CN1790039A - Method for judging generator PT line failure - Google Patents
Method for judging generator PT line failure Download PDFInfo
- Publication number
- CN1790039A CN1790039A CN 200510123095 CN200510123095A CN1790039A CN 1790039 A CN1790039 A CN 1790039A CN 200510123095 CN200510123095 CN 200510123095 CN 200510123095 A CN200510123095 A CN 200510123095A CN 1790039 A CN1790039 A CN 1790039A
- Authority
- CN
- China
- Prior art keywords
- groups
- generator
- phase
- negative sequence
- sequence component
- 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
Landscapes
- Tests Of Circuit Breakers, Generators, And Electric Motors (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The invention discloses a pressure transformer (PT) breakage judgment method, which is characterized by the following: the judgment method contains the first and second judgments to judge the breakage fault combination of two groups of motor PT especially in the condition that the PT measuring value is small and the rotor current is bigger and the stator current is normal; when three phases of two groups of PT are broken simultaneously, the voltage is zero without negative sequence component and the first and second judgments are both in the failure state; when the rotor current is bigger and more than the preset value of corresponding motor, two groups of PT measuring value is low and less than the preset value of corresponding motor; three phases short-circuit of motor outlet happens or two groups of PT breaks; the difference of two conditions is that when the measuring value of stator current varies, the circuit becomes short and the measuring value of rotor current increases.
Description
Technical field
The present invention relates to a kind of generator voltage measuring transformer (PT) determination methods, promptly generator voltage measuring transformer PT broken string determination methods can be judged the disconnection fault combination that two groups of PT of generator are all, and can distinguish PT broken string and generator outlet short circuit.
Background technology
The correct judgement of generator machine end PT broken string, concerning machine end PT as extremely important the excitation system of control benchmark.At present, the conventional method of judging generator machine end PT broken string is mainly two PT relative methods, usually generator machine end all is provided with two groups of PT, control device is accepted two groups of PT voltages simultaneously, under the normal condition, the measured value of two groups of PT equates, compares two groups of PT voltage measuring values, when one group of PT measured value descends suddenly, judge that then disconnection fault takes place this PT.This method is very effective to single group PT broken string, but when two groups of PT break simultaneously, just can not correctly judge the PT broken string; In addition, can not judge the difference of two groups of PT broken strings and generator outlet short circuit.
Summary of the invention
The present invention seeks to: in order to solve the deficiency that conventional PT broken string determination methods is distinguished with short circuit at judgement that two groups of PT break simultaneously and broken string, the present invention proposes a kind of new PT broken string determination methods, two groups of PT carry out complete detection to generator machine end, and combine with generator unit stator electric current and rotor current, correct all combinations of judging two groups of PT broken strings of generator: single group PT broken string, two groups of single-phase (A of PT, B, C) or two-phase breaks simultaneously, two groups of three-phases break simultaneously.The disconnection fault combination that two groups of PT of generator are all can be judged, and PT broken string and generator outlet short circuit can be distinguished.
Technical solution of the present invention is: three kinds of criterions are set in the methods of the invention, and any criterion satisfies can be judged as the PT broken string, and can not be judged as the PT broken string to the generator short circuit situation by mistake.
Method for judging generator PT line failure: first kind of criterion is that two groups of PT measured values compare, consistent with conventional method, when having only one group of PT that broken string takes place, this group PT measured value can descend suddenly, and another group PT measurement simultaneously remains unchanged, when generator outlet is short-circuited, two groups of PT can reduce simultaneously, therefore, this method is very effective to single group PT broken string, and the generator outlet short circuit can not be judged as the PT broken string by mistake.
Second kind of criterion is: occur negative sequence component and (generator zero load or stator current do not have negative sequence component in measuring) during PT measures, this criterion is primarily aimed at two groups of single-phase or two-phase while disconnection faults of PT, for three-phase symmetric voltage or electric current, under the normal condition, negative sequence component can not appear, but when three-phase asymmetric (one mutually or two-phase increase or reduce), negative sequence component can appear in measured value, as two groups of PT during single-phase simultaneously or two-phase broken string, negative sequence component can appear in the voltage measurement, because generator unit stator normally moves, therefore its stator current negative sequence component can not occur in measuring, but when single-phase or line to line fault occurring, stator current negative sequence component will occur in measuring, therefore, this criterion can distinguish short-circuit and the PT broken string, when the generator outlet short circuit, excitation controlling device can correctly be controlled, and can not be judged as the PT broken string by mistake.
The third criterion is: this criterion is primarily aimed at two groups of PT three-phases and breaks simultaneously, and it all is zero that two groups of PT three-phase voltages are measured, and does not also have negative sequence component, and first kind and second kind of criterion all lost efficacy.Under the normal condition, generator unit stator voltage and rotor current are associated, if when rotor current is big, two groups of PT measured values are very low, have only two kinds of possibilities, generator outlet generation three-phase shortcircuit, otherwise all broken strings take place in two groups of PT, and the difference of two kinds of situations is the variation of stator current measured value, when being short-circuited, the stator current measured value can increase, and like this, just can correctly judge two groups of heterogeneous broken strings of PT homophase.
When the PT measured value is very little and rotor current is big and stator current is normal, when two groups of PT three-phases break simultaneously, two groups of PT three-phase voltage measurements all are zero or are close to zero, there is not negative sequence component yet, first kind and second kind of equal invalid state of criterion: then when rotor current is big and greater than certain definite value, set definite value accordingly with generator, two groups of PT measured values are very low (less than certain definite value, set definite value accordingly with generator), various capacity differences, the set end voltage difference, power factor 0.8, the generator that rated exciting current 1000A is different, each definite value is also inequality, the setting of definite value is fully according in the prior art comprehensive parameters of generator being set, and is not special setting of the present invention); Then occur as judging: generator outlet generation three-phase shortcircuit, or two groups of whole broken strings of PT generation, the difference of two kinds of situations is the variation of stator current measured value, when being short-circuited, the stator current measured value can increase; Thereby correctly judge two groups of heterogeneous broken strings of PT homophase.
The invention has the beneficial effects as follows: new PT broken string determination methods, by complete detection generator voltage, stator current and rotor current, according under various PT broken strings and short-circuit conditions, the different variation combinations of generator voltage, stator current and rotor current, the various PT disconnection faults of correct judgement, and can correctly distinguish PT broken string and generator outlet short circuit, for the generator excitation control device provides correct control benchmark, guarantee the normal safe operation of generator.Comprehensive and the perfect method that the present invention judges for generator PT line failure in fact.
Description of drawings
Fig. 1 is a logic theory block diagram of the present invention
Embodiment
PT1 is the 1st a group of PT measured value among Fig. 1, and PT2 is the 2nd a group of PT measured value, and IF is the rotor current measured value, and IG is the stator current measured value, a, b, c, d, e, f, g is a setting parameter, adjusts according to generator parameter, for example at certain generator (set end voltage 10.5KV, capacity 125MVA, power factor 0.8, rated exciting current 1000A), a then, b, c, d, e, f, the g definite value is respectively: 1KV, 8KV, 2KV, 1KA, 0.5KV, 300A, 10KA.Setting valve choose with reference to existing P T breaking protection the time parameter.
Logic diagram has illustrated the logic determines process of the inventive method among Fig. 1.
Claims (1)
1, method for judging generator PT line failure: it is characterized in that determination methods comprises three kinds of criterions:
First kind of criterion is: two groups of PT measured values compare, and when having only one group of PT that broken string takes place, this group PT measured value descends suddenly, and another group PT measurement simultaneously remains unchanged, and when generator outlet was short-circuited, two groups of PT reduced simultaneously;
Second kind of criterion is: occur not having negative sequence component in the measurement of negative sequence component and generator zero load or stator current during PT measures, this is at two groups of single-phase or two-phase while disconnection faults of PT, as two groups of PT during single-phase simultaneously or two-phase broken string, negative sequence component appears in the voltage measurement, when generator unit stator normally moved, stator current negative sequence component do not occur in measuring; When single-phase or line to line fault occurring, stator current negative sequence component just occurs in measuring; This criterion can distinguish short-circuit and the PT broken string; When the generator outlet short circuit, excitation controlling device can correctly be controlled, and does not judge the broken string into PT by accident;
The third criterion is: when the PT measured value is very little and rotor current is big and stator current is normal, when two groups of PT three-phases break simultaneously, it all is zero that two groups of PT three-phase voltages are measured, there is not negative sequence component yet, first kind and second kind of equal invalid state of criterion: then when rotor current is big and when setting definite value accordingly with generator, two groups of PT measured values are very low and less than setting definite value accordingly with generator; Then occur as judging: generator outlet generation three-phase shortcircuit, or all broken strings take place in two groups of PT; The difference of two kinds of situations is the variation of stator current measured value, and when being short-circuited, the stator current measured value increases; Thereby judge two groups of heterogeneous broken strings of PT homophase.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005101230957A CN100363750C (en) | 2005-12-15 | 2005-12-15 | Method for judging generator PT line failure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005101230957A CN100363750C (en) | 2005-12-15 | 2005-12-15 | Method for judging generator PT line failure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1790039A true CN1790039A (en) | 2006-06-21 |
| CN100363750C CN100363750C (en) | 2008-01-23 |
Family
ID=36788031
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005101230957A Active CN100363750C (en) | 2005-12-15 | 2005-12-15 | Method for judging generator PT line failure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100363750C (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102890222A (en) * | 2012-10-17 | 2013-01-23 | 南京国电南自美卓控制系统有限公司 | Method for judging breaking of PT (potential transformer) in fast switch |
| CN103091595A (en) * | 2012-07-23 | 2013-05-08 | 南京南瑞继保电气有限公司 | Discriminated method of generator terminal voltage mutual inductor once-off-line |
| CN104035001A (en) * | 2014-06-25 | 2014-09-10 | 国家电网公司 | Detection method for disconnection of voltage transformers |
| CN104297625A (en) * | 2014-11-07 | 2015-01-21 | 安徽马钢自动化信息技术有限公司 | PT wire breakage diagnosis system and method |
| CN109541469A (en) * | 2019-01-09 | 2019-03-29 | 中国长江电力股份有限公司 | A kind of generator excited system PT broken string method of discrimination |
| CN110703096A (en) * | 2019-10-29 | 2020-01-17 | 江苏瑞奇海力科技有限公司 | Motor working state detection method, device, equipment and storage medium |
| CN110880890A (en) * | 2019-11-05 | 2020-03-13 | 武汉武水电气技术有限责任公司 | Low pressure hydraulic generator protection system |
| CN112557957A (en) * | 2019-09-09 | 2021-03-26 | 南京南瑞继保工程技术有限公司 | Method, device and system for judging PT (potential transformer) disconnection of magnetic control type controllable shunt reactor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07170798A (en) * | 1993-12-16 | 1995-07-04 | Hitachi Ltd | Abnormality diagnositic method for exciting equipment for synchronous machine |
-
2005
- 2005-12-15 CN CNB2005101230957A patent/CN100363750C/en active Active
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103091595A (en) * | 2012-07-23 | 2013-05-08 | 南京南瑞继保电气有限公司 | Discriminated method of generator terminal voltage mutual inductor once-off-line |
| CN103091595B (en) * | 2012-07-23 | 2015-09-02 | 南京南瑞继保电气有限公司 | The method of discrimination that a kind of generator terminal voltage mutual inductor once breaks |
| CN102890222A (en) * | 2012-10-17 | 2013-01-23 | 南京国电南自美卓控制系统有限公司 | Method for judging breaking of PT (potential transformer) in fast switch |
| CN104035001A (en) * | 2014-06-25 | 2014-09-10 | 国家电网公司 | Detection method for disconnection of voltage transformers |
| CN104035001B (en) * | 2014-06-25 | 2016-03-16 | 国家电网公司 | A kind of detection method of voltage transformer disconnection |
| CN104297625A (en) * | 2014-11-07 | 2015-01-21 | 安徽马钢自动化信息技术有限公司 | PT wire breakage diagnosis system and method |
| CN109541469A (en) * | 2019-01-09 | 2019-03-29 | 中国长江电力股份有限公司 | A kind of generator excited system PT broken string method of discrimination |
| CN109541469B (en) * | 2019-01-09 | 2021-09-17 | 中国长江电力股份有限公司 | PT disconnection judging method for generator excitation system |
| CN112557957A (en) * | 2019-09-09 | 2021-03-26 | 南京南瑞继保工程技术有限公司 | Method, device and system for judging PT (potential transformer) disconnection of magnetic control type controllable shunt reactor |
| CN110703096A (en) * | 2019-10-29 | 2020-01-17 | 江苏瑞奇海力科技有限公司 | Motor working state detection method, device, equipment and storage medium |
| CN110880890A (en) * | 2019-11-05 | 2020-03-13 | 武汉武水电气技术有限责任公司 | Low pressure hydraulic generator protection system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100363750C (en) | 2008-01-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100363750C (en) | Method for judging generator PT line failure | |
| KR101066700B1 (en) | Power converter | |
| KR101182881B1 (en) | Driving controller of ac motor | |
| CN113454866B (en) | Method and apparatus for controlling power to a protected electrical load | |
| US20130222951A1 (en) | Fault protection circuit for photovoltaic power system | |
| CN107121630A (en) | The self checking method and device of a kind of active short-circuit protection circuit of electric machine control system | |
| CN104599901B (en) | Detection circuit for contactor | |
| CN101651329A (en) | Judgment method of line breakage of special TV for inter-turn protection of generator | |
| CN104882863B (en) | A kind of power plant auxiliary system relay protection scheme complexes | |
| WO2022016595A1 (en) | Method for inspecting electrical wear state of circuit breaker contact using arc power | |
| CN109743003A (en) | A kind of permanent magnet synchronous motor end short-circuit protection method based on PI controller | |
| CN111044901A (en) | Fault early warning method and system for double-mode shield machine | |
| CN110320432B (en) | Single-phase line-breaking fault detection and protection method and system | |
| US12017542B2 (en) | Safety circuit for a power system of a vehicle and method for controlling the safety circuit | |
| CN101807789A (en) | Out-of-step protection method for synchronous motor | |
| CN107769163A (en) | A kind of guard method, system and the device of tractive transformer oil pump | |
| CN117491868A (en) | Method and device for detecting non-full-phase operation of generator end breaker GCB | |
| CN116683402A (en) | Method and structure for rapidly cutting excitation transformation fault of self-shunt excitation generator | |
| CN101714779B (en) | Directional current based shutting method of high-speed switching device of industrial enterprise power supply | |
| CN105606926B (en) | A kind of method of failure between positioning DC deicing device change of current change and transverter | |
| Jahić et al. | Detection of failures on the high-voltage cage induction motor rotor | |
| Aree | Effects of neutral conductor on induction motor steady-state performance under loss of one phase of supply voltages | |
| US8125747B2 (en) | Method for mitigating negative sequence effect resulting from non-symmetrical short circuit failure of synchronous electric machine based systems | |
| CN110556784B (en) | Relay protection configuration and setting method for high-voltage distribution system of ferroalloy electric furnace | |
| CN113964806A (en) | Electrical fireproof current-limiting short circuit protection method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| ASS | Succession or assignment of patent right |
Owner name: NANJING NANRUIJUBAO ENGINEERING TECHNOLOGY CO., L Free format text: FORMER OWNER: NANRUI JIBAO ELECTRIC CO., LTD. Effective date: 20080627 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20080627 Address after: Zip Road, Jiangning District, Jiangsu, Nanjing: 211100 Co-patentee after: Nanrui Relay Protection Electricity Co., Ltd., Nanjing Patentee after: Nanjing Nan relic Engineering Technology Co., Ltd. Address before: Zip Road, Jiangning District, Jiangsu, Nanjing: 211100 Patentee before: Nanrui Relay Protection Electricity Co., Ltd., Nanjing |