CN103105563A - Electric power line fault traveling wave network locating method - Google Patents
Electric power line fault traveling wave network locating method Download PDFInfo
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- CN103105563A CN103105563A CN2013100325206A CN201310032520A CN103105563A CN 103105563 A CN103105563 A CN 103105563A CN 2013100325206 A CN2013100325206 A CN 2013100325206A CN 201310032520 A CN201310032520 A CN 201310032520A CN 103105563 A CN103105563 A CN 103105563A
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Abstract
The invention discloses an electric power line fault traveling wave network locating method which comprises that when a fault occurs in a line, fault initial traveling wave arrival time is recorded through a fault traveling wave collecting device of each converting station in an electricity transmission network; the fault line is determined according to the initial traveling wave arrival time and a state signal of a relative line breaker; the fault initial traveling wave arrival time is corrected through linear relation of the initial traveling wave arrival time and traveling wave transmission distance according to linear regression analysis of the initial traveling wave arrival time and the traveling wave transmission distance through a least square method; and correcting time serves as a standard, directly proportional relation is formed between difference between the initial traveling wave arrival time of each converting station and traveling wave shortest transmission distance, the linear regression analysis is conducted to the difference and the traveling wave shortest transmission distance according to the least square method, and arrival time of each traveling wave is processed in a mixed mode so that a fault point can be located accurately. The electric power line fault traveling wave network locating method can locate a fault accurately and rapidly and has the advantages of being high in reliability and good in economic performance.
Description
Technical field
The present invention relates to a kind of feeder line fault localization method, particularly a kind of feeder line fault ripple network localization method.
Background technology
Along with the all-round construction of intelligent grid, the safety and reliability that operation of power networks is controlled requires more and more higher, and the accurate location of transmission line malfunction is the difficult problem be left to be desired always.The capable ripple of traditional both-end location is based on a circuit and carries out, only need to catch the initial wave head that arrives circuit two ends row ripple, be not subject to the impact of various reflection waves and refraction wave, principle is relatively simple, but when locating device breaks down or wavefront due in record while error occurring, reliability of positioning can not be guaranteed, and can't meet the requirement of operation of power networks.Although the travelling wave positioning method based on whole electrical network can address the above problem, utilizing the GPS synchronous clock to carry out localization of fault, in severe situation, stochastic error can reach 1us, will cause the range error of 150m left and right.Therefore the recording clock error can cause positioning error large, even locates unsuccessfully; The based on network localization method such as patent 200710035479.2 " electric network functional failure travelling wave positioning method " is only to take average weighted method when information data is processed in addition, the split-second precision of likely ignoring distant place information point, the effect of eliminating the recording clock error is limited, is difficult to realize that fault accurately locates.
Summary of the invention
For solving the technical matters existed in above-mentioned transmission line malfunction location, the invention provides that a kind of precision is high, the feeder line fault ripple network localization method of good economy performance.The present invention utilizes short transmission distance and transmission time relation in direct ratio, on rectangular coordinate plane, wavefront time of arrival and the transmission range of each transformer station's record in electrical network are carried out to fitting a straight line, realize each transformer station's row ripple use processing of time of arrival according to principle of least square method by linear regression analysis, can directly obtain the accurate location of trouble spot.
The technical scheme that the present invention solves the problems of the technologies described above comprises the following steps:
(1) record the initial time that each transformer station's fault traveling wave arrives;
(2) initial time that the fault traveling wave recorded according to each substation arrives and the status information of isolating switch are carried out the failure judgement circuit, and the transformer station arrived the earliest with fault traveling wave is connected and the circuit of circuit breaker trip is faulty line;
(3) the two ends transformer station that is connected with faulty line of definition is respectively the first reference edge and the second reference edge, and the initial row ripple recorded with reference to distolateral each transformer station with faulty line first forms time array t time of arrival
i=(t
1, t
2..., t
n), n is first with reference to the number of distolateral transformer station, with each transformer station divide be clipped to the first reference edge short transmission apart from formation apart from array l
i=(l
1, l
2..., l
n), by the time array with carry out linear fit apart from array, obtain the modified value T of first reference edge initial row ripple time of arrival;
(4) calculate successively faulty line second with reference to the initial row ripple time of arrival of distolateral each transformer station's record and the difference △ t of modified value T, utilize time difference △ t to form time difference array △ t
i=(△ t
1, △ t
2..., △ t
m), m is second with reference to the number of distolateral transformer station, with each transformer station divide be clipped to the first reference edge short transmission apart from formation apart from array
=(
,
...,
), by time difference array with carry out linear fit apart from array, show that trouble spot arrives the accurate distance d of faulty line the first reference edge, realize localization of fault.。
In above-mentioned transmission line malfunction network locating method, in described step (3) by the time array with carry out linear fit apart from array, the modified value T step of calculating for first reference edge initial row ripple time of arrival is: set up coordinate system, wherein abscissa axis represents initial row ripple time of arrival, the axis of ordinates short transmission distance to the first reference edge that is faulty line first with reference to each distolateral transformer station, obviously ordinate faulty line first is accurately with reference to each distolateral transformer station to the short transmission distance of the first reference edge, horizontal ordinate initial row ripple has recording error time of arrival, according to Least Square Regression Analysis, the regretional analysis direction is the horizontal ordinate direction, set up t
i, l
iequation of linear regression l
i=vt
i-Tv, wherein v is row velocity of wave propagation (speed of overhead transmission line approaches the light velocity), the modified value of first reference edge initial row ripple time of arrival of faulty line is:
In above-mentioned transmission line malfunction network locating method, in described step (4), the calculating trouble spot to the accurate distance d step of faulty line the first reference edge is: set up coordinate system, wherein abscissa axis represents the difference of the modified value T of the second initial row ripple time of arrival with reference to distolateral each transformer station record and first reference edge initial row ripple time of arrival, axis of ordinates is second with reference to distolateral each transformer station, to divide the short transmission that is clipped to the first reference edge apart from forming apart from array, obviously to divide with reference to distolateral each transformer station the short transmission distance that is clipped to the first reference edge be accurately to ordinate second, horizontal ordinate second has recording error with reference to the difference of the modified value T of initial row ripple time of arrival of distolateral each transformer station's record and first reference edge initial row ripple time of arrival, according to Least Square Regression Analysis, the regretional analysis direction is the horizontal ordinate direction, set up Δ t
i,
equation of linear regression
=v Δ t
i+ 2d.Trouble spot to the accurate distance of faulty line the first reference edge is:
Technique effect of the present invention is: (1) the present invention utilizes transmission range and transmission time relation in direct ratio, carries out linear fit, has eliminated in conventional both-end fault location algorithm due to the impact of row ripple recording error time of arrival on positioning result; (2) by all record data described point in coordinate system, do not need to judge one by one that whether each data of monitoring point is accurate, during linear fit, can automatically remove the misregistration time, having broken away from the data of weight in the past in data fusion processes, data fusion is more reasonable, has avoided in the weight weighting to representative data unbalanced.
Below in conjunction with drawings and Examples, the present invention is further illustrated.
The accompanying drawing explanation
Fig. 1 is the structural drawing of electrical network in the present invention.
Fig. 2 is process flow diagram of the present invention.
Fig. 3 is the E of transformer station time correction figure in the present invention.
Fig. 4 is the E of transformer station fault fitting a straight line figure in the present invention.
Embodiment
Referring to Fig. 1, Fig. 1 implements configuration of power network of the present invention, whole electrical network has 12 transformer stations, in each transformer station, row ripple locating device is installed, after 38.970km place, DE line middle distance E station breaks down, can be created in the travelling wave signal of propagating in whole power transmission network, at this moment in electrical network, each row ripple locating device all can detect travelling wave signal and record initial row ripple due in as table 1.
Table 1
Fig. 2 is localization of fault process flow diagram of the present invention.The process that positioning master station is carried out localization of fault is as follows:
Positioning master station failure judgement circuit: positioning master station is according to initial row ripple due in and the circuit-breaker status failure judgement circuit of each transformer station's record, be connected with initial row ripple due in transformer station the earliest and the circuit of circuit breaker trip is faulty line, determine that faulty line is DE.
Selecting the E of transformer station is that the first reference edge, the D of transformer station are the second reference edge, with the first reference edge E side transformer station (E, F ..., L) the initial row ripple of record forms time array t time of arrival
i=(t
e, t
f..., t
l), with the first reference edge E side transformer station (E, F ..., L) to the short transmission of the capable ripple of the first reference edge E apart from forming apart from array l
i=(l
e, l
f..., l
l), the first reference edge E is as shown in table 2 to the short transmission distance of initial row ripple time of arrival of each check point of this side E and row ripple.
Table 2
With t
,l
ibe respectively abscissa axis and axis of ordinates, according to Least Square Regression Analysis, the regretional analysis direction is the horizontal ordinate direction, sets up t
i, l
iequation of linear regression l
i=vt
i-Tv.
?
Can effectively reduce like this and disturb the recording error caused.Fig. 3 revises straight line l the time of the first E of reference edge transformer station after linear regression analysis
i=vt
i-Tv.
The difference DELTA t of the initial row ripple time of arrival of calculating successively the second reference edge D side transformer station (D, C, B, A) record and the modified value T of first reference edge E initial row ripple time of arrival, utilize time difference formation time difference array △ t
i=(△ t
d, △ t
b, △ t
c, △ t
a) as shown in table 3, with the second reference edge D side transformer station (D, C, B, A) to the short transmission of the first reference edge D apart from forming apart from array
=(
,
,
) as shown in table 3.
Table 3
With Δ t
i,
be respectively abscissa axis and axis of ordinates, according to Least Square Regression Analysis, the regretional analysis direction is the horizontal ordinate direction, sets up Δ t
i,
equation of linear regression
=v Δ t
i+ 2d.
Trouble spot to the accurate distance of faulty line the first reference edge is:
The accurate distance straight line that after linear regression analysis, faulty line the first reference edge E is arrived in trouble spot as shown in Figure 4
=v Δ t
i+ 2d.
Obviously can show that by Fig. 3 the F of transformer station is for recording initial row ripple inaccurate some time of arrival, disallowable during curve, mistiming and line route have been avoided utilizing in the past, determine the writing time of step whether accurately, utilize curve distribution by the multiple information data fusion simultaneously, reduce and to utilize the how step of data of weight in the past.
The present invention can ask for the short transmission distance of fault traveling wave accurately and rapidly, eliminates the impact of location clocking error on localization of fault fully, the accurate location of realizing fault based on linear equation; Realize simply, be convenient to promote, have broad application prospects.
Claims (3)
1. a feeder line fault ripple network localization method, comprise the steps:
(1) record the initial time that each transformer station's fault traveling wave arrives;
(2) initial time that the fault traveling wave recorded according to each substation arrives and the status information of isolating switch are carried out the failure judgement circuit, and the transformer station arrived the earliest with fault traveling wave is connected and the circuit of circuit breaker trip is faulty line;
(3) the two ends transformer station that is connected with faulty line of definition is respectively the first reference edge and the second reference edge, and the initial row ripple recorded with reference to distolateral each transformer station with faulty line first forms time array t time of arrival
i=(t
1, t
2..., t
n), n is first with reference to the number of distolateral transformer station, with each transformer station divide be clipped to the first reference edge short transmission apart from formation apart from array l
i=(l
1, l
2..., l
n), by the time array with carry out linear fit apart from array, obtain the modified value T of first reference edge initial row ripple time of arrival;
(4) calculate successively faulty line second with reference to the initial row ripple time of arrival of distolateral each transformer station's record and the difference △ t of modified value T, utilize time difference △ t to form time difference array Δ t
i=(△ t
1, △ t
2..., △ t
m), m is second with reference to the number of distolateral transformer station, with each transformer station divide be clipped to the first reference edge short transmission apart from formation apart from array
=(
,
...,
), by time difference array with carry out linear fit apart from array, show that trouble spot arrives the accurate distance d of faulty line the first reference edge, realize localization of fault.
2. transmission line malfunction network locating method according to claim 1, in described step (3) by the time array with carry out linear fit apart from array, the modified value T step of calculating for first reference edge initial row ripple time of arrival is: set up coordinate system, wherein abscissa axis represents initial row ripple t time of arrival
i, axis of ordinates is faulty line first with reference to each distolateral transformer station to the short transmission of the first reference edge apart from l
i, set up t
i, l
iequation of linear regression l
i=vt
i-Tv, wherein v is row velocity of wave propagation (speed of overhead transmission line approaches the light velocity), the modified value of first reference edge initial row ripple time of arrival of faulty line is:
3. transmission line malfunction network locating method according to claim 1, calculating trouble spot in described step (4) to the accurate distance d step of faulty line the first reference edge is: set up coordinate system, wherein abscissa axis represents the difference DELTA t of the modified value T of the second initial row ripple time of arrival of recording with reference to distolateral each transformer station and first reference edge initial row ripple time of arrival
i, axis of ordinates is second with reference to distolateral each transformer station, to divide the capable ripple that is clipped to the first reference edge short transmission distance
, set up Δ t
i,
equation of linear regression
=v Δ titi+2d, trouble spot to the accurate distance of faulty line the first reference edge is:
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