CN102244379B - Method, device and system for controlling and protecting serial capacitors - Google Patents
Method, device and system for controlling and protecting serial capacitors Download PDFInfo
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- CN102244379B CN102244379B CN201110192299.1A CN201110192299A CN102244379B CN 102244379 B CN102244379 B CN 102244379B CN 201110192299 A CN201110192299 A CN 201110192299A CN 102244379 B CN102244379 B CN 102244379B
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- 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
- H02H7/16—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 capacitors
Abstract
The invention discloses a method, device and system for controlling and protecting serial capacitors. The serial capacitors comprise a plurality of shared node branches, wherein each branch among the plurality of shared node branches is provided with one current transformer which is used for measuring current signals on the branch; and the plurality of shared node branches comprise bypass breaker branches. The method comprises the following steps: receiving current signals which are measured by each current transformer in the plurality of shared node branches at the same sampling time; identifying whether the current signals in the plurality of shared node branches meet the KCL (Kirchhoff's current law); and determining the current signals in the plurality of shared node branches to be incredible when the current signals in the plurality of shared node branches do not meet the KCL, thus locking the current protection of the serial capacitors. The current signals in the plurality of shared node branches in the serial capacitors are judged to be incredible exactly, thus improving the reliability and safety of protection of the serial capacitors.
Description
Technical field
The present invention relates to AC transmission system, particularly relate to control guard method, the equipment and system of series capacitance apparatus.
Background technology
The series capacitor compensation technology of AC transmission system (be called for short: string is mended) is that power capacitor is series in transmission line of alternation current, for compensating the part emotional resistance of transmission line of alternation current, thereby reach purposes such as increasing circuit transmission capacity, the raising stability of a system, saving investment.In remote, large capacity transmission system, increase along with transmission distance, its conveying capacity is subject to increasing restriction, and the string revisal is to address this problem, improve one of important means of ultra-high/extra-high voltage transmission line ability of supplying electric power, therefore has very huge economic worth.String benefit technology obtains a wide range of applications in the electric power system of countries in the world at present.
Thyristor controlled series capacitor compensation arrangement (THYRISTOR CONTROLLED SERIES CAPACITORS, be called for short: the equivalent impedance of fundamental frequency of TCSC) by the Trigger Angle that changes thyristor, regulating TCSC, the dynamic control of realization to equivalent impedance of fundamental frequency, thereby can further improve stability of power system, increase the transmission capacity of transmission line, suppress low-frequency oscillation of electric power system and subsynchronous resonance.When the ultra-high/extra-high voltage transmission line is short-circuited fault, TCSC proceeds to thyristor bypass series capacitor pattern immediately, can reduce the short circuit current of system, improves the stability of electric power system.
Along with developing rapidly of electric power system, the load in unit and station capacity, substation capacity, city and the center of industry and the continuation of load density increase, and interconnected between electric power system, cause the short circuit current level in modern large power system electrical networks at different levels constantly to increase.Short circuit current exceeds standard becomes one of major issue that threatens the modern power systems safe operation.Except changing electric network composition, (FAULT CURRENT LIMITER is called for short: be FCL) to solve short circuit current exceed standard new approaches and the new way of problem the series resonant-type fault current limiter device.2009, the superhigh pressure fault current limiter device was at East China Power Grid 500kV bottle kiln electric substation hanging net operation, and this device is in the stage of applying.
Such as the fixed series capacitors compensation arrangement, (FIXED SERIES COMPENSATION is called for short: FSC), the series capacitance apparatus of TCSC, FCL etc. has similar control protection system.The Main Function of controlling protection system is: measure in service various to installing disadvantageous failure condition, the relevant protection of correct operation, isolated fault timely and accurately, the safe and stable operation of assurance device, and coordinate route protection to carry out the miscellaneous equipment in protection system.In addition; the functions such as the control protection system also has electrical quantities measurement and gathers, monitoring running state, record ripple, man-machine interaction; in station, realize bypass breaker (BYPASS CIRCUIT BREAKER; be called for short: BCB), isolation switch (DISCONNECTOR), grounding switch (GROUND DISCONNECTOR; be called for short: supervision and the control of all key equipment states such as GD) realizes the supervision to key equipment state by telecontrol equipment in dispatching office.
(METAL OXIDE VARISTOR, be called for short: MOV) overcurrent protection, MOV protecting energy, MOV temperature protection, MOV unbalance protection, spark gap (GAP) are refused trigger protection, the protection of GAP delayed trigger, capacitor unbalance protection, capacitor super-load protection etc. from trigger protection, GAP to relate generally to metal oxide pressure-limiting device such as the control protection system of the series capacitance apparatus of FSC, TCSC and FCL.More than realizing, required current signal has the electric current of line current, capacitor branch current, capacitor unbalance electric current, MOV electric current and GAP usually during various defencive function.Can cause associated current protection malfunction or tripping because each incredible current signal is sent to the control protection system, therefore have influence on reliability and the fail safe that string is mended unit protection, bring unnecessary economic loss.Cause the incredible factor of current signal to have a lot, for example, (ANALOG-TO-DIGITAL is called for short: A/D) operation exception of translation exception, data summarization unit etc. for the misoperation of outside electromagnetic interference, programmable logic device, modulus.
Summary of the invention
The present invention requires the technical problem solved to be: provide a kind of control guard method, equipment and system of series capacitance apparatus, to improve the reliability and security of series capacitor unit protection.
A kind of control guard method of series capacitance apparatus is provided in one aspect of the invention.Wherein said series capacitance apparatus comprises a plurality of total node branch roads, be respectively arranged with a current transformer on each total node branch road in described a plurality of total node branch road, for the current signal on the total node branch road in its place, measured, described a plurality of total node branch road comprises the bypass breaker branch road, and the method comprises:
Receive each current transformer current signal in the described a plurality of total node branch road of same sampling instant measurement respectively;
Whether the current signal of identifying in the described a plurality of total node branch roads of same sampling instant meets Kirchhoff's current law (KCL);
If the current signal in the described a plurality of total node branch roads of same sampling instant does not meet Kirchhoff's current law (KCL), determine that the current signal in described a plurality of total node branch road is insincere;
When the current signal in described a plurality of total node branch roads is insincere, the current protection of the described series capacitance apparatus of locking.
A kind of control protective unit of series capacitance apparatus is provided in one aspect of the invention.Wherein said series capacitance apparatus comprises a plurality of total node branch roads; be respectively arranged with a current transformer on each total node branch road in described a plurality of total node branch road; for the current signal on the total node branch road in its place, measured; described a plurality of total node branch road comprises the bypass breaker branch road, and this control protective unit comprises:
Receiving element, for receiving the current signal of described a plurality of total node branch roads that each current transformer measures in same sampling instant respectively;
Whether recognition unit, meet Kirchhoff's current law (KCL) for the current signal of identifying the described a plurality of total node branch roads of same sampling instant;
Determining unit, for the recognition result according to described recognition unit, if the current signal in the described a plurality of total node branch roads of same sampling instant does not meet Kirchhoff's current law (KCL), determine that the current signal in described a plurality of total node branch road is insincere;
Performance element, when insincere for the current signal of determining described a plurality of total node branch roads in described determining unit, the current protection of the described series capacitance apparatus of locking.
A kind of control protection system of series capacitance apparatus is provided in one aspect of the invention.Wherein said series capacitance apparatus comprises a plurality of total node branch roads, be respectively arranged with a current transformer on each total node branch road in described a plurality of total node branch road, for the current signal on the total node branch road in its place, measured, described a plurality of total node branch road comprises the bypass breaker branch road, and this control protection system comprises platform data acquisition system and the first protective device;
Described platform data acquisition system, carry out filtering, analog-to-digital conversion for the current signal of the described a plurality of total node branch roads to measuring in same sampling instant respectively from each current transformer, and the current signal after processing sent to the first protective device;
Described the first protective device, the current signal sent for the receiving platform data acquisition system; Whether the current signal of identifying in the described a plurality of total node branch roads of same sampling instant meets Kirchhoff's current law (KCL); If the current signal in the described a plurality of total node branch roads of same sampling instant does not meet Kirchhoff's current law (KCL), determine that the current signal in described a plurality of total node branch road is insincere; When the current signal in described a plurality of total node branch roads is insincere, the current protection of the described series capacitance apparatus of locking.
The present invention is by arranging respectively a current transformer (CURRENT TRANSFORMER on a plurality of total node branch road that comprises the BCB branch road at the series capacitance apparatus; be called for short: TA); thereby can measure the current signal on a plurality of total node branch roads in the series capacitance apparatus; and can utilize Kirchhoff's current law (KCL) accurately to judge that in the series capacitance apparatus, whether the current signal on a plurality of total node branch roads is credible, thereby improve the reliability and security of series capacitor unit protection.
The accompanying drawing explanation
The flow chart of the embodiment of control guard method that Fig. 1 is series capacitance apparatus of the present invention;
The structural representation that Fig. 2 is an embodiment of series capacitance apparatus in the present invention;
The structural representation that Fig. 3 is another embodiment of series capacitance apparatus in the present invention;
The structural representation that Fig. 4 is another embodiment of series capacitance apparatus in the present invention;
The flow chart of another embodiment of control guard method that Fig. 5 is series capacitance apparatus of the present invention;
The flow chart of another embodiment of control guard method that Fig. 6 is series capacitance apparatus of the present invention;
The structural representation of the embodiment of control protective unit that Fig. 7 is series capacitance apparatus of the present invention;
The structural representation of another embodiment of control protective unit that Fig. 8 is series capacitance apparatus of the present invention;
The structural representation of the embodiment of control protection system that Fig. 9 is series capacitance apparatus of the present invention;
The structural representation of another embodiment of control protection system that Figure 10 is series capacitance apparatus of the present invention;
The structural representation of another embodiment of control protection system that Figure 11 is series capacitance apparatus of the present invention;
Figure 12 be according to the present invention in the structural representation of another embodiment of series capacitance apparatus.
Specific embodiment
With reference to the accompanying drawings the present invention is described more fully, exemplary embodiment of the present invention wherein is described.
The flow chart of the embodiment of control guard method that Fig. 1 is series capacitance apparatus of the present invention.Wherein in this embodiment, the series capacitance apparatus comprises a plurality of total node branch roads, be respectively arranged with a current transformer on each total node branch road in a plurality of total node branch roads, for the current signal on the total node branch road in its place, measured, the plurality of total node branch road comprises the bypass breaker branch road.As shown in Figure 1, the control guard method of this embodiment series capacitance apparatus is as follows:
The control guard method of the series capacitance apparatus provided based on the above embodiment of the present invention; owing on a plurality of total node branch road that comprises the BCB branch road at the series capacitance apparatus, a TA being set respectively; thereby can measure the current signal on a plurality of total node branch roads in the series capacitance apparatus; and can utilize Kirchhoff's current law (KCL) accurately to judge that in the series capacitance apparatus, whether the current signal on a plurality of total node branch roads is credible, thereby improve the reliability and security of series capacitor unit protection.
According to a specific embodiment of the present invention, the series capacitance apparatus can be FSC, TCSC, FCL, or other similar device.Fig. 2 is the structural representation of an embodiment of series capacitance apparatus in the present invention, and in Fig. 2, the series capacitance apparatus is FSC, specifically comprises series circuit branch road, capacitor group branch road, MOV branch road, GAP branch road and BCB branch road.Fig. 3 is the structural representation of another embodiment of series capacitance apparatus in the present invention, in Fig. 3, the series capacitance apparatus is TCSC, specifically comprise series circuit branch road, capacitor group branch road, thyristor bypass branch, MOV branch road, GAP branch road and BCB branch road, wherein as required the GAP branch road can be arranged, also can there is no the GAP branch road.Fig. 4 is the structural representation of another embodiment of series capacitance apparatus in the present invention, in Fig. 4, the series capacitance apparatus is FCL, specifically comprise series circuit branch road, capacitor group branch road, MOV branch road, GAP branch road, thyristor bypass branch and BCB branch road, at least one in GAP and thyristor bypass branch wherein can be set as required.In Fig. 2-embodiment illustrated in fig. 4, on each series capacitance apparatus comprises the whole total node branch road of BCB branch road, a TA is set respectively.Like this, all can measure current signal on all branch roads such as the series circuit branch road in each series capacitance apparatus, capacitor group branch road, MOV branch road, GAP branch road, BCB branch road.Capacitor group shown in Fig. 2, Fig. 3 and Fig. 4 can require to adopt the wiring of H type, double H-type wiring etc. according to capacity, anti-quick-fried, overvoltage multiple etc., the current signal that the related branch current signal of criterion used due to the present invention is each total node branch road, therefore do not embody the mode of connection of capacitor group and the configuration mode of uneven TA in the drawings.
According to another specific embodiment of the present invention, the step 102 of embodiment based on shown in Fig. 1, if the current signal in a plurality of total node branch roads of same sampling instant meets Kirchhoff's current law (KCL), can determine that the current signal in a plurality of total node branch roads is credible.Now can utilize current signal on each branch road of series capacitance apparatus to carry out the current protection of series capacitance apparatus.
The flow chart of another embodiment of control guard method that Fig. 5 is series capacitance apparatus of the present invention.As shown in Figure 5, the control guard method of this embodiment series capacitance apparatus is as follows:
In this embodiment; in the incredible situation of current signal; cause erroneous judgement for avoiding indivedual sampling instants accidentally not meet Kirchhoff's current law (KCL), adopt the delay lock way that sends again the latch-up protection signal after M continuous sampling instant of judgement all do not meet Kirchhoff's current law (KCL).By the mode of this continuous judgement, can effectively avoid current signal accidentally not meet logic criterion and the erroneous judgement that causes in indivedual sampling instants, thereby guarantee the reliability of judgement.
Below make a concrete analysis of the relation between current signal in each total node branch road of series capacitance apparatus.The tie point that each branch road of series capacitance apparatus and series circuit branch road are common, be called with reference to node, and the branch road associated with the reference node is called total node branch road.For example in the present invention shown in Fig. 2 in the structural representation of an embodiment of series capacitance apparatus, the common tie point A of each branch road of FSC and series circuit branch road 1 is with reference to node, and the branch road associated with reference node A is called total node branch road.For example, in Fig. 2, series circuit branch road that will be associated with reference node A, capacitor group branch road, MOV branch road, GAP branch road and BCB branch road are called total node branch road.Known according to Kirchhoff's current law (KCL), flow into this electric current with reference to node and equal to flow out this electric current with reference to node.Getting each branch road, to flow into this direction with reference to node be positive direction, comprises that the series circuit branch road has n branch road,
or
wherein, i
ibe the instantaneous value of branch current signal on i branch road, i
ibe the phasor value of branch current on i branch road, subscript i means i branch road.
The current signal i of each branch road that current transformer obtains in sampling instant
t.i, wherein subscript T means sampling instant, subscript i means i branch road.The real primary current signal of each branch road becomes the secondary current signal, pass through again electromagnetic interference (ELECTROMAGNETIC INTERFERENCE, be called for short: EMI) filter, signal condition unit, the instantaneous sampling data that the steps such as A/D converting unit, opto-electronic conversion obtain, compare and have certain error with actual value Direct Sampling data, therefore, get
δ>0 be approximately zero wherein, n is number of branches.δ is under the believable prerequisite of current signal, the series capacitance apparatus under different operating conditions the maximum absolute error value of getable sample rate current signal algebraical sum absolute value, can and obtain with reference to empirical value by a large amount of test recorder datas or on-the-spot service data.
Suppose that the 1st branch road is the series circuit branch road, n branch road is the BCB branch road, and the positive direction of all total node current branch roads is for flowing to the direction with reference to node.
1) when the series capacitance apparatus normally moves, bypass breaker is opened,
2) certain fault occurs and BCB has received the order of closing a floodgate when circuit generating region internal fault or series capacitance apparatus, closed BCB (closing moment t=0), according to Kirchhoff's current law (KCL),
3) at t=t
1series capacitance apparatus capacitor group, each branch currents such as MOV, GAP decay to zero constantly, and while reaching stable state, BCB branch current signal equals series circuit branch current signal,
Under above three kinds of operating modes, each total node branch road of series capacitance apparatus is less than or equal to definite value δ at the absolute value of the sampled value algebraical sum of the current signal of each sampling instant, and the absolute value of the absolute value difference of the sampled value of the absolute value of the sampled value algebraical sum of the current signal constantly at each of all the other the total node branch roads except the BCB branch road and BCB place branch current signal also is less than or equal to definite value δ.Therefore, in a specific embodiment of the present invention, the logic criterion that whether meets Kirchhoff's current law (KCL) for identifying current signal is:
Suan Fu & wherein; For the logic and operation symbol.Above-mentioned criterion comprises two parts, and the first criterion is
second Criterion is
when the logical value of this logic criterion is 1, mean that the first criterion and Second Criterion all set up, now mean that the current signal on a plurality of total node branch roads meets Kirchhoff's current law (KCL).And the logical value of working as this logic criterion is 0, mean in the first criterion and Second Criterion the invalid situation that exists, therefore mean that there is the situation that does not meet Kirchhoff's current law (KCL) in the current signal on a plurality of total node branch roads.The current protection that now needs locking series capacitance apparatus, and investigate in time reason.
Do not need to consider the concrete state of BCB branch road owing to utilizing above-mentioned criterion to be judged, therefore can accurately judge at any time whether a plurality of total node branch current signals meet Kirchhoff's current law (KCL).What between the first criterion and Second Criterion, adopt has strengthened tightness and the reliability of this logic criterion with computing simultaneously.Owing to adopting double condition to be judged, use the first criterion and Second Criterion to carry out criterion simultaneously, therefore reduced and met
thereby the time, comprise BCB branch current signal interior two or several current signals simultaneously insincere and incredible amount distortion just in time positive and negative counteracting cause the probability that can not find that the insincere phenomenon of current signal occurs.
The one group current signal sampled data (i of logic criterion to each sampling instant
t.1～i
t.n) carry out computing and judged.
According to another specific embodiment of the present invention, in each embodiment of the control guard method of the above-mentioned series capacitance apparatus of the present invention, can use logic criterion
judge whether current signal meets Kirchhoff's current law (KCL).For example above-mentioned step 102 embodiment illustrated in fig. 1 or in above-mentioned step 202 embodiment illustrated in fig. 5, can be used logic criterion
judge whether current signal meets Kirchhoff's current law (KCL).
Another specific embodiment according to the present invention; in order further to improve the reliability and security of the control guard method of series capacitance apparatus, can adopt redundancy each other, two protective devices that function is identical to carry out respectively the control guard method of series capacitance apparatus of the present invention.Wherein two protective devices receive the current signal in a plurality of total node branch road that each current transformer measures in same sampling instant respectively independently of one another, and when the current signal of determining a plurality of total node branch roads is insincere the current protection of the apparatus of locking series capacitance independently of one another.
Two each other the protective device of redundancy can carry out respectively each specific embodiment of the control guard method of the above-mentioned series capacitance apparatus of the present invention.The flow chart of another embodiment of control guard method that Fig. 6 is series capacitance apparatus of the present invention, wherein two protective devices can be carried out the following step 301-304 independently of one another:
The structural representation of the embodiment of control protective unit that Fig. 7 is series capacitance apparatus of the present invention.The control protective unit of this embodiment can be used in the present invention the corresponding function of the control guard method of above-mentioned series capacitance apparatus.Wherein in this embodiment; the series capacitance apparatus comprises a plurality of total node branch roads; be respectively arranged with a current transformer on each total node branch road in a plurality of total node branch roads; for the current signal on the total node branch road in its place, measured; a plurality of total node branch roads comprise the bypass breaker branch road, and this control protective unit comprises:
Receiving element 701, for receiving the current signal of a plurality of total node branch road that each current transformer measures in same sampling instant respectively.
Whether recognition unit 702, meet Kirchhoff's current law (KCL) for the current signal of identifying a plurality of total node branch roads of same sampling instant.
Determining unit 703, for the recognition result according to recognition unit 702, if the current signal in a plurality of total node branch roads of same sampling instant does not meet Kirchhoff's current law (KCL), determine that the current signal in a plurality of total node branch roads is insincere.
The control protective unit of the series capacitance apparatus provided based on the above embodiment of the present invention; owing on a plurality of total node branch road that comprises the BCB branch road at the series capacitance apparatus, a TA being set respectively; thereby can measure the current signal on a plurality of total node branch roads in the series capacitance apparatus; and can utilize Kirchhoff's current law (KCL) accurately to judge that in the series capacitance apparatus, whether the current signal on a plurality of total node branch roads is credible, thereby improve the reliability and security of series capacitor unit protection.
According to a specific embodiment of the present invention, the series capacitance apparatus can be FSC, TCSC, FCL or other similar device.Wherein in Fig. 2, the series capacitance apparatus is FSC; In Fig. 3, the series capacitance apparatus is TCSC, wherein as required the GAP branch road can be arranged, and also can there is no the GAP branch road; Be FCL in Fig. 4, at least one in GAP and thyristor bypass branch wherein can be set as required.
According to another specific embodiment of the present invention, determining unit 703 in embodiment illustrated in fig. 7 is according to the recognition result of recognition unit 702, when the current signal in a plurality of total node branch roads of same sampling instant meets Kirchhoff's current law (KCL), determine that the current signal in a plurality of total node branch roads is credible.
The structural representation of another embodiment of control protective unit that Fig. 8 is series capacitance apparatus of the present invention.The control protective unit of this embodiment can be used in the present invention the function of the control guard method of above-mentioned middle series capacitance apparatus embodiment illustrated in fig. 5.Referring to Fig. 8, with the embodiment shown in Fig. 7, to compare, the control protective unit of this embodiment also comprises judging unit 801, wherein:
Judging unit 801, when insincere for the current signal of determining a plurality of total node branch roads in determining unit 703, judge whether that the current signal in M a plurality of total node branch roads of the continuous sampling moment is insincere, and the M value is the default integer that is greater than zero.If when the current signal in being less than the continuous a plurality of total node branch roads of sampling instant of M is insincere, to mean that continuous sampling numerical value accumulative total constantly adds 1, the current signal in a plurality of total node branch road that indication receiving element 701 each current transformers of reception are measured in next sampling instant respectively; If when the current signal in M a plurality of total node branch roads of the continuous sampling moment is insincere, the current protection of indication performance element 704 locking series capacitance apparatuses.
In this embodiment; in the incredible situation of current signal; cause erroneous judgement for avoiding indivedual sampling instants accidentally not meet Kirchhoff's current law (KCL), adopt the delay lock way that sends again the latch-up protection signal after M continuous sampling instant of judgement all do not meet Kirchhoff's current law (KCL).By the mode of this continuous judgement, can effectively avoid current signal accidentally not meet logic criterion and the erroneous judgement that causes in indivedual sampling instants, thereby guarantee the reliability of judgement.
According to another specific embodiment of the present invention, in the control protective unit embodiment of the above-mentioned series capacitance apparatus of the present invention, recognition unit 702 specifically can utilize logic criterion
judge whether current signal meets Kirchhoff's current law (KCL).For example Fig. 7 and embodiment illustrated in fig. 8 in recognition unit 702 in, can adopt logic criterion
judge whether current signal meets Kirchhoff's current law (KCL).Wherein when the logical value of this logic criterion be 1, mean that the first criterion and Second Criterion all set up, now mean that the current signal on a plurality of total node branch roads meets Kirchhoff's current law (KCL).And the logical value of working as this logic criterion is 0, mean in the first criterion and Second Criterion the invalid situation that exists, therefore mean that there is the situation that does not meet Kirchhoff's current law (KCL) in the current signal on a plurality of total node branch roads.
Do not need to consider the concrete state of BCB branch road owing to utilizing above-mentioned criterion to be judged, therefore can accurately judge at any time whether a plurality of total node branch current signals meet Kirchhoff's current law (KCL).What between the first criterion and Second Criterion, adopt has strengthened tightness and the reliability of this logic criterion with computing simultaneously.Owing to adopting double condition to be judged, use the first criterion and Second Criterion to carry out criterion simultaneously, therefore reduced and met
thereby the time, comprise BCB branch current signal interior two or several current signals simultaneously insincere and incredible amount distortion just in time positive and negative counteracting cause the probability that can not find that the insincere phenomenon of current signal occurs.
The structural representation of the embodiment of control protection system that Fig. 9 is series capacitance apparatus of the present invention.The control protection system of this embodiment series capacitance apparatus can be used in the present invention the flow process of the control guard method of above-mentioned series capacitance apparatus.As shown in Figure 9, control protection system and comprise platform data acquisition system 901 and the first protective device 902.The series capacitance apparatus comprises a plurality of total node branch roads simultaneously, be respectively arranged with a current transformer on each total node branch road in a plurality of total node branch roads, for the current signal on the total node branch road in its place, measured, a plurality of total node branch roads comprise the bypass breaker branch road.Wherein:
Platform data acquisition system 901, for receiving the current signal in a plurality of total node branch road that on a plurality of total node branch roads of series capacitance apparatus, TA measures in same sampling instant respectively and being processed.Platform data acquisition system 901 utilizes the equipment such as electromagnetic interface filter, signal condition unit and A/D converting unit received current signal to be carried out to the processing such as filtering, A/D conversion, and by corresponding light path, the current signal after processing is sent to first protective device 902 in control room on the spot.
The first protective device 902, the current signal sent for receiving platform data acquisition system 901; Whether the current signal of identifying in a plurality of total node branch roads of same sampling instant meets Kirchhoff's current law (KCL); If the current signal in a plurality of total node branch roads of same sampling instant does not meet Kirchhoff's current law (KCL), determine that the current signal in a plurality of total node branch roads is insincere; When the current signal in a plurality of total node branch roads is insincere, the current protection of locking series capacitance apparatus.
The control protection system of the series capacitance apparatus provided based on the above embodiment of the present invention; owing on a plurality of total node branch road that comprises the BCB branch road at the series capacitance apparatus, a TA being set respectively; thereby can measure the current signal on a plurality of total node branch roads in the series capacitance apparatus; and can utilize Kirchhoff's current law (KCL) accurately to judge that in the series capacitance apparatus, whether the current signal on a plurality of total node branch roads is credible, thereby improve the reliability and security of series capacitor unit protection.
According to a specific embodiment of the present invention, the series capacitance apparatus can be FSC, TCSC, FCL, or other similar device.Wherein in Fig. 2, the series capacitance apparatus is FSC; In Fig. 3, the series capacitance apparatus is TCSC, wherein as required the GAP branch road can be arranged, and also can there is no the GAP branch road; In Fig. 4, the series capacitance apparatus is FCL, and at least one in GAP and thyristor bypass branch wherein can be set as required.
The structural representation of another embodiment of control protection system that Figure 10 is series capacitance apparatus of the present invention.In this embodiment, control protection system and comprise platform data acquisition system 901, the first protective device 902 and operating means 903, wherein:
At first current signal is delivered to the data summarization unit 911 in the first protective device 902 with the light signal form through light path; data summarization unit 911 first converts light signal to the signal of telecommunication; and therefrom parse sampled data, then sampled data is sent to each control unit 912 and protected location 913 by the data format of making an appointment.
In practical engineering application, light path and platform data acquisition system 901 can be directly exposed to open air, and data summarization unit 911 can be arranged on ground and control in the protection cabinet.Because data summarization unit 911 is data source header that protection system is controlled on ground; its service behaviour has determined the operation conditions of a whole set of control protection system to a great extent; therefore require data summarization unit 911 to there is high speed, stable data-handling capacity, error detection to a certain degree and error correction, stronger noiseproof feature, and can provide abundant state information for self operating mode.
The current signal that the first protective device 902 provides according to platform data acquisition system 901, whether the current signal of identifying on a plurality of total node branch roads meets Kirchhoff's current law (KCL); If current signal does not meet Kirchhoff's current law (KCL), determine that the current signal in a plurality of total node branch roads is insincere; When the current signal in a plurality of total node branch roads is insincere, by the current protection of control unit 912 locking series capacitance apparatuses.
Operating means 903, for the control of the protected location 912 according to the first protective device 902, carry out the operations such as corresponding circuit breaker, disconnecting link.
According to a specific embodiment of the present invention, data summarization unit 911 or the interior execution of protected location 913 that the relevant identifying operation related in the first protective device 902 and definite operation can be in the first protective devices 902.If aforesaid operations is in the interior execution of data summarization unit 911, this computing should be last the logical operation link before current signal is sent to protected location 913.If the computing of relevant criterion is in the interior execution of protected location 913, should be first logical operation link after current signal is sent to protected location 913.
In the control protection system of the series capacitance apparatus of various embodiments of the present invention, each specific embodiment of the control protective unit that protective device specifically can be by the above-mentioned series capacitance apparatus of the present invention is realized.For example in this embodiment, the embodiment shown in the first protective device 902 concrete employing Fig. 7 of the present invention.
The structural representation of another embodiment of control protection system that Figure 11 is series capacitance apparatus of the present invention.In order further to improve the reliability of the control guard method of series capacitance apparatus, can adopt redundancy each other, two protective devices that function is identical to carry out respectively the control guard method of series capacitance apparatus of the present invention.Wherein two protective devices 902 and 922 receive the current signal in a plurality of total node branch road that each current transformer measures in same sampling instant respectively independently of one another, and the current protection of the apparatus of locking series capacitance independently of one another when insincere of the current signal on determining a plurality of total node branch roads.Each specific embodiment of two control protective units that the protective device 902 and 922 of redundancy specifically can be by the above-mentioned series capacitance apparatus of the present invention is each other realized.Embodiment illustrated in fig. 11ly take series capacitance apparatus embodiment illustrated in fig. 12 and describe as example.
Referring to Figure 11; with the embodiment shown in Figure 10, compare; this embodiment is except the first protective device 902, operating means 903 and platform data acquisition system 901; also have respectively the second protective device 922 and platform data acquisition system 921 with the first protective device 902 and platform data acquisition system 901 mutual redundancies, the functions of the equipments of redundancy are identical mutually.The secondary side of measuring TA has two passages, and measurement data is passed through respectively these two channel transfer to platform data acquisition system 901 and 921.Current signal after the processing such as platform data acquisition system 901 and 921 respectively will be after filtering, A/D conversion sends to the first protective device 902 and the second protective device 922.The first protective device 902 and the second protective device 922 receive the current signal in a plurality of total node branch road that each current transformer measures in same sampling instant respectively independently of one another, and the current protection of the apparatus of locking series capacitance independently of one another when insincere of the current signal on determining a plurality of total node branch roads.
To be FSC illustrate this embodiment of the invention as example the series capacitance apparatus of below take.
Figure 12 is the structural representation when series capacitance apparatus is FSC according to the present invention.Include the current transformer TA1～TA7 installed on series capacitor bank, two metal oxide pressure-limiting device MOV1 and MOV2, damping device D, spark gap GAP, bypass breaker BCB and each key equipment place branch road and series circuit branch road at this FSC.Series capacitor adopts single H type mode of connection.
In Figure 12, getting node A is that the numbering of each branch road is identical with the numbering of each branch current instrument transformer with reference to node, and getting the direction that flows into node A is positive direction.The sampled signal of series circuit branch current, capacitor bank branch current, the poor branch current of capacitor bridge, MOV1 branch current, MOV2 branch current, GAP branch current, BCB branch current is followed successively by i
t.1, i
t.2, i
t.3, i
t.4, i
t.5, i
t.6, i
t.7.Two cover acquisition systems respectively should corresponding two cover sampled signal, i.e. i
t.A1～i
t.A7and i
t.B1～i
t.B7.
The present embodiment is determined the interior realization of the data summarization unit in protective device 902 and 922 911 respectively of the whether believable function of current signal.Also in the protected location in protective device 902 and 922 913, realize respectively.
Make i
kCLfor the algebraical sum of the corresponding all branch current sampled values of node A, the present embodiment judges the current signal on each total node branch road, that is: i
t.1, i
t.2, i
t.4, i
t.5, i
t.6, i
t.7, whether believable criterion be (| i
kCL|≤δ ') & (|| i
kCL-i
t.7|-| i
t.7||≤δ ').δ ' can and obtain with reference to empirical value by a large amount of test recorder datas or on-the-spot service data.Cause erroneous judgement for avoiding under the current signal trustworthy information indivedual sampling instants accidentally not meet this criterion, the present embodiment is got the parameter M=5 of delay lock.
Calculate i in the first protective device 902
kCL.A=i
t.A1+ i
t.A2+ i
t.A4+ i
t.A5+ i
t.A6+ i
t.A7, and judge whether to meet criterion A:(|i
kCL.A|≤δ ') & (|| i
kCL.A-i
t.A7|-i
t.A7||≤δ '); Calculate i simultaneously in the second protective device 922
kCL.B=i
t.B1+ i
t.B2+ i
t.B4+ i
t.B5+ i
t.B6+ i
t.B7, and judge whether to meet criterion B:(|i
kCL.B|≤δ ') & (|| i
kCL.B-i
t.B7|-| i
t.B7||≤δ ').Following three kinds of judged results should be arranged:
1) if in two protective devices, current signal all meets corresponding criterion, shows that the signal that two protective devices receive is all credible.
2) if therein in protective device; current signal on a plurality of total node branch roads of continuous 5 sampling instants does not all meet corresponding criterion; showing has one or more current signals insincere in the current signal on a plurality of total node branch road that this protective device receives; the control unit 912 latching current protections of this protective device, and in time according to the incredible reason of recorder data investigation current signal.If certain component wear in platform data acquisition system or protective device and causing, can exit this protection system and change and damage element.And meeting the protective device of corresponding criterion, another current signal normally moves.
3) if in two protective devices; measuring-signal on a plurality of total node branch roads of continuous 5 sampling instants all is discontented with and is enough to corresponding criterion; show that the current signal on two protective devices of redundancy receive each other a plurality of total node branch road is all insincere, each other the control unit 912 latching currents protections in two of redundancy protective devices.
It may be noted that the probability occurred due to the third situation is lower, therefore in the situation that exist the insincere and system of current signal to have fault to occur, still can realize each series capacitance apparatus is controlled to protection.
Description of the invention provides for example with for the purpose of describing, and is not exhaustively or limit the invention to disclosed form.Many modifications and variations are obvious for the ordinary skill in the art.Selecting and describing embodiment is for better explanation principle of the present invention and practical application, thereby and makes those of ordinary skill in the art can understand the various embodiment with various modifications that the present invention's design is suitable for special-purpose.
Claims (17)
1. the control guard method of a series capacitance apparatus; it is characterized in that; described series capacitance apparatus comprises a plurality of total node branch roads; be respectively arranged with a current transformer on each total node branch road in described a plurality of total node branch road; for the current signal on the total node branch road in its place, measured; described a plurality of total node branch road comprises the bypass breaker branch road, and the method comprises:
Receive each current transformer current signal in the described a plurality of total node branch road of same sampling instant measurement respectively;
Whether the current signal of identifying in the described a plurality of total node branch roads of same sampling instant T meets the first criterion simultaneously
with Second Criterion
wherein, the number that n is described a plurality of total node branch roads, i
t.ifor the current signal on i branch road of sampling instant T, subscript i is greater than zero and be not more than the integer of n, and δ is the default numerical value that is greater than zero; If meet the first criterion and Second Criterion when the current signal in the described a plurality of total node branch roads of same sampling instant T is different, think that the current signal in the described a plurality of total node branch roads of same sampling instant T does not meet Kirchhoff's current law (KCL);
If the current signal in the described a plurality of total node branch roads of same sampling instant does not meet Kirchhoff's current law (KCL), determine that the current signal in described a plurality of total node branch road is insincere;
When the current signal in described a plurality of total node branch roads is insincere, the current protection of the described series capacitance apparatus of locking.
2. method according to claim 1, is characterized in that,
If the current signal in the described a plurality of total node branch roads of same sampling instant T meets the first criterion and Second Criterion simultaneously, think that the current signal in the described a plurality of total node branch roads of same sampling instant T meets Kirchhoff's current law (KCL).
3. method according to claim 2, is characterized in that, if the current signal in the described a plurality of total node branch roads of same sampling instant meets Kirchhoff's current law (KCL), determines that the current signal in described a plurality of total node branch road is credible.
4. according to the described method of any one in claim 1-3, it is characterized in that, after the current signal in described definite described a plurality of total node branch roads is insincere, also comprise:
Judge whether that the current signal in M described a plurality of total node branch roads of the continuous sampling moment is insincere, the M value is the default integer that is greater than zero;
When described current signal in described a plurality of total node branch roads is insincere; the current protection of the described series capacitance apparatus of locking comprises: when the current signal in M described a plurality of total node branch roads of the continuous sampling moment is insincere, and the current protection of the described series capacitance apparatus of locking.
5. according to the described method of any one in claim 1-3; it is characterized in that; described method by two, carry out respectively each other by redundancy, protective device that function is identical; wherein protective device receives the current signal in the described a plurality of total node branch road that each current transformer measures in same sampling instant independently of one another, and when determining that current signal is insincere the current protection of the described series capacitance apparatus of locking independently of one another.
6. according to the described method of any one in claim 1-3, it is characterized in that, described series capacitance apparatus is fixed series capacitors compensation arrangement, thyristor controlled series capacitor compensation arrangement or series resonant-type fault current limiter device.
7. the control protective unit of a series capacitance apparatus; described series capacitance apparatus comprises a plurality of total node branch roads; be respectively arranged with a current transformer on each total node branch road in described a plurality of total node branch road; for the current signal on the total node branch road in its place, measured; described a plurality of total node branch road comprises the bypass breaker branch road, and this control protective unit comprises:
Receiving element, for receiving the current signal of described a plurality of total node branch roads that each current transformer measures in same sampling instant respectively;
Whether recognition unit, meet the first criterion for the current signal of identifying the described a plurality of total node branch roads of same sampling instant T simultaneously
with Second Criterion
wherein, the number that n is described a plurality of total node branch roads, i
t.ifor the current signal on i branch road of sampling instant T, subscript i is greater than zero and be not more than the integer of n, and δ is the default numerical value that is greater than zero; If meet the first criterion and Second Criterion when the current signal in the described a plurality of total node branch roads of same sampling instant T is different, think that the current signal in the described a plurality of total node branch roads of same sampling instant T does not meet Kirchhoff's current law (KCL);
Determining unit, for the recognition result according to described recognition unit, if the current signal in the described a plurality of total node branch roads of same sampling instant does not meet Kirchhoff's current law (KCL), determine that the current signal in described a plurality of total node branch road is insincere;
Performance element, when insincere for the current signal of determining described a plurality of total node branch roads in described determining unit, the current protection of the described series capacitance apparatus of locking.
8. device according to claim 7, it is characterized in that, when described recognition unit also meets the first criterion and Second Criterion for the current signal at the described a plurality of total node branch roads of same sampling instant T simultaneously, think that the current signal in the described a plurality of total node branch roads of same sampling instant T meets Kirchhoff's current law (KCL).
9. device according to claim 8, it is characterized in that, described determining unit is also according to the recognition result of described recognition unit, if the current signal in the described a plurality of total node branch roads of same sampling instant meets Kirchhoff's current law (KCL), determine that the current signal in described a plurality of total node branch roads is credible.
10. according to the described device of any one in claim 7-9; it is characterized in that; also comprise judging unit; insincere for judging whether at the current signal of M described a plurality of total node branch roads of the continuous sampling moment; the M value is the default integer that is greater than zero; if the current signal in M described a plurality of total node branch roads of the continuous sampling moment is insincere, indicate the current protection of the described series capacitance apparatus of described performance element locking.
11. according to the described device of any one in claim 7-9, it is characterized in that, described series capacitance apparatus is fixed series capacitors compensation arrangement, thyristor controlled series capacitor compensation arrangement or series resonant-type fault current limiter device.
12. the control protection system of a series capacitance apparatus, it is characterized in that, described series capacitance apparatus comprises a plurality of total node branch roads, be respectively arranged with a current transformer on each total node branch road in described a plurality of total node branch road, for the current signal on the total node branch road in its place, measured, described a plurality of total node branch road comprises the bypass breaker branch road, and this control protection system comprises platform data acquisition system and the first protective device;
Described platform data acquisition system, carry out filtering, analog-to-digital conversion for the current signal of the described a plurality of total node branch roads to measuring in same sampling instant respectively from each current transformer, and the current signal after processing sent to the first protective device;
Described the first protective device, the current signal sent for receiving described platform data acquisition system; Whether the current signal of identifying in the described a plurality of total node branch roads of same sampling instant T meets the first criterion simultaneously
with Second Criterion
wherein, the number that n is described a plurality of total node branch roads, i
t.ifor the current signal on i branch road of sampling instant T, subscript i is greater than zero and be not more than the integer of n, and δ is the default numerical value that is greater than zero; If meet the first criterion and Second Criterion when the current signal in the described a plurality of total node branch roads of same sampling instant T is different, think that the current signal in the described a plurality of total node branch roads of same sampling instant T does not meet Kirchhoff's current law (KCL); If the current signal in the described a plurality of total node branch roads of same sampling instant does not meet Kirchhoff's current law (KCL), determine that the current signal in described a plurality of total node branch road is insincere; When the current signal in described a plurality of total node branch roads is insincere, the current protection of the described series capacitance apparatus of locking.
13. system according to claim 12, is characterized in that, described the first protective device is specially the control protective unit of the described series capacitance apparatus of any one in claim 7-10.
14. system according to claim 12, is characterized in that, the series capacitance apparatus is fixed series capacitors compensation arrangement, thyristor controlled series capacitor compensation arrangement or series resonant-type fault current limiter device.
15. system according to claim 14, is characterized in that, the thyristor controlled series capacitor compensation arrangement comprises the spark gap branch road.
16. system according to claim 14, is characterized in that, the series resonant-type fault current limiter device comprises at least one in spark gap branch road and thyristor bypass branch.
17. system according to claim 12; it is characterized in that; described system also comprises and described the first protective device the second protective device of redundancy each other; described the second protective device is identical with described the first protective device function; described the first protective device and the second protective device receive the current signal in the described a plurality of total node branch road that each current transformer measures in same sampling instant respectively independently of one another, and the current protection of the described series capacitance apparatus of locking independently of one another when insincere of the current signal on determining described a plurality of total node branch roads.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110192299.1A CN102244379B (en) | 2011-07-11 | 2011-07-11 | Method, device and system for controlling and protecting serial capacitors |
| BR112014000646A BR112014000646A2 (en) | 2011-07-11 | 2012-06-29 | METHOD, DEVICE AND CONTROL PROTECTION SYSTEM FOR SERIAL CAPACITOR DEVICE |
| PCT/CN2012/077820 WO2013007151A1 (en) | 2011-07-11 | 2012-06-29 | Control protection method, device and system for series capacitor device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110192299.1A CN102244379B (en) | 2011-07-11 | 2011-07-11 | Method, device and system for controlling and protecting serial capacitors |
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| Publication Number | Publication Date |
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| CN102244379A CN102244379A (en) | 2011-11-16 |
| CN102244379B true CN102244379B (en) | 2013-12-25 |
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| CN (1) | CN102244379B (en) |
| BR (1) | BR112014000646A2 (en) |
| WO (1) | WO2013007151A1 (en) |
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| CN102244379B (en) * | 2011-07-11 | 2013-12-25 | 中电普瑞科技有限公司 | Method, device and system for controlling and protecting serial capacitors |
| CN105652685B (en) * | 2014-11-14 | 2018-11-27 | 国家电网公司 | A kind of dynamic simulation experiment function simulator |
| CN108776270A (en) * | 2018-04-18 | 2018-11-09 | 云南电网有限责任公司怒江供电局 | A kind of series compensation platform fault locator |
| CN109901004B (en) * | 2019-02-20 | 2021-02-23 | 北京航空航天大学 | Method and system for detecting short circuit in vehicle-mounted power battery |
| CN111896866A (en) * | 2020-07-06 | 2020-11-06 | 广东电网有限责任公司 | Method and device for detecting disconnecting link of hot bus-bar reversing operation bus |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101162851A (en) * | 2007-09-30 | 2008-04-16 | 常熟理工学院 | Controller of low pressure intelligent type circuit breakers with mutual verifying function |
| CN101789602A (en) * | 2010-01-13 | 2010-07-28 | 中国电力科学研究院 | Dynamic simulation device of extra-high, ultrahigh voltage thyristor controlled series compensation device and test method thereof |
| CN201805235U (en) * | 2010-09-20 | 2011-04-20 | 中电普瑞科技有限公司 | Extra/ultra-high voltage series capacitor compensating device having current transfer branch circuit |
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| DE59203773D1 (en) * | 1992-05-20 | 1995-10-26 | Siemens Ag | Method and device for detecting defects in a control system of a controlled series compensator. |
| CN102064527B (en) * | 2010-12-24 | 2014-03-12 | 中电普瑞科技有限公司 | Control and protection system of series compensation device or fault current limiter |
| CN102231515B (en) * | 2011-07-11 | 2013-11-13 | 中电普瑞科技有限公司 | Control protection method, device and system for series capacitor device |
| CN102244379B (en) * | 2011-07-11 | 2013-12-25 | 中电普瑞科技有限公司 | Method, device and system for controlling and protecting serial capacitors |
-
2011
- 2011-07-11 CN CN201110192299.1A patent/CN102244379B/en active Active
-
2012
- 2012-06-29 BR BR112014000646A patent/BR112014000646A2/en not_active Application Discontinuation
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101162851A (en) * | 2007-09-30 | 2008-04-16 | 常熟理工学院 | Controller of low pressure intelligent type circuit breakers with mutual verifying function |
| CN101789602A (en) * | 2010-01-13 | 2010-07-28 | 中国电力科学研究院 | Dynamic simulation device of extra-high, ultrahigh voltage thyristor controlled series compensation device and test method thereof |
| CN201805235U (en) * | 2010-09-20 | 2011-04-20 | 中电普瑞科技有限公司 | Extra/ultra-high voltage series capacitor compensating device having current transfer branch circuit |
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|---|---|
| WO2013007151A1 (en) | 2013-01-17 |
| CN102244379A (en) | 2011-11-16 |
| BR112014000646A2 (en) | 2022-09-06 |
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