CN104330708B - Fault location method for wide area traveling wave signal below power grid - Google Patents

Abstract

The invention discloses a fault location method for wide area traveling wave signal below power grid, with a little of fault traveling wave monitoring points for the power grid, the fault signal is processed on the phase-mode transformation and the small wave mode maximum value process to obtain the initial wave header information; the extension double-end travelling wave fault location is realized in the complex power grid, the fault location method of general power grid is offered on this basis for fast finding the exact double-end ranging combination from the measured data, and raising the ranging precision by amending the result. The monitoring data is processed and checked for realizing extension double-end travelling wave fault location for any fault point of the system, and the method has good fault-tolerant capability.

Description

The Fault Locating Method of wide area travelling wave signal under general electrical network

Technical field

The present invention relates to being adapted to the Fault Locating Method research of wide area travelling wave signal under general electrical network.

Background technology

Spatial dimension with modern power systems constantly expands and modern computer treatment technology, Digital Signal Processing skill When art, GPS synchronization school, technology is growing, and the Wide-area Measurement Information collection after complex electric network fault is more and more easily realized.For Relay protection under wide area system and status monitoring research also gradually increase；For reducing failure accident loss, the economy having reached Effect and social benefit, will be monitored to the safe condition of electrical network, and fault is quickly positioned, particularly with wide area system System, has occurred in that some ripe achievements in research both at home and abroad.Due to traveling wave method affected by the change of system operational parameters less, And more difficult to the identification of back wave in view of single end distance measurement method, the scope of application of some Improving ways is also less^[1][2], because This utilizes the time-frequency local characteristicses of small echo, the initial wave head due in of transient state travelling wave is detected, and then is surveyed using both-end Found range away from method.The device that this direct use traveling wave Monitoring Data is found range is referred to as TWR (Traveling Waves Recorder).

To under wide area system Fault Location With Traveling Wave research in, its algorithm mainly for radial distribution networks, if in system Containing special constructions such as looped networks, then algorithm effect may just not reach desirable；Asked for using neighbor point optimisation strategy Short path, then obtains abort situation by linear regression analysis；Document^[5]In the case of the Conceptual Extension by both-end distance measuring, Calculate the time reaching all monitoring points when each bar bus breaks down, to reach the minimum of detection means when physical fault occurs Based on time, finally norm calculation is carried out to detected value and theoretical value, select the minimum corresponding bus of two norms, enter And determine faulty line, but, this method is limited to the design feature of circuit, can only meet IEEE-14 system 82.2% Circuit, and rapidly can not be automatically separated the circuit that is out of order, need artificially to be analyzed；Document^[3,4]Using complex electric network Wide area traveling wave information realization fault location it is contemplated that in electrical network TWR allocation problem, but do not account for the fault-tolerant of its algorithm Property.

Bibliography

[1] Zhang Linli, Xu Bingyin, Xue Yongduan etc. the low current grounding transient state based on line voltage and zero mould electric current is fixed Method for position [J]. Proceedings of the CSEE, 2012,32 (13):110-115.

[2] Tang Jinrui, Yin Xianggen, Zhang Zhe etc. zero mould detects the iterative extraction of wave velocity and its in power distribution network single-phase earthing Application [J] in fault location. electrotechnics journal, 2013,28 (4):202-211.

[3]MertKorkali,Hanoch Lev-Ari,Ali Abur.Traveling-Wave-Based Fault- Location Technique for Transmission Grids Via Wide-Area Synchronized Voltage Measurements[J].IEEE Trans.Power Del.,May 2012,27(2):1003-1011.

[4]Korkali M,Abur A.Optimal deployment of wide-area synchronized measurements for fault-location observability[J].Power Systems,IEEE Transactions on,2013,28(1):482-489.

[5]M.Korkali,A.Abur.Fault location in meshed power networks using synchronized measurements.Proc.North American Power Symp.,Sep.2010:1-6.

Content of the invention

Goal of the invention：In order to overcome the deficiencies in the prior art, the present invention provides wide area row under a kind of general electrical network The Fault Locating Method of ripple signal, can realize to Arbitrary Fault point in system extending both-end travelling wave ranging, have good appearance Wrong ability.

Technical scheme：For achieving the above object, the technical solution used in the present invention is：

1st, under a kind of general electrical network wide area travelling wave signal Fault Locating Method, comprise the steps：

1) select optimal T WR allocation plan in the electrical network that topological structure determines, obtain priori；Described priori Including the beeline between bus nodes all in electrical network, the TWR corresponding bus position of configuration, install at the bus of TWR One or more adjacent bus and described one or more adjacent bus arrive separately at the beeline of each TWR, line mould Traveling wave spread speed c_a；Described priori is stored in database SQL -0；

2) assume to configure K TWR in electrical network, when breaking down in electrical network, K TWR is detected simultaneously by fault traveling wave voltage, The time T that the initial wavefront of fault reaches K TWR is obtained by modular transformation and wavelet transformation_Mn(n=1～K), n is n-th TWR；In T_MnMinimum of a value T is found in (n=1～K)_minIt is known that T_minThe installation bus position I of corresponding TWR_i；By inquiry Database SQL -0 is it is known that bus I_iP bar adjacent bus I_vj(j=1～p)；Understand adjacent bus I_vj(j=1～p) arrives respectively Reach beeline D of K TWR_vj(j=1～p)；

3) make bus I_iThe TWR at place constitutes both-end travelling wave ranging with other K-1 TWR respectively and combines, and arbitrarily selects I_iOne Bar adjacent bus I_vj(j=1～p), arranges initial j=1；Wherein carry out during both-end travelling wave ranging using comprising this adjacent bus Arrive separately at the beeline of K TWR；K group fault message, described fault message be can be calculated according to both-end travelling wave ranging technology For faulty line R_Mt(t=1～K) and faulty line R_MtThe fault distance S of (t=1～K) upper distance line head end_Mt(t=1～ K)；T is t group fault message；

4) initially make t=1, arbitrarily select one group of faulted-phase judgment：I.e. according to the faulty line R in this group_Mt(t=1～ K) corresponding fault distance S_Mt(t=1～K) determines one of corresponding electrical network position of failure point, by this trouble point position Put as new node f；

5) according to the fault distance S in this group fault message selected_Mt(t=1～K), inquiry database SQL -0 understands New node f is to each TWR apart from S_f, according to new node f to each TWR apart from S_fNew node f can be obtained to each TWR's Transmission time T_f；

6) calculate T_Mn(n=1～K) and transmission time T_fManhatton distance：H_n=| | T_f—T_Mn| | (n=1～K)；

7) judge step 4)～step 6) in K group fault message whether be all disposed, that is, whether t=K sets up, if become Vertical, then enter step 8)；If not, t=t+1, return to step 4)；

8) K group manhatton distance can be obtained according to above step, find manhatton distance in K group manhatton distance minimum Value：ΔT_j=minH (j=1～p), and record the corresponding fault distance of this minimum of a value, faulty line and both-end travelling wave ranging Combination, the data being recorded is stored in database SQL -1；

9) repeat step 3)～step 8), obtain the minimum manhatton distance minimum of a value corresponding to every adjacent bus；I.e. j Whether=p sets up, if set up entering step 10)；If being false, j=j+1, return to step 3)；

10) minimum manhatton distance set is constituted by each corresponding manhatton distance minimum of a value of the adjacent bus of p bar：Δ T=[Δ T₁ΔT₂...ΔT_p]；Find the minimum of a value in Δ T, inquiry database SQL -1 obtains the fault corresponding to this minimum of a value Distance, faulty line and the both-end travelling wave ranging combination being used, the combination of both-end travelling wave ranging is assumed to be T_minAnd T_K, by public affairs Formula (T_min-t₀)c_a+(T_K-t₀)c_a=L_iKObtain time of failure t₀, wherein L_iKRepresent that the combination of this both-end travelling wave ranging is used Beeline；

11) according to S_i=c_a(T_Mn–t₀), obtain actual fault point to each TWR apart from S_i, then moved towards by respective lines Inquiry database SQL -0, the physical fault obtaining offline road head end on the physical fault circuit that each TWR records is apart from S_fact= {S_facti, i=1～K }；

12) to result S_factTest：If physical fault is apart from S_fact={ S_facti, i=1～K } and for bearing or being more than Respective lines length or physical fault are apart from S_fact={ S_facti, i=1～K } in data be unsatisfactory for 3 σ criterions, all delete corresponding real Border fault distance data；Assume finally also have m group physical fault range data composition to calculate data groupFinally measured Fault distance is:

Beneficial effect：

The present invention seeks in the case of the configured a small amount of fault traveling wave monitoring point of electrical network, the phase of signal after to fault Modular transformation and Wavelet Modulus Maxima process and obtain primary wave header.Consider to realize extension both-end traveling wave under complex electric network situation Range finding, provides general electric network fault localization method on this basis, realizes fast searching from measurement data and goes out accurate traveling wave Range finding combination, improves, by revising of result, the precision found range.And by process and the inspection of Monitoring Data it is ensured that to system Middle Arbitrary Fault point can be realized extending both-end travelling wave ranging, has good fault-tolerant ability.

Brief description

Fig. 1 is the flow chart of Fault Locating Method；

Fig. 2 is I_iAdjacent bus schematic diagram；

Fig. 3 is IEEE-30 modular system.

Specific embodiment

Below in conjunction with the accompanying drawings the present invention is further described.

1st, under a kind of general electrical network wide area travelling wave signal Fault Locating Method, comprise the steps：

1) select optimal T WR allocation plan in the electrical network that topological structure determines, obtain priori；Described priori Including the beeline between bus nodes all in electrical network, the TWR corresponding bus position of configuration, install at the bus of TWR One or more adjacent bus and described one or more adjacent bus arrive separately at the beeline of each TWR, line mould Traveling wave spread speed c_a；Described priori is stored in database SQL -0；

2) assume to configure K TWR in electrical network, when breaking down in electrical network, K TWR is detected simultaneously by fault traveling wave voltage, The time T that the initial wavefront of fault reaches K TWR is obtained by modular transformation and wavelet transformation_Mn(n=1～K), n is n-th TWR；In T_MnMinimum of a value T is found in (n=1～K)_minIt is known that T_minThe installation bus position I of corresponding TWR_i；By inquiry Database SQL -0 is it is known that bus I_iP bar adjacent bus I_vj(j=1～p)；Understand adjacent bus I_vj(j=1～p) arrives respectively Reach beeline D of K TWR_vj(j=1～p)；

3) make bus I_iThe TWR at place constitutes both-end travelling wave ranging with other K-1 TWR respectively and combines, and arbitrarily selects I_iOne Bar adjacent bus I_vj(j=1～p), arranges initial j=1；Wherein carry out during both-end travelling wave ranging using comprising this adjacent bus Arrive separately at the beeline of K TWR；K group fault message, described fault message be can be calculated according to both-end travelling wave ranging technology For faulty line R_Mt(t=1～K) and faulty line R_MtThe fault distance S of (t=1～K) upper distance line head end_Mt(t=1～ K)；T is t group fault message；

4) initially make t=1, arbitrarily select one group of faulted-phase judgment：I.e. according to the faulty line R in this group_Mt(t=1～ K) corresponding fault distance S_Mt(t=1～K) determines one of corresponding electrical network position of failure point, by this trouble point position Put as new node f；

5) according to the fault distance S in this group fault message selected_Mt(t=1～K), inquiry database SQL -0 understands New node f is to each TWR apart from S_f, according to new node f to each TWR apart from S_fNew node f can be obtained to each TWR's Transmission time T_f；

6) calculate T_Mn(n=1～K) and transmission time T_fManhatton distance：H_n=| | T_f—T_Mn| | (n=1～K)；

7) judge step 4)～step 6) in K group fault message whether be all disposed, that is, whether t=K sets up, if become Vertical, then enter step 8)；If not, t=t+1, return to step 4)；

8) K group manhatton distance can be obtained according to above step, find manhatton distance in K group manhatton distance minimum Value：ΔT_j=minH (j=1～p), and record the corresponding fault distance of this minimum of a value, faulty line and both-end travelling wave ranging Combination, the data being recorded is stored in database SQL -1；

9) repeat step 3)～step 8), obtain the minimum manhatton distance minimum of a value corresponding to every adjacent bus；I.e. j Whether=p sets up, if set up entering step 10)；If being false, j=j+1, return to step 3)；

10) minimum manhatton distance set is constituted by each corresponding manhatton distance minimum of a value of the adjacent bus of p bar：Δ T=[Δ T₁ΔT₂...ΔT_p]；Find the minimum of a value in Δ T, inquiry database SQL -1 obtains the fault corresponding to this minimum of a value Distance, faulty line and the both-end travelling wave ranging combination being used, the combination of both-end travelling wave ranging is assumed to be T_minAnd T_K, by public affairs Formula (T_min-t₀)c_a+(T_K-t₀)c_a=L_iKObtain time of failure t₀, wherein L_iKRepresent that the combination of this both-end travelling wave ranging is used Beeline；

11) according to S_i=c_a(T_Mn–t₀), obtain actual fault point to each TWR apart from S_i, then moved towards by respective lines Inquiry database SQL -0, the physical fault obtaining offline road head end on the physical fault circuit that each TWR records is apart from S_fact= {S_facti, i=1～K }；

12) to result S_factTest：If physical fault is apart from S_fact={ S_facti, i=1～K } and for bearing or being more than Respective lines length or physical fault are apart from S_fact={ S_facti, i=1～K } in data be unsatisfactory for 3 σ criterions, all delete corresponding real Border fault distance data；Assume finally also have m group physical fault range data composition to calculate data groupFinally measured Fault distance is:

The effect assessment of scheme：

Herein on the basis of specified TWR allocation plan, a kind of wide area new traveling wave location algorithm is proposed.Allocation plan can Realize system maximum considerable, that is, during any line failure, at least there is a pair of TWR can carry out both-end distance measuring to it.Now with As a example one model：

For the fault-tolerant ability of verification algorithm, assume initially that the equal normal work of TWR in system, carry out fault by ranging step Positioning, then artificially arrange fault TWR, inspection TWR cannot normal work when algorithm correctness.

This example uses IEEE-30 modular system, as shown in Figure 3.TWR configuration bus position is：2,3,5,8,11,13, 14,16,18,21,26,29,30.

Setting faulty line is circuit 46, and fault occurs at distance 4 bus 25km, and fault type is set to alternate short Road fault.Time of failure is 20ms.Note：In example, line length unit uses km, does not use English unit；In addition, it is high Frequently offline mould spread speed c_a=299.15km/s.

Error-free received data situation

The initial wavefront of fault reaches the time T of 13 TWR_MAs shown in table 1 below：

The each TWR of table 1 detects initial traveling wave arrival time

Understand from TWR Monitoring Data, T_min=t₁₃.Combined with the range finding of No. 13 TWR by other TWR and obtain every group of result As shown in table 2 below：

Table 2 fault localization PRELIMINARY RESULTS

In table, minimum No. 13 TWR of manhatton distance are combined with No. 30 TWR's, therefore, with No. 13 and No. 30 surveys obtaining Away from result as the later basis calculating, obtain fault and calculate fault time t on circuit 4-6 away from No. 4 bus 25.0729km₀ For 20.0004ms, the physical fault time is 20ms, and absolute error is 0.42 μ s.Afterwards, with fault time t₀As calculating number According to obtaining the fault distance that each TWR records as shown in table 3 below：

Fault distance after table 3 correction

Finally, calculate data mean value to obtain fault at 4 bus 25.0169km, absolute error is on circuit 4-6 16.90m.Relative error is 0.07%.

Fault-tolerant ability is verified

For verifying the fault-tolerant ability of this algorithm, on the basis of upper example, to the TWR setting mistake prison on 5,16, No. 26 buses Measured value：22.9730ms、22.5050ms、25.5770ms.

Minimum time remains t₁₃, the corresponding TWR of No. 13 buses of correspondence.By correction algorithm step, obtain step 9) try to achieve Database SQL -1 data, as shown in table 4 below：

Table 4 fault localization PRELIMINARY RESULTS

Visible according to data in table, the TWR on 5,16, No. 26 buses records fault distance and is ∞, such following steps When selecting minimum manhatton distance, the Monitoring Data of these three TWR will be deleted, proceed to analyze using remaining data.Finally Obtain the fault distance S that each TWR records_fact, as shown in table 5 below：

Fault distance after table 5 correction

Finally, obtaining fault is：Away from 4 bus 25.0006km on circuit 4-6, absolute error is 0.63m.Through simulating, verifying, Compared to other location algorithms, the method positioning precision is high, can be suitable for any type of electrical network, and have fault-tolerant well Ability.

The above be only the preferred embodiment of the present invention it should be pointed out that：Ordinary skill people for the art For member, under the premise without departing from the principles of the invention, some improvements and modifications can also be made, these improvements and modifications also should It is considered as protection scope of the present invention.

Claims (1)

1. under a kind of general electrical network wide area travelling wave signal Fault Locating Method it is characterised in that：Comprise the steps：

1) select optimal T WR allocation plan in the electrical network that topological structure determines, obtain priori；Described priori includes Beeline between all bus nodes in electrical network, the TWR corresponding bus position of configuration, at the bus of TWR is installed Bar or a plurality of adjacent bus and described one or more adjacent bus arrive separately at the beeline of each TWR, line line ripple Spread speed c_a；Described priori is stored in database SQL -0；

2) assume to configure K TWR in electrical network, when breaking down in electrical network, K TWR is detected simultaneously by fault traveling wave voltage, passes through Modular transformation and wavelet transformation obtain the time T that the initial wavefront of fault reaches K TWR_Mn(n=1～K), n is n-th TWR； In T_MnMinimum of a value T is found in (n=1～K)_minIt is known that T_minThe installation bus I of corresponding TWR_iPosition；By inquiring about data Storehouse SQL-0 is it is known that bus I_iP bar adjacent bus I_vj(j=1～p)；Understand adjacent bus I_vj(j=1～p) arrives separately at K Beeline D of TWR_vj(j=1～p)；

3) make bus I_iThe TWR at place constitutes both-end travelling wave ranging with other K-1 TWR respectively and combines, and arbitrarily selects I_iA phase Adjacent bus I_vj(j=1～p), arranges initial j=1；Wherein carry out during both-end travelling wave ranging using comprising this adjacent bus respectively Reach K TWR beeline；K group fault message be can be calculated according to both-end travelling wave ranging technology, described fault message is Faulty line R_Mt(t=1～K) and faulty line R_MtThe fault distance S of (t=1～K) upper distance line head end_Mt(t=1～K)； T is t group fault message；

4) initially make t=1, arbitrarily select one group of faulted-phase judgment：I.e. according to the faulty line R in this group_Mt(t=1～K) with Its corresponding fault distance S_Mt(t=1～K) determines one of corresponding electrical network position of failure point, and this position of failure point is made For new node f；

5) according to the fault distance S in this group fault message selected_Mt(t=1～K), inquiry database SQL -0 understands new saving Point f is to each TWR apart from S_f, according to new node f to each TWR apart from S_fThe transmission of new node f to each TWR can be obtained Time T_f；

6) calculate T_Mn(n=1～K) and transmission time T_fManhatton distance：H_n=| | T_f—T_Mn| | (n=1～K)；

7) judge step 4)～step 6) in K group fault message whether be all disposed, that is, whether t=K sets up, if so, then Enter step 8)；If not, t=t+1, return to step 4)；

8) K group manhatton distance can be obtained according to above step, find manhatton distance minimum of a value in K group manhatton distance：ΔT_j =minH (j=1～p), and record the corresponding fault distance of this minimum of a value, faulty line and the combination of both-end travelling wave ranging, will The data of its record is stored in database SQL -1；

9) repeat step 3)～step 8), obtain the minimum manhatton distance minimum of a value corresponding to every adjacent bus；I.e. j=p Whether set up, if set up entering step 10)；If being false, j=j+1, return to step 3)；

10) minimum manhatton distance set is constituted by each corresponding manhatton distance minimum of a value of the adjacent bus of p bar：Δ T= [ΔT₁ΔT₂...ΔT_p]；Find the minimum of a value in Δ T, inquiry database SQL -1 obtain fault corresponding to this minimum of a value away from From, faulty line and the both-end travelling wave ranging combination that used, the combination of both-end travelling wave ranging is assumed to be T_minAnd T_K, by formula (T_min-t₀)c_a+(T_K-t₀)c_a=L_iKObtain time of failure t₀, wherein L_iKRepresent used by the combination of this both-end travelling wave ranging Beeline；

11) according to S_i=c_a(T_Mn–t₀), obtain actual fault point to each TWR apart from S_i, then move towards to inquire about by respective lines Database SQL -0, the physical fault obtaining offline road head end on the physical fault circuit that each TWR records is apart from S_fact={ S_facti, I=1～K }；

12) to result S_factTest：If physical fault is apart from S_fact={ S_facti, i=1～K } and for bearing or being more than corresponding line Road length or physical fault are apart from S_fact={ S_facti, i=1～K } in data be unsatisfactory for 3 σ criterions, all delete corresponding physical fault Range data；Assume finally also have m group physical fault range data composition to calculate data groupFinally measured fault away from From for:

$S=\frac{1}{m}\underset{i=1}{\overset{m}{\Σ}}{S}_{facti}^{*}.$