme of the invention：Formula（1）In difference current and stalling current computational methods it is as follows
（2）
WhereinGenerator generator terminal zero-sequence current is represented,Represent generator centerline zero-sequence current.
The present invention has compared with prior art following features：
2 earth points of the nuclear power generating sets in normal operation are made full use of, occur to produce zero-sequence fault source after generator unit ground connection,
Earthing protection method for stator when a kind of nuclear power generating sets now proposed by the present invention are incorporated into the power networks utilizes Zero sequence current differential protection,
To not be affected by voltage transformer disconnection, can enzyme rapidly and sensitively action, it is to avoid existing Stator ground protection exists
Rough sledding under this situation.
Description of the drawings
The specific embodiment of the present invention is described further below in conjunction with the accompanying drawings：
Fig. 1 nuclear power generating sets primary connection system diagrams；
Fig. 2 nuclear power generating sets Stator ground fault zero-sequence network figures.
Specific embodiment
It is to limit this operation for some large nuclear-power units, it is contemplated that nuclear power station has the long-term operating mode of falling transmission operation
Arc overvoltage of restriking is grounded under mode, many Jing distribution of main transformer low-pressure side become ground connection, and secondary is parallel with resistance, along with generator
Property point it is grounded become ground connection just have 2 earth points, such as Zhejiang Fan family mountain, Fujian Fuqing nuclear power station, concrete primary connection such as Fig. 1 institutes
Show.
Specific embodiment：When there is stator single-point grounding failure in generating set, nuclear power generating sets Stator ground fault zero sequence
Network such as Fig. 2, n are the no-load voltage ratio of generator neutral point side distribution transformer, and Rn is the resistance value of the distribution transformer low-pressure side,
For residual voltage at earth point, Z0s is earth point equivalent zero sequence impedance to neutral point, and Z0g1 is earth point to generator end
Equivalent zero sequence impedance, Z0g1 is to become equivalent zero sequence impedance at earth point to main transformer low-pressure side Jing distribution at generator end,Represent
Generator generator terminal zero-sequence current,Represent generator centerline zero-sequence current.
Now, earthing protection method for stator when a kind of nuclear power generating sets of the invention are incorporated into the power networks adopts criterion such as formula（1）, weight
Row are as follows：
（1）
WhereinRepresent zero sequence current differential protection electric current；Represent zero-sequence current stalling current；K represents restraint coefficient；Zero
Sequence difference between current stream initiation value, is arranged by out-of-balance current is escaped.
Formula（1）In difference current and stalling current computational methods it is as follows
（2）
WhereinGenerator generator terminal zero-sequence current is represented,Represent generator centerline zero-sequence current.
According to Fig. 2,
（3）
（4）
From formula（5）And formula（6）As can be seen that there is no zero-sequence fault source when being normally incorporated into the power networks, i.e.,For 0, so as to difference stream is zero,
Reliability is failure to actuate；When there is stator single-point grounding, zero sequence current differential protection electric current and zero-sequence current stalling current are numerically close to
It is equal, because restraint coefficient k is less than 1, so quick acting.
The above is only the preferred embodiments of the present invention, for those skilled in the art,
Without departing from the principles of the invention, some improvements and modifications can also be made, these improvements and modifications also should be regarded as this
Bright protection domain.
Claims (3)
1. earthing protection method for stator when a kind of nuclear power generating sets of the invention are incorporated into the power networks, it is characterised in that：According to nuclear power generating sets
Possess 2 earth points during normal operation, so there is no zero-sequence fault source on grid-connected normal operation generator unit stator, so will not produce
Raw zero sequence difference stream；It is to produce in nuclear power generating sets primary system if there is single-point grounding failure on generator unit stator after grid-connected
Raw zero sequence difference stream, so stator ground fault protection when being incorporated into the power networks as nuclear power generating sets using Zero sequence current differential protection.
2. earthing protection method for stator when a kind of nuclear power generating sets for being required according to right 1 are incorporated into the power networks, it is characterised in that zero sequence
Current differential protection is as follows using criterion：
（1）
WhereinZero sequence current differential protection electric current is represented,Zero-sequence current stalling current is represented, k represents restraint coefficient,
Zero-sequence current difference stream initiation value.
3. earthing protection method for stator when a kind of nuclear power generating sets for being required according to right 2 are incorporated into the power networks, it is characterised in that：Formula
（1）In difference current and stalling current computational methods it is as follows
（2）
WhereinGenerator generator terminal zero-sequence current is represented,Represent generator centerline zero-sequence current.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611256014.5A CN106655098A (en) | 2016-12-30 | 2016-12-30 | Stator grounding protection method used in grid-connection operation of nuclear power unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611256014.5A CN106655098A (en) | 2016-12-30 | 2016-12-30 | Stator grounding protection method used in grid-connection operation of nuclear power unit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106655098A true CN106655098A (en) | 2017-05-10 |
Family
ID=58837842
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611256014.5A Pending CN106655098A (en) | 2016-12-30 | 2016-12-30 | Stator grounding protection method used in grid-connection operation of nuclear power unit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106655098A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003500995A (en) * | 1999-05-24 | 2003-01-07 | エービービー パワー オートメーション アクチェンゲゼルシャフト | Grounding accident protection system for windings of electrical equipment |
| CN1411116A (en) * | 2002-11-29 | 2003-04-16 | 清华大学 | Generator stator single phase grounding protection method |
| CN101071152A (en) * | 2007-06-14 | 2007-11-14 | 上海交通大学 | Method for detecting generator stator single-phase earthing fault direction |
| CN101295870A (en) * | 2007-04-24 | 2008-10-29 | 许继集团有限公司 | Method for discriminating generator stator single-phase ground fault by fundamental wave zero sequence excess current |
| US20080284385A1 (en) * | 2007-05-17 | 2008-11-20 | Gm Global Technology Operations, Inc. | High efficiency generator |
| US20090160454A1 (en) * | 2006-08-18 | 2009-06-25 | Johansson Stefan G | Ground Fault Detection |
-
2016
- 2016-12-30 CN CN201611256014.5A patent/CN106655098A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003500995A (en) * | 1999-05-24 | 2003-01-07 | エービービー パワー オートメーション アクチェンゲゼルシャフト | Grounding accident protection system for windings of electrical equipment |
| CN1411116A (en) * | 2002-11-29 | 2003-04-16 | 清华大学 | Generator stator single phase grounding protection method |
| US20090160454A1 (en) * | 2006-08-18 | 2009-06-25 | Johansson Stefan G | Ground Fault Detection |
| CN101295870A (en) * | 2007-04-24 | 2008-10-29 | 许继集团有限公司 | Method for discriminating generator stator single-phase ground fault by fundamental wave zero sequence excess current |
| US20080284385A1 (en) * | 2007-05-17 | 2008-11-20 | Gm Global Technology Operations, Inc. | High efficiency generator |
| CN101071152A (en) * | 2007-06-14 | 2007-11-14 | 上海交通大学 | Method for detecting generator stator single-phase earthing fault direction |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3605768B1 (en) | Safe processing method for active voltage reduction of ground fault phase of non-effective grounding system | |
| CN105140897B (en) | A kind of guard method suitable for small resistance grounding system singlephase earth fault | |
| CN108594071B (en) | Single-phase earth fault detection method for neutral point small-resistance earth distribution network | |
| EP2128951B1 (en) | Electronic active earthing system for use in high-voltage distribution networks | |
| CN103474980B (en) | A kind of power distribution network single-phase ground protection method based on transient power direction | |
| CN110021918B (en) | Single-phase short-circuit protection method for resistance-grounded power distribution network based on zero-sequence current ratio | |
| CN103208788A (en) | Intelligent dynamic power distribution network neutral-point grounding method and complete device | |
| CN103474974B (en) | A kind of distribution network single-phase ground protection method based on zero-sequence current Sudden Changing Rate fitting a straight line direction | |
| CN108872791B (en) | The single-phase high-impedance of low resistance grounding power distribution network identifies and guard method | |
| CN101719660B (en) | Method for automatically resetting grounding protection device of small-current system | |
| CN107315128A (en) | A kind of distributed earthing wire-selecting method and system based on GOOSE | |
| CN103364692A (en) | Single-phase earth fault line selection method of power distribution network earthing system | |
| CN105098748A (en) | Surge protector and method for enhancing temporary overvoltage endurance thereof | |
| CN106959403B (en) | A kind of distributed generation resource access distribution net work earthing fault detection method | |
| CN108879645A (en) | A kind of arc suppression coil and pro-active intervention arc-extinction device paired running device and method | |
| CN105162086B (en) | Guard method for the grid-connected transformer grounding system of DG | |
| CN104078936B (en) | Injection type stator ground protection method adapting to pump storage group variable frequency starting | |
| Deshmukh et al. | Analysis of distance protection performance for line employing UPFC | |
| CN106655098A (en) | Stator grounding protection method used in grid-connection operation of nuclear power unit | |
| CN101348085B (en) | Electric railway feeder line impedance protecting method based on power supply section differential pressure and leading-phase current | |
| CN113949049B (en) | Self-adaptive single-phase reclosing method for 220kV power transmission line | |
| CN103490384B (en) | Multi-generator ship intermediate voltage electric power system protection method and device | |
| CN202837471U (en) | Low-current grounding system single-phase earth fault wire discrimination device | |
| CN105846404B (en) | Transmission line of electricity ground distance protection III segment protection methods | |
| CN207098601U (en) | A kind of pro-active intervention formula power distribution network extinguishing arc line selection apparatus |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20170510 |
|
| WD01 | Invention patent application deemed withdrawn after publication |