CN100449899C - High-voltage AC. controllable parallel-connection reactor control winding zero-sequence protection method - Google Patents
High-voltage AC. controllable parallel-connection reactor control winding zero-sequence protection method Download PDFInfo
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- CN100449899C CN100449899C CNB2006101455669A CN200610145566A CN100449899C CN 100449899 C CN100449899 C CN 100449899C CN B2006101455669 A CNB2006101455669 A CN B2006101455669A CN 200610145566 A CN200610145566 A CN 200610145566A CN 100449899 C CN100449899 C CN 100449899C
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Abstract
The method includes steps: protector of reactor obtains instantaneous values of current and voltage by sampling waveforms of threephase current transformer (TA) at secondary side of high voltage, AC controllable type shunt reactor; dedicated external zero sequence current (ZSC) transformer, initial end of threephase potential transformer (TV); using Fourier algorithm determines complex form of each electric quantity; when external ZSC of winding at secondary side is larger than fixed value, the first time limit acts on bypass breaker on joined secondary side through T1 time delayed exit; the second time limit acts on tripping breaker on primary side through T2 time delayed exit; calculating self generated ZSC and self generated zero sequence voltage at initial end, and when ZSC is larger than a fixed value, then warning signal is sent after 5s time delay ; and when locking conditions are not satisfied, the first time limit acts on bypass breaker through T3 time delayed exit etc.
Description
Technical field
The present invention relates to field of power, relate more specifically to the method for relaying protection.
Background technology
At first, according to briefly describing correlation technique of the present invention below with reference to document.
1. Chen Wei is virtuous, Chen He. the controllable adjustment of shunt reactor [J]. and high voltage technique, 2006,26 (5).
2. Li Dayi, Chen Qiaofu, etc. based on the new principle [J] of the controlled Regulatable reactor of magnetic flux. Proceedings of the CSEE, 2003,23 (2).
3. field chromium is emerging, encourages celebrating and inspires confidence in. the magnetic field of transformer type controlled reactor and calculation of parameter [J]. and XI AN JIAOTONG UNIVERSITY Subject Index, 2005,39 (6).
High-voltage shunt reactor is the important part of superhigh pressure, extra-high voltage grid.But installing high-voltage shunt reactor compensated line capacitive power, and can limit switching overvoltage, the Frequency Transient Overvoltage the when appearance when normally moving rises effect and load rejection, the secondary arc current when cooperating neutral grounding reactor effectively to limit single-pole reclosing.But fixedly the capacity of high-voltage shunt reactor can't be regulated, and is difficult to timely and effective control voltage when system load flow changes greatly, has greatly limited the conveying capacity of superhigh pressure and extra high voltage line.After installing fixedly high-voltage shunt reactor additional, be no more than predetermined value for making voltage, long transmission line power delivery ability in addition may be lower than the 50%[1 of natural power].For reduce loss, balance is idle, control voltage, being necessary in the long term to adopt can be according to the high pressure controllable parallel-connection reactor of the automatic pondage of transmission of electricity load.The control of high pressure controllable parallel-connection reactor has the compensation arrangement cost of similar functions lower flexibly relatively, also has the repertoire that fixedly high-voltage shunt reactor possessed concurrently, is the reactive-load compensation equipment of high-voltage fence first-selection.
Under the tissue and support of State Grid Corporation of China, the domestic development work that starts 500kV high pressure controllable parallel-connection reactor.On this basis,, will further develop 1000kV high pressure controllable parallel-connection reactor, fill up domestic and international blank in conjunction with the fixing prior art of high-voltage shunt reactor of 1000kV.
The high pressure controllable parallel-connection reactor and fixedly high-voltage shunt reactor bigger difference is arranged, increased the control winding (hereinafter to be referred as the secondary winding) of a secondary (secondary side) newly, just can control magnetic flux in the magnetic circuit by regulating electric current in the secondary winding, and then can control the capacity of high-voltage shunt reactor.What the present invention is directed to is the high-voltage alternating controllable parallel-connection reactor, and its schematic diagram as shown in Figure 1.Be connected to the little reactor of load at its secondary, change the quantity of the little reactor of load that is inserted, can realize that the classification of capacity is regulated by valve and bypass breaker.Among Fig. 1, when the valve of K100 correspondence only or bypass breaker are closed, corresponding 100% capacity; When the valve of K75 correspondence only or bypass breaker are closed, corresponding 75% capacity; When the valve of K50 correspondence only or bypass breaker are closed, corresponding 50% capacity; When all valves and bypass breaker are all opened, corresponding 25% capacity.The similar transformer of the principle of high-voltage alternating controllable parallel-connection reactor, but with the difference of common transformer be its leakage reactance up to 100%, normally may operate under the operating mode of secondary short circuit in winding, this moment corresponding 100% capacity.Except that the air gap magnetic circuit with common transformer is different, the excitation property of high-voltage alternating controllable parallel-connection reactor iron core is also more linear, flex point is 1.4 times of rated voltages.
Because the high-voltage alternating controllable parallel-connection reactor is different with design feature, the operational mode of common high-voltage shunt reactor, the protection that both disposed is different.The high-voltage alternating controllable parallel-connection reactor can normally move under the situation of secondary short circuit in winding; short circuit current after the secondary fault is as a rule even less than rated current; if protection scheme is improper, the sensitivity of high-voltage alternating controllable parallel-connection reactor protection will be had a greatly reduced quality.The guard method of the former limit of high-voltage alternating controllable parallel-connection reactor fault and fixedly high-voltage shunt reactor protection is similar; but for the turn-to-turn fault and the earth fault of secondary winding, fixedly the longitudinal difference protection of high-voltage shunt reactor configuration, homodyne protection and backup protection all can't be protected.How reliably protecting the fault of the whole secondary of high-voltage alternating controllable parallel-connection reactor system delicately, is the difficult point of high-voltage alternating controllable parallel-connection reactor protection.
Summary of the invention
For remedying the dead band of original fixedly high-voltage shunt reactor protection; the turn-to-turn fault and the earth fault of protection high-voltage alternating controllable parallel-connection reactor secondary; on the basis of analyzing high-voltage alternating controllable parallel-connection reactor principle and design parameter; the present invention proposes the method for high-voltage alternating controllable parallel-connection reactor configuration secondary zero-sequence current protection, comprising external zero sequence overcurrent protection of secondary and the self-produced zero sequence overcurrent protection of residual voltage locking secondary.
Method of the present invention comprises the steps: that the reactor protection device is sampled to the waveform of high-voltage alternating controllable parallel-connection reactor secondary threephase current transformer (hereinafter to be referred as TA), special-purpose external zero sequence TA and head end threephase potential transformer (hereinafter to be referred as TV) and obtains the instantaneous value of current/voltage, wherein the collection of secondary three-phase current selected for use high-precision acquisition circuit; Obtain the plural form of each electric parameters by fourier algorithm; When the external zero-sequence current of secondary winding greater than definite value, first time limit acted on the bypass breaker that closes secondary through T1 time-delay outlet, second time limit acted on the former limit of tripping circuit breaker through T2 time-delay outlet; Calculate the self-produced zero-sequence current of secondary winding simultaneously; When the self-produced zero-sequence current of secondary tripped the section definite value greater than 0.6 times, time-delay 5s sent out alarm signal; When the self-produced zero-sequence current of secondary winding greater than definite value, and following all barring conditions are not when satisfying, first time limit acted on the bypass breaker that closes secondary through T3 time-delay outlet, second time limit acted on the former limit of tripping circuit breaker through T4 time-delay outlet.The condition of the self-produced zero sequence overcurrent protection of locking has: shunt reactor head end zero-pressure is greater than setting value; Unusual or the three-phase of shunt reactor head end TV does not have pressure; Secondary TA is unusual.
According to an aspect of the present invention, the method of the external zero sequence overcurrent protection of a kind of high-voltage alternating controllable parallel-connection reactor configuration secondary is provided, and this method comprises: the reactor protection device is sampled to the waveform of high-voltage alternating controllable parallel-connection reactor secondary threephase current transformer, special-purpose external zero sequence current mutual inductor and head end threephase potential transformer and is obtained the instantaneous value of current/voltage; Obtain the plural form of each electric parameters by fourier algorithm; When the external zero-sequence current of secondary winding greater than definite value, first time limit acted on the bypass breaker that closes secondary through T1 time-delay outlet; If fault signature does not exist, protection is returned; If fault signature still exists, second time limit acted on the former limit of tripping circuit breaker through T2 time-delay outlet.
According to another aspect of the present invention, provide the method for the self-produced zero sequence overcurrent protection of a kind of high-voltage alternating controllable parallel-connection reactor configuration residual voltage locking secondary, this method comprises:
Calculate the self-produced zero-sequence current of secondary winding and the self-produced residual voltage of head end; When the self-produced zero-sequence current of secondary winding greater than definite value, and barring condition is not when satisfying, first time limit acted on the bypass breaker that closes secondary through T3 time-delay outlet; If fault signature does not exist, protection is returned;
If fault signature still exists, second time limit acted on the former limit of tripping circuit breaker through T4 time-delay outlet.
In the present invention, barring condition comprises: shunt reactor head end zero-pressure is greater than setting value; Or shunt reactor head end TV is unusual or three-phase does not have pressure; Perhaps secondary TA is unusual.The self-produced zero sequence overcurrent protection of locking secondary when arbitrary barring condition satisfies in the barring condition.
According to another aspect of the present invention, when the self-produced zero-sequence current of secondary tripped the section definite value greater than 0.6 times, time-delay 5s sent out alarm signal.
Description of drawings
Fig. 1 has shown the installation site of high-voltage alternating controllable parallel-connection reactor principle and current transformer and voltage transformer and the definition of polarity;
Fig. 2 has shown high-voltage alternating controllable parallel-connection reactor secondary zero-sequence current protection logic diagram.
Specific embodiments
The structure of high-voltage alternating controllable parallel-connection reactor as shown in Figure 1; with the structure of common high-voltage shunt reactor a great difference is arranged, if having the dead band of protection when simply the protection of original fixedly high-voltage shunt reactor directly being applied in the high-voltage alternating controllable parallel-connection reactor.On the basis of analyzing high-voltage alternating controllable parallel-connection reactor principle and design parameter; the present invention proposes for the high-voltage alternating controllable parallel-connection reactor disposes the method that the secondary zero-sequence current protection is protected in support, comprising external zero sequence overcurrent protection of secondary and the self-produced zero sequence overcurrent protection of residual voltage locking secondary.
The external zero sequence overcurrent protection of secondary electric current is taken from the special-purpose zero sequence TA0 in reactor secondary earth point place, and the installation site of TA0 is referring to Fig. 1.This protection can be used as the quick protection of whole secondary system earth fault; has natural selectivity; needn't take extra locking measure; can react secondary winding inside, load reactance device inside and secondary terminal earth fault, still have very high sensitivity for the earth fault of distinguishing the interior little turn ratio to the control system cable.And outside the district, reliably be failure to actuate under unbalanced fault and other antisymmetric anomaly operating condition.
The self-produced zero sequence overcurrent protection of residual voltage locking secondary electric current is got the self-produced zero-sequence current that reactor secondary three-phase TA galvanometer is calculated, and voltage is got the self-produced residual voltage that high-voltage shunt reactor head end three-phase TV potentiometer is calculated, and the installation site of TA and TV is referring to Fig. 1.This protection can be used as the backup protection of high-voltage alternating controllable parallel-connection reactor internal fault, lays particular emphasis on the little turn ratio turn-to-turn short circuit of secondary winding, load reactance device and the former limit winding of other protection insufficient sensitivity.
Because jumping high side switch must be careful; outlet mode for the protection of high-voltage alternating controllable parallel-connection reactor has been taked following measure: self-produced zero sequence overcurrent protection of residual voltage locking secondary and the external zero sequence overcurrent protection of secondary divide two time limit outlets; first time limit was closed the by-pass switch of secondary by force; if fault occurs in the secondary cable of high-voltage alternating controllable parallel-connection reactor outside or control appliance etc. and locates; protection will be returned; so just can not lose load, only be that the high-voltage alternating controllable parallel-connection reactor is adjusted operation under 100% capacity.If fault signature still exists after closing the secondary bypass breaker by force, illustrate that then fault occurs in high-voltage shunt reactor inside, above-mentioned two protections will be jumped former limit circuit breaker with second time limit.Promptly for the circuit breaker of bus high-voltage shunt reactor operational mode tripping high-voltage shunt reactor head end; Circuit breaker for circuit high-voltage shunt reactor operational mode tripping circuit both sides.
This method comprises the steps:
The reactor protection device is sampled to the waveform of high-voltage alternating controllable parallel-connection reactor secondary three-phase TA, special-purpose external zero sequence TA and head end three-phase TV and is obtained the instantaneous value of current/voltage.Wherein the collection of secondary three-phase current is selected for use high-precision acquisition circuit, this is to utilize secondary three-phase shortcircuit electric current to equal rated current and the characteristics that needn't consider 20 times of short circuit multiples, and definite value can be adjusted sensitivelyer like this.
Obtain the plural form of each electric parameters by fourier algorithm;
When the external zero-sequence current of secondary winding greater than definite value, first time limit acted on the bypass breaker that closes secondary through T1 time-delay outlet, if this moment, fault signature disappeared, then protection is returned; If fault signature still exists, second time limit acted on the former limit of tripping circuit breaker through T2 time-delay outlet, and wherein T1 and T2 can adjust, and the logic of the external zero sequence overcurrent protection of secondary can be with reference to figure 2A;
The self-produced zero-sequence current of secondary winding is according to formula simultaneously
Calculate, in the formula
Represent secondary A respectively, B, the current phasor of C phase; The self-produced residual voltage of head end is according to formula
Calculate, in the formula
Represent head end A respectively, B, the voltage vector of C phase;
When the self-produced zero-sequence current of secondary tripped the section definite value greater than 0.6 times, the scheduled time of delaying time was sent out alarm signal, and such as 5 seconds (5s), the logic of the self-produced zero sequence overcurrent alarm of secondary can be with reference to figure 2B;
The analysis showed that the residual voltage of high-voltage shunt reactor head end is very little when the high-voltage shunt reactor internal fault, but the residual voltage of high-voltage shunt reactor head end is bigger during the outer unbalanced fault in district.Therefore, has a selectivity, when the self-produced zero sequence overcurrent protection outlet of locking during of former limit zero-pressure greater than setting value for making protection;
Time protection loses selectivity in order to avoid TV unusual, and unusual or three-phase does not have the locking of when pressure and should protection export as TV;
Be the time protection malfunction of avoiding TA unusual, locking should the protection outlet when TA is unusual;
For reducing DC component, the control system of secondary adopts the zero crossing control mode, i.e. the closed A phase of A phase zero crossing valve, and the closed B phase of B phase zero crossing valve, the closed C phase of C phase zero crossing valve, the three-phase that has 13.3ms like this is inconsistent.Therefore the startup of self-produced zero sequence overcurrent protection has added the 20ms time-delay.The self-produced zero-sequence current that is the secondary winding is greater than definite value, and above all barring conditions when not satisfying through the 20ms acknowledging time, the self-produced zero sequence overcurrent protection of residual voltage locking secondary starts.
When the self-produced zero-sequence current of secondary winding greater than definite value, and above all barring conditions are not when satisfying, first time limit acted on the bypass breaker that closes secondary through T3 time-delay outlet, if this moment, fault signature disappeared, then protection is returned; If fault signature still exists, second time limit acted on the former limit of tripping circuit breaker through T4 time-delay outlet, and wherein T3 and T4 can adjust, and the logic of the self-produced zero sequence overcurrent protection of secondary can be with reference to figure 2C.
The experiment and the real system 500kV high-voltage alternating controllable parallel-connection reactor situation of putting into operation show, the self-produced zero sequence overcurrent protection of residual voltage locking secondary to high-voltage alternating controllable parallel-connection reactor internal fault particularly the secondary turn-to-turn fault very high sensitivity is arranged; The external zero sequence overcurrent protection of secondary has very high sensitivity to high-voltage alternating controllable parallel-connection reactor secondary earth fault; These two all reliably not malfunctions of zero-sequence current protection in the transient state steady-state process of external area error, open-phase operation and normal running.
Claims (9)
1, the method for the external zero sequence overcurrent protection of a kind of high-voltage alternating controllable parallel-connection reactor configuration secondary, this method comprises:
The reactor protection device is sampled to the waveform of high-voltage alternating controllable parallel-connection reactor secondary threephase current transformer, special-purpose external zero sequence current mutual inductor and head end threephase potential transformer and is obtained the instantaneous value of current/voltage;
Obtain the plural form of each electric parameters by fourier algorithm;
When the external zero-sequence current of secondary winding greater than definite value, first time limit acted on the bypass breaker that closes secondary through T1 time-delay outlet;
If fault signature disappears after closing the bypass breaker of secondary, protection is returned;
If fault signature still exists, second time limit acted on the former limit of tripping circuit breaker through T2 time-delay outlet.
2, method as claimed in claim 1, wherein said T1 and T2 predetermined value for being provided with.
3, the method for the self-produced zero sequence overcurrent protection of a kind of high-voltage alternating controllable parallel-connection reactor configuration residual voltage locking secondary, this method comprises:
Calculate the self-produced zero-sequence current of secondary winding and the self-produced residual voltage of head end;
When the self-produced zero-sequence current of secondary winding greater than definite value, and barring condition is not when satisfying, first time limit acted on the bypass breaker that closes secondary through T3 time-delay outlet;
If fault signature disappears after closing the bypass breaker of secondary, protection is returned;
If fault signature still exists, second time limit acted on the former limit of tripping circuit breaker through T4 time-delay outlet.
4, method as claimed in claim 3, wherein barring condition comprises: shunt reactor head end residual voltage is greater than setting value.
5, method as claimed in claim 3, wherein barring condition comprises: the unusual or three-phase of shunt reactor head end TV does not have pressure.
6, method as claimed in claim 3, wherein barring condition comprises: secondary TA is unusual.
7, method as claimed in claim 3, the self-produced zero sequence overcurrent protection of locking secondary when arbitrary barring condition satisfies in the wherein said barring condition.
8, method as claimed in claim 3, wherein when the self-produced zero-sequence current of secondary tripped the section definite value greater than 0.6 times, the scheduled time of delaying time was sent out alarm signal.
9, method as claimed in claim 3, wherein said T3 and T4 predetermined value for being provided with.
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| CN101630832B (en) * | 2008-07-15 | 2012-07-04 | 许继集团有限公司 | Method for judging single-phase earth fault of controllable high-voltage shunt reactor |
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| CN105529687B (en) * | 2016-01-28 | 2017-12-22 | 南京南瑞继保电气有限公司 | A kind of quick zero-sequencedirectional protection method of transformer |
| CN107919651B (en) * | 2017-12-15 | 2019-08-23 | 国家电网公司华中分部 | A kind of pumping energy reactor pumping energy winding inter-turn zero-sequenceprotection method and device |
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| CN110556783B (en) * | 2019-09-10 | 2021-10-22 | 许昌许继软件技术有限公司 | Zero sequence overcurrent protection method and device for transformer |
| CN112350275B (en) * | 2020-09-30 | 2023-03-24 | 国网宁夏电力有限公司检修公司 | Current transformer disconnection identification method, protection method, medium and system |
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| CN1119796A (en) * | 1994-05-19 | 1996-04-03 | 株式会社日立制作所 | Apparatus and method for inhibiting earth current |
| CN1555115A (en) * | 2003-12-24 | 2004-12-15 | 北京四方继保自动化有限公司 | Digital high votage parallel reactor longitudinal protection with end braking |
| CN1555116A (en) * | 2003-12-24 | 2004-12-15 | 北京四方继保自动化有限公司 | Fault-tolerant complex judging self adaption high voltage parallel reactor turn-to-turn protection |
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Patent Citations (3)
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| CN1119796A (en) * | 1994-05-19 | 1996-04-03 | 株式会社日立制作所 | Apparatus and method for inhibiting earth current |
| CN1555115A (en) * | 2003-12-24 | 2004-12-15 | 北京四方继保自动化有限公司 | Digital high votage parallel reactor longitudinal protection with end braking |
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Effective date of registration: 20180102 Address after: 100085 Beijing city on the base of the information industry on the street, No. four, No. 9, Haidian District Co-patentee after: Beijing Sifang Jibao Engineering Technology Co., Ltd. Patentee after: Beijing Sifang Jibao Automation Co., Ltd. Address before: 100085 Beijing city on the base of the information industry on the street, No. four, No. 9, Haidian District Patentee before: Beijing Sifang Jibao Automation Co., Ltd. |