JP5110946B2 - FAILURE LOCATION DEVICE, FAILURE LOCATION METHOD, AND FAILURE LOCATION PROGRAM - Google Patents

Description

  The present invention relates to a failure point locating device, a failure point locating method, and a failure locating method for locating a failure point based on measured values of instantaneous voltage drop measured at a plurality of observation points when a failure occurs in a transmission line constituting the power system. More particularly, the present invention relates to a failure point locating device, a failure point locating method, and a failure point locating program capable of locating a failure point with high accuracy.

  When a failure occurs in a transmission line that constitutes an electric power system, an electric power company needs to quickly identify the location and range where the failure has occurred and make an effort to quickly recover from the failure. In addition, it is necessary to analyze the failure situation and its effects and provide transparent information to customers.

  For this reason, a fault locator (hereinafter referred to as “FL”) is installed in the transmission line as a device for early identification of the failure point. The FL is a device that standardizes a distance from a substation to a failure point as a “distance” when a failure occurs in a transmission line. The FL includes a surge receiving type, a pulse radar type, and the like, but generally an impedance calculation type is used. The impedance calculation type obtains the impedance from the voltage / current at the time of the failure to the failure point in the device installed at one terminal of the transmission line, and determines the failure point.

  However, FL is often installed on high-voltage, long-distance transmission lines such as the main system from the viewpoint of system importance and investment cost control, and is installed on all transmission lines including subordinate systems. There is nothing. For transmission lines that do not have an FL installed, the failure point range is predicted from the lightning location information system and the transmission line route map, etc., but in the case of transmission lines that require extensive inspections or are difficult to reach the site. It takes a lot of time and effort to identify the failure point. In addition, maintenance cost reduction and aging of existing FL are also progressing, and a new failure location method that can be easily applied is required.

  Therefore, focusing on the instantaneous voltage drop (instantaneous voltage drop) phenomenon that occurs at the time of power line failure, a fault location method has been developed that uses the instantaneous low voltage value measured at each observation point during a voltage drop. (See, for example, Non-Patent Documents 1 and 2). In this fault location method, the instantaneous voltage at each observation point is calculated for each fault location, and the difference between the calculated instantaneous voltage value and the instantaneous voltage value measured when the fault occurs is evaluated. Perform orientation.

Yoshimura, Mori, Furukawa, Kihara “Development of fault location method based on measured instantaneous drop and calculated fault value (Part 1)”, 2006 IEEJ Power and Energy Division Conference, No. 415, September 2006 Suetsuji, Tsutsumi, Yoshimura, Ide, Kihara “Development of fault location method based on measured instantaneous drop and calculated fault value (Part 2)”, 2006 IEEJ Power and Energy Division Conference, No. 416, September 2006

However, the conventional fault location method evaluates the sum of squares of the difference between the calculated instantaneous low voltage value and the instantaneous low voltage value measured at the time of failure, and determines the fault point. There was a problem that it could not be standardized. For example, assuming two observation points, the squares of the difference between the calculated values V _c1 and V _c2 and the measured values V _m1 and V _m2 for the correct failure point X are (V _c1 −V _m1 ) ² = a and (V _c2 − If V _m2 ) ² = b, the sum of squares is also the same a + b for another failure point Y such that (V _c1 −V _m1 ) ² = b and (V _c2 −V _m2 ) ² = a , It cannot be specified whether the failure point is X or Y.

  The present invention has been made to solve the above-described problems caused by the prior art, and provides a failure point locating device, a failure point locating method, and a failure point locating program capable of locating a failure point with high accuracy. For the purpose.

In order to solve the above-described problems and achieve the object, the invention according to claim 1 is based on measured values of instantaneous voltage drop measured at a plurality of observation points when a failure occurs in a transmission line constituting the power system. A failure point locating device for locating a failure point, a calculated value calculating means for calculating a calculated value of instantaneous voltage drop at each observation point for each of a plurality of failure positions, and calculated by the calculated value calculating means calculated for each fault location the sum of the average value of the absolute value of the difference between the measured and calculated values of the standard deviation and each observation point of the difference between the measured and calculated values at each observation point as an evaluation value Evaluation value calculating means and failure point specifying means for specifying, as a failure point , a failure position at which the evaluation value calculated for each failure position by the evaluation value calculating means is minimum .

According to the invention of claim 1, and the standard deviation of the difference between the calculated and measured at each observation point of calculating the calculated value of the instantaneous low voltage at each observation point for each plurality of fault location, calculated The sum of the absolute value of the difference between the calculated value and the measured value at each observation point is calculated as an evaluation value for each failure location, and the failure location where the evaluation value calculated for each failure location is minimized is calculated. Since it is configured to be specified as a failure point, it is possible to specify a failure position where the distribution aspect of the calculated value of the instantaneous voltage drop and the measured value coincide with each other as the failure point.

  Further, the invention according to claim 2 further comprises an error large observation point specifying means for evaluating an error of the actual measurement value at each observation point and specifying an observation point where the actual measurement value having a large error is observed. And the evaluation value calculating means calculates an evaluation value by excluding an actual measurement value at the observation location specified by the large error observation location specifying means.

  According to the invention of claim 2, the error of the actual measurement value at each observation point is evaluated, the observation point where the actual measurement value with a large error is observed is specified, and the measurement value at the specified observation point is excluded and evaluated. Since the configuration is such that the value is calculated, it is possible to reduce the influence of the measurement error at the observation location.

  The invention according to claim 3 is characterized in that, in the above-mentioned invention, the calculated value calculating means calculates a calculated value by simulating a low-order small generator as a voltage source.

  According to the third aspect of the present invention, since the calculated value is calculated by simulating the low-order small generator as a voltage source, the calculated value can be calculated more accurately.

  The invention according to claim 4 is characterized in that, in the above invention, when a failure occurs in the upper system, the observation points of the upper system are included in the plurality of observation points.

  According to the fourth aspect of the present invention, when a failure occurs in the upper system, the observation points of the upper system are included in the plurality of observation points. Can be grasped more accurately.

  Further, the invention according to claim 5 is characterized in that, in the above invention, when a failure occurs in the upper system, the plurality of observation points are only the observation points of the upper system.

  According to the invention of claim 5, when a failure occurs in the upper system, the plurality of observation points are configured to be only the observation points of the upper system. It is possible to grasp the aspect more accurately.

  The invention according to claim 6 further comprises failure point range limiting means for limiting a range of failure points specified by the failure point specifying means in the above invention, wherein the calculated value calculation means includes the failure point range. A calculation value of the instantaneous voltage drop at each observation point is calculated for each of a plurality of failure positions within a range limited by the limiting unit.

  According to the invention of claim 6, the range of the failure point to be specified is limited, and the calculation value of the instantaneous voltage drop at each observation point is calculated for each of the plurality of failure positions within the limited range. The amount of calculation can be reduced.

The invention according to claim 7 is characterized in that, in the above invention, a voltage residual ratio is used as the actual measurement value and the calculation value.

According to the seventh aspect of the present invention, since the voltage residual ratio is used as the actually measured value and the calculated value, the residual voltage can be evaluated regardless of the voltage class.

The invention according to claim 8 is based on a failure point locating device that locates a failure point based on measured values of instantaneous low voltage measured at a plurality of observation points when a failure occurs in a transmission line constituting the power system. A failure point locating method, a calculated value calculation step for calculating a calculated value of instantaneous voltage drop at each observation point for each of a plurality of failure positions, and a calculated value at each observation point calculated by the calculated value calculation step an evaluation value calculation step of calculating for each fault location the sum of the average value of the absolute value of the difference between the measured and calculated values of the standard deviation and each observation point of the difference between the measured value as an evaluation value, And a failure point specifying step of specifying, as a failure point , a failure location where the evaluation value calculated for each failure location in the evaluation value calculating step is minimum .

According to the invention of claim 8, and the standard deviation of the difference between the calculated and measured at each observation point of calculating the calculated value of the instantaneous low voltage at each observation point for each plurality of fault location, calculated The sum of the absolute value of the difference between the calculated value and the measured value at each observation point is calculated as an evaluation value for each failure location, and the failure location where the evaluation value calculated for each failure location is minimized is calculated. Since it is configured to be specified as a failure point, it is possible to specify a failure position where the distribution aspect of the calculated value of the instantaneous voltage drop and the measured value coincide with each other as the failure point.

The invention according to claim 9 is a failure point locating program for locating a failure point based on measured values of instantaneous low voltage measured at a plurality of observation points when a failure occurs in a transmission line constituting the power system. A calculation value calculation procedure for calculating a calculated value of the instantaneous voltage drop at each observation point for each of a plurality of failure positions, a calculation value at each observation point calculated by the calculation value calculation procedure, and the actual measurement value, an evaluation value calculation step of calculating for each fault location the sum of the average value of the absolute value of the difference and the standard deviation between the measured values and calculated values at each observation point of the difference as an evaluation value of the evaluation value calculation procedure In this manner, the computer is caused to execute a failure point specifying procedure for specifying, as a failure point , a failure location having a minimum evaluation value calculated for each failure location.

According to the invention of claim 9, and the standard deviation of the difference between the calculated and measured at each observation point of calculating the calculated value of the instantaneous low voltage at each observation point for each plurality of fault location, calculated The sum of the absolute value of the difference between the calculated value and the measured value at each observation point is calculated as an evaluation value for each failure location, and the failure location where the evaluation value calculated for each failure location is minimized is calculated. Since it is configured to be specified as a failure point, it is possible to specify a failure position where the distribution aspect of the calculated value of the instantaneous voltage drop and the measured value coincide with each other as the failure point.

According to the invention of claim 1, 8 or 9, the failure point where the calculated value of the instantaneous voltage drop matches the distribution aspect of the actual measurement value is specified as the failure point, so that the failure point can be determined with high accuracy. There is an effect.

  According to the invention of claim 2, since the influence of the measurement error at the observation location is reduced, the failure point can be determined with higher accuracy.

  According to the invention of claim 3, since the calculated value is calculated more accurately, the failure point can be located with higher accuracy.

  Further, according to the invention of claim 4 or 5, since the distribution aspect of the calculated value and the actually measured value of the instantaneous voltage drop can be grasped more accurately, there is an effect that the failure point can be determined with higher accuracy.

  Further, according to the invention of claim 6, since the amount of calculation is reduced, there is an effect that the failure point can be efficiently determined.

Further, according to the invention of claim 7 , since the residual voltage is evaluated without depending on the voltage class, there is an effect that it is possible to determine the failure point using the actually measured values at the observation points of various voltage classes. .

  Exemplary embodiments of a fault location device, a fault location method, and a fault location program according to the present invention will be described below in detail with reference to the accompanying drawings.

  First, an overview of the failure location method by the failure location system according to the first embodiment will be described. FIG. 1 is an explanatory diagram for explaining an outline of a fault location method by the fault location apparatus according to the first embodiment. When a failure occurs in a certain power transmission line, an instantaneous drop occurs in the vicinity of the failure and in a lower system. At this time, at each observation location, an actual measured value of the instantaneous voltage can be obtained from an oscillograph, an instantaneous voltage recording device, or the like. On the other hand, it is possible to obtain a calculated value of instantaneous voltage drop at a plurality of points (observation points) with respect to a specific failure transmission line, failure location, and failure aspect.

Therefore, as shown in FIG. 1, the failure point locating device according to the first embodiment has a fault power transmission line and a failure aspect given by a tripped circuit breaker and information from a protection relay. The measured value (V ₁ , V ₂ ,... V _N ) of the instantaneous voltage that is measured at the observation point is compared with the calculated value of the instantaneous voltage that is analytically calculated to identify the failure location.

Specifically, the fault locating apparatus according to the first embodiment provides fault point resistance (arc resistance R _a , tower base resistance R _r ) at various fault positions with a given fault transmission line and fault mode. While estimating, the instantaneous voltage drop is repeatedly calculated, and the position where the measured value and the calculated value are the best is determined as the failure point. In other words, the search is performed by iterative calculation to determine “where the failure occurs and where the measured value distribution is such that the instantaneous voltage drop at each observation point is obtained”, and the failure point is determined.

  Next, the configuration of the failure point location apparatus according to the first embodiment will be described. FIG. 2 is a functional block diagram illustrating the configuration of the fault location apparatus according to the first embodiment. As shown in the figure, this fault location apparatus 100 includes a pre-failure voltage calculation unit 110, a pre-failure voltage storage unit 120, a transmission line fault data reading unit 130, a transmission line fault data storage unit 140, and a voltage. A residual ratio calculated value calculation unit 150 and an evaluation unit 160 are included.

  The pre-failure voltage calculation unit 110 is a processing unit that calculates a pre-failure voltage at each observation location and stores it in the pre-failure voltage storage unit 120. Specifically, the pre-failure voltage calculation unit 110 is based on information such as the reference grid data and the circuit breaker / transmission line jumper on / off status immediately before the failure occurs, the individual output of the generator, and the phase-adjustment equipment input capacity. Then, adjust the generator output etc. so that the voltage at each observation point is within the proper range, and create the tidal current cross section before failure. Then, tidal current calculation is performed based on the created pre-failure tidal current section, and pre-fault voltage at each observation location is calculated. The pre-failure voltage storage unit 120 is a storage unit that stores the pre-failure voltage at each observation location.

  The transmission line fault data reading unit 130 reads the measured value of the instantaneous voltage drop at each observation point, the information on the fault transmission line and the fault mode identified from the tripped circuit breaker and the protection relay, and stores them in the transmission line fault data storage unit 140. A processing unit for storing. The transmission line failure data reading unit 130 reads the voltage residual ratio as an actual measurement value of the instantaneous voltage drop. Here, the voltage residual ratio is defined by instantaneous voltage drop (residual voltage) / reference voltage (rated voltage) as shown in FIG. By using the voltage residual ratio, it is possible to evaluate the residual voltage independent of the voltage class. The transmission line fault data storage unit 140 is a storage unit that stores the measured value of the voltage residual ratio at each observation location, information on the faulty transmission line and the fault mode.

  The voltage residual ratio calculation value calculation unit 150 moves the fault location in the fault transmission line and the fault mode, and the pre-failure voltage storage unit 120 stores the calculation value of the voltage residual ratio at each observation location while estimating the fault point resistance. It is a processing unit that calculates using the pre-failure voltage.

  The evaluation unit 160 compares the calculated value of the voltage residual rate calculated for each failure position by the voltage residual rate calculated value calculation unit 150 with the actually measured value of the voltage residual rate stored in the transmission line fault data storage unit 140. It is a processing unit that estimates the most suitable failure point resistance and identifies the failure location. The evaluation unit 160 identifies the failure location by evaluating the degree of coincidence between the calculated value of the voltage residual ratio and the distribution aspect of the actual measurement value.

  FIG. 4 is an explanatory diagram for explaining an evaluation function used by the evaluation unit 160 to evaluate the degree of coincidence between the calculated value of the voltage residual ratio and the actual measurement value. The evaluation unit 160 uses the value obtained by adding the average value of the absolute values of the difference between the measured value and the calculated value to the standard deviation of the difference between the measured value and the calculated value of the voltage residual ratio at the N observation points. As shown in FIG. 4, according to the standard deviation of the difference between the measured value and the calculated value, the degree of coincidence of the “shape” between the measured value and the calculated value, that is, the shape of the broken line connecting the measured value and the calculated value. The degree of coincidence can be evaluated, and the “interval” between the actual value and the calculated value, that is, the degree of coincidence between the actual value and the calculated value can be evaluated by the average value of the absolute values of the difference between the actual value and the calculated value. .

を計算する。ここで、Ｖ_miは観測箇所ｉにおける電圧残留率の実測値であり、Ｖ_ciは観測箇所ｉにおける電圧残留率の計算値である。 Specifically, the evaluation unit 160 identifies the failure point by the following procedure. First, the difference between the actually measured value and the calculated value at each observation point is taken, and the “average of differences” is calculated. That is,

Calculate Here, V _mi is an actual measurement value of the voltage residual rate at the observation point i, and V _ci is a calculated value of the voltage residual rate at the observation point i.

を計算する。ここで、この標準偏差を小さくすることにより実測値と計算値のばらつきをなくし、実測値と計算値の「形」を近づけることができる。 Then, how far the difference between the actually measured value and the calculated value at each observation point is from the “average of the difference” is calculated, and the standard deviation of the difference between the actually measured value and the calculated value is calculated. That is,

Calculate Here, by reducing the standard deviation, it is possible to eliminate the variation between the actually measured value and the calculated value, and to approximate the “shape” of the actually measured value and the calculated value.

を計算する。 Further, in order to evaluate the “interval” between the actually measured value and the calculated value, an average value of absolute values of the difference between the actually measured value and the calculated value is calculated. That is,

Calculate

From the above, the value of the evaluation function expressed by the following equation is calculated.

  Then, by minimizing this evaluation function, it is possible to bring the measured value of the voltage residual ratio to the “shape” and “interval” of the calculated values close to each other. That is, by performing comparative evaluation between the two using this evaluation function, it is possible to estimate the failure point resistance that best matches the two and identify the failure location.

  Next, the process procedure of the fault location process by the fault location apparatus 100 according to the first embodiment will be described. FIG. 5 is a flowchart illustrating the processing procedure of the fault location process by the fault location apparatus 100 according to the first embodiment. As shown in the figure, in this fault location processing, the pre-failure voltage calculation unit 110 creates a pre-failure power flow section (step S1), and uses the created pre-failure power flow section, the pre-failure voltage at each observation location. Is calculated (step S2).

  Then, the transmission line failure data reading unit 130 reads the measured value of the voltage residual ratio, the information on the failed transmission line and the failure aspect (step S3), and stores them in the transmission line failure data storage unit 140. Then, the voltage residual ratio calculation value calculation unit 150 calculates the calculation value of the voltage residual ratio at each observation location by failure calculation while moving the failure position (step S4), and the evaluation unit 160 evaluates the actual measurement value and the evaluation value of the calculation value. F is calculated (step S5), and the failure point resistance and the failure position corresponding to the calculated value that minimizes the evaluation value F are specified (step S6).

  As described above, the evaluation unit 160 calculates the evaluation value F of the actual measurement value and the calculation value, and specifies the failure point resistance and the failure position corresponding to the calculation value that minimizes the evaluation value F, thereby locating the failure point. be able to.

  Next, the evaluation result of the failure point location apparatus 100 according to the first embodiment will be described. The system used for the evaluation is a real system model having about 100 generators, about 500 transmission lines, and about 450 buses. In preparing the current cross section before the failure, the current flow diagram immediately before the failure is used as much as possible, the circuit breaker and transmission line jumper on / off status, the individual generator output, the known bus voltage, and the phased equipment capacity The total demand was used as input data.

  In addition, since the recording device for observing the voltage residual rate at the time of transmission line failure is mainly installed on 66KV (partially 110KV) bus, the failure cases used for evaluation are mainly low-order transmission lines. It is targeted.

  FIG. 6 is a diagram illustrating failure data used for the evaluation of the failure point locating apparatus 100 according to the first embodiment. As shown in the figure, the failure data represents the voltage class of the transmission line in which failure occurred in 19 cases, the state of the failure, and the number of locations where instantaneous voltage drop was observed. Although the number of observation points varies depending on the scale of the failure, all observed actual values are used in the calculation. In addition, the actual failure position in the above case is obtained by the existing FL or the subsequent patrol, and it is possible to evaluate the orientation result by the failure point locating device 100 according to the first embodiment.

  FIG. 7 is a diagram illustrating a fault location result by the fault location apparatus 100 according to the first embodiment. Here, the calculated value is calculated by dividing the power transmission line into 20 (in increments of 5%), and the difference between the failure point specified by the failure point locating device 100 and the actual failure position is used as an orientation error.

  As shown in FIG. 7, 11 cases out of 19 cases have a positioning error within 2 km from the actual failure position. The orientation error of FL is generally about 1 to 2 km although it depends on the voltage class and the transmission line distance. Therefore, the failure point locating device 100 can be evaluated when locating with high accuracy.

  Note that the system model used for fault location does not include small hydropower generators or extra high power generators that are mainly linked to lower systems. The grid data is also simplified as it is treated as a static load model (constant impedance load) as shown in FIG. However, since an actual generator is composed of internal voltage and reactance as shown in Fig. 8 (b), if a failure occurs in a system in which many of these generators are connected, the effect on the orientation result is ignored. become unable.

  FIG. 9 is a diagram illustrating a result of comparing the voltage residual ratios with and without simulating interconnection of a small generator. Note that the calculation of the voltage residual ratio here is based on the comparison with the presence or absence of interconnection of small generators, so it is calculated using the fault transmission line, fault mode, and fault location obtained as actual fault data. (However, failure point resistance is not considered). From FIG. 9, it can be seen that when the interconnection of the small generator is simulated, the voltage residual ratio at the observation location near the interconnection is maintained at a value close to the actually measured value as compared with the case where the voltage residual rate is not simulated. Further, the failure point locating apparatus 100 compares the measured value and the calculated value of the voltage residual ratio. Therefore, if the calculated value of the voltage residual ratio changes due to the interconnection of small generators as shown in FIG. 9, the orientation result is also affected.

  Therefore, in FIG. 6, 12 cases where interconnection of small generators can be considered were simulated, and fault location was performed. As a result, as shown in FIG. 10, improvement in the orientation accuracy was observed in many cases. This is considered to be due to the fact that the calculated value of the voltage residual ratio was appropriately calculated and brought closer to the actually measured value by considering the small generator. Therefore, it is thought that accurate simulation of system data is indispensable for improving the orientation accuracy, including the interconnection of small generators.

  As described above, in the first embodiment, the evaluation unit 160 adds the absolute value of the difference between the measured value and the calculated value of the voltage residual ratio to the standard deviation of the difference between the measured value and the calculated value of the voltage residual rate at the observation location. Since the evaluation value F including the average value is calculated for each failure position, and the failure position where the evaluation value F is minimized is determined as the failure point, the voltage residual ratio obtained at each observation point is actually measured. It is possible to determine the failure point having the most similar “shape” and “interval” to the value distribution, and it is possible to determine the failure point with high accuracy.

  The actual measurement value obtained from the observation location may include a large error due to a failure of the observation device or an acquisition error. The actual measurement value including such an error cannot be appropriately compared with the calculated value, and thus affects the orientation result. Therefore, in the second embodiment, a failure point locating device that identifies actual measurement values with many errors and prevents the measurement results of the observation points corresponding to the identified actual measurement values from being used for the orientation will be described.

  First, the configuration of the fault location apparatus according to the second embodiment will be described. FIG. 11 is a functional block diagram illustrating the configuration of the fault location apparatus according to the second embodiment. Here, for convenience of explanation, functional units that play the same functions as the respective units shown in FIG. As shown in FIG. 11, the failure point locating device 200 has an evaluation unit 260 instead of the evaluation unit 160 in comparison with the failure point locating device 100 shown in FIG. 2, and a measured value evaluation unit 270 is newly added. Have.

  The actual measurement value evaluation unit 270 evaluates the accuracy of the actual measurement value at each observation location based on the standard deviation of the difference between the actual measurement value and the calculated value of the voltage residual ratio at each observation location, and identifies a measurement value with a large error. The observation part corresponding to the specified actual measurement value is notified to the evaluation unit 260. As the calculated value, a value calculated by using the voltage residual ratio calculated value calculation unit 150 from actual fault data (fault transmission line, fault mode, fault position) obtained by patrol after the occurrence of the fault is used.

  FIG. 12 is a diagram illustrating a specific example of an actually measured value with a large error. In the figure, an observation point where the difference between the measured value and the calculated value of the voltage residual ratio is 2σ (σ is a standard deviation) or more is specified as an observation point with a large error.

  Similar to the evaluation unit 160, the evaluation unit 260 evaluates the degree of coincidence of both based on the calculated value of the voltage residual ratio and the distribution aspect of the actual measurement value, except for the observation point notified from the actual value evaluation unit 270. An evaluation value F is calculated. Thus, by calculating the evaluation value F by removing the actual measurement value having a large error, the failure point can be determined with higher accuracy.

  FIG. 13 is a diagram illustrating a fault location result by the fault location apparatus 200 according to the second embodiment. In the figure, the column “Before selection” shows the case where the evaluation value F is calculated without removing observation points with large errors, and the column “After selection” calculates the evaluation value F excluding observation points with large errors. Shows the case.

  As shown in the figure, improvement in the orientation accuracy is seen in cases [4] and [9]. This is considered to be because the calculated value of the voltage residual ratio can be made closer to the actually measured value by removing the actually measured value having a large error.

  On the other hand, in case [16], no improvement in orientation accuracy was observed. This is thought to be because the excluded observation points were characteristic of this failure (distribution aspect of the voltage residual ratio). Such observation points are a great clue in searching for failure points, so it is necessary to be careful about whether or not they can be excluded, and it is not excluded from a single accuracy evaluation. It is important to judge.

  In addition, since standard deviation is used for evaluation of actual measurement values, a sufficient amount of actual measurement values are required when specifying an excluded portion. When there are few observation points, the actual measurement value may be further reduced by excluding observation points with large errors, and accuracy may not be improved. For this reason, it is necessary not to exclude observation points in the case of a subordinate fault case with relatively few actual measurement values.

  As described above, in the second embodiment, the actual measurement value evaluation unit 270 specifies the actual measurement value and the observation location with a large error, and the evaluation unit 260 calculates the evaluation value F except for the observation location with the large error. Therefore, the failure point can be determined with higher accuracy.

  In the second embodiment, the observation points corresponding to the actually measured values with many errors are specified, and the measurement results at those observation points are not used for the subsequent orientation. By specifying the actual measurement value with a large error while calculating the calculated value, it is possible to determine the failure point while excluding the observation point with the large error.

  Further, in FIG. 7, although a relatively good result of the positioning accuracy was obtained in the failure case of the lower system, a large error has occurred in the failure case of the upper system, particularly case [5]. This is considered to be because the distribution aspect could not be accurately grasped because the 500 kv transmission line failure was standardized using the measured value of the lower bus.

  Therefore, in the case [5], the fault location is newly performed including the actually measured value of the upper system (220 kv, 500 kv) at the time of occurrence of the fault. As a result, as shown in FIG. 14, improvement in the orientation accuracy was observed. This is probably because the number of actually measured values to be evaluated has increased by including the host system actually measured values, making it easier to grasp the distribution aspect.

  FIGS. 15 and 16 show the post-analytical calculation of the calculated voltage residual ratio and compare it with the actual measurement. FIG. 15 shows a case where the higher system actual measurement value is included, and FIG. 16 shows a case where only the upper system actual measurement value is included. Comparing these figures, the measured value and the calculated value are very close in the case of only the higher-order measured value. Therefore, when an accident occurs in the host system, the fault location is determined using only the host system actually measured values, thereby further improving the orientation accuracy as shown in FIG. As described above, it is considered effective to use an actual measurement value in the vicinity of the fault voltage class in order to improve the orientation accuracy.

  FIG. 17 is a diagram collectively showing the failure point location results by the failure point location apparatuses 100 and 200 according to the first and second embodiments. In the figure, the column “Before Improvement Measure” shows the failure point location result by the failure point locating apparatus 100, and the column “Improvement Measure” is a small generator simulation (small generator) and excludes observation points with large errors ( (Selection), use of higher system measured values (upper system) shows the added accuracy improvement measures, and the column “After Improvement Measures” shows the failure point when the accuracy improvement measures shown in the “Enhancement Measures” column are added The orientation results are shown. However, observation points that characterize failures are not excluded. As shown in FIG. 17, the orientation error is within 2 km in 15 cases out of 19 cases, and the orientation result is almost the same as that of the existing FL.

  In the first and second embodiments, the failure point locating device has been described. However, a failure point locating program having the same function can be obtained by realizing the configuration of the failure point locating device with software. Therefore, a computer that executes this fault location program will be described.

  FIG. 18 is a functional block diagram illustrating the configuration of a computer that executes the fault location program according to the first and second embodiments. As shown in the figure, the computer 300 includes a RAM 310, a CPU 320, an HDD 330, a LAN interface 340, an input / output interface 350, and a DVD drive 360.

  The RAM 310 is a memory that stores a program, a program execution result, and the like. The CPU 320 is a central processing unit that reads a program from the RAM 310 and executes the program. The HDD 330 is a disk device that stores programs and data, and the LAN interface 340 is an interface for connecting the computer 300 to other computers via the LAN. The input / output interface 350 is an interface for connecting an input device such as a mouse or a keyboard and a display device, and the DVD drive 360 is a device for reading / writing a DVD.

  The failure location program 311 executed in the computer 300 is stored in the DVD, read from the DVD by the DVD drive 360, and installed in the computer 300. Alternatively, the fault location program 311 is stored in a database or the like of another computer system connected via the LAN interface 340, read from these databases, and installed in the computer 300. The installed fault location program 311 is stored in the HDD 330, read into the RAM 310, and executed by the CPU 320.

  Further, in the first and second embodiments, the case where the failure point locating device inputs information on the failure transmission line and the failure aspect from the outside has been described. However, the present invention is not limited to this, and the failure point locating device. However, the present invention can be similarly applied to the case where the faulty transmission line and the fault appearance are identified from the instantaneous low voltage. That is, when calculating the calculated value of the voltage residual ratio, the fault location is specified while estimating the fault mode and the fault transmission line by adding the fault mode and fault transmission line in addition to the fault point resistance and fault location as unknowns. You can also. However, if the number of unknowns is increased, the amount of calculation increases. Therefore, it is necessary to limit the range of failure points to some extent and specify the failure location in detail within the limited range.

  For example, in the first and second embodiments, when calculating the calculated value of the voltage residual ratio, the transmission line is divided into 20 parts and calculated in order. However, the failure location is screened (limited) with fewer divisions first. By dividing the transmission line more finely within the screened range and calculating the calculated value, the calculated value of the voltage residual ratio can be calculated efficiently.

  As described above, the failure point locating device, the failure point locating method, and the failure point locating program according to the present invention are useful for specifying the failure position of the transmission line constituting the power system, and in particular, the FL is not installed. Suitable when a failure occurs in the transmission line.

It is explanatory drawing for demonstrating the outline | summary of the fault location method by the fault location apparatus which concerns on the present Example 1. FIG. It is a functional block diagram which shows the structure of the failure point location apparatus which concerns on the present Example 1. FIG. It is a figure which shows the definition of a voltage residual ratio. It is explanatory drawing for demonstrating the evaluation function used in order for an evaluation part to evaluate the coincidence of the calculated value of a voltage residual ratio, and an actual value. It is a flowchart which shows the process sequence of the failure point location process by the failure point location apparatus which concerns on the present Example 1. FIG. It is a figure which shows the failure data used for evaluation of the failure point location apparatus which concerns on the present Example 1. FIG. It is a figure which shows the failure point location result by the failure point location apparatus which concerns on the present Example 1. FIG. It is a figure which shows a small generator model. It is a figure which shows the result of having compared the voltage residual rate with the case where it does not simulate the interconnection of a small generator, and the case where it does not. It is a figure which shows the orientation result at the time of simulating a small generator. It is a functional block diagram which shows the structure of the failure point location apparatus which concerns on the present Example 2. It is a figure which shows the specific example of the actual value with a big error. It is a figure which shows the failure point location result by the failure point location apparatus which concerns on the present Example 2. FIG. It is a figure which shows the orientation result at the time of using a higher system actual value. It is a figure which shows the measured value and calculated value of a voltage residual rate at the time of using a higher system measured value. It is a figure which shows the measured value and calculated value of a voltage residual rate at the time of using only a high-order system measured value. It is a figure which shows collectively the failure point location result by the failure point location apparatus which concerns on the present Examples 1 and 2. It is a functional block diagram which shows the structure of the computer which executes the fault location program concerning a present Example.

Explanation of symbols

100, 200 Fault location device 110 Pre-failure voltage calculation unit 120 Pre-failure voltage storage unit 130 Transmission line failure data reading unit 140 Transmission line failure data storage unit 150 Voltage residual ratio calculation value calculation unit 160, 260 Evaluation unit 270 Actual value evaluation Part 300 Computer 310 RAM
311 Fault location program 320 CPU
330 HDD
340 LAN interface 350 I / O interface 360 DVD drive

Claims (9)

A failure point locating device for locating a failure point based on measured values of instantaneous low voltage measured at a plurality of observation points when a failure occurs in a transmission line constituting the power system,
A calculated value calculating means for calculating a calculated value of the instantaneous voltage drop at each observation point for each of a plurality of failure positions;
The calculated value calculation means calculated value and the actual measurement value and the evaluation value of the sum of the average value of the absolute value of the difference and the standard deviation of the difference between the measured and calculated values at each observation point of at each observation point calculated by Evaluation value calculation means for calculating for each failure position as,
A failure point locating device comprising: a failure point specifying unit that specifies, as a failure point , a failure position having a minimum evaluation value calculated for each failure location by the evaluation value calculating unit. An error large observation point specifying means for evaluating an error of the actual measurement value at each observation point and specifying an observation point where the actual measurement value with a large error is observed is further provided,
The failure point locating apparatus according to claim 1, wherein the evaluation value calculating unit calculates an evaluation value by excluding an actual measurement value at an observation point specified by the large error observation point specifying unit.   The failure point locating device according to claim 1, wherein the calculated value calculating means calculates a calculated value by simulating a low-order small generator as a voltage source.   The failure point locating apparatus according to claim 1, 2, or 3, wherein when a failure occurs in the upper system, the observation points of the upper system are included in the plurality of observation points.   The fault location apparatus according to claim 1, 2, or 3, wherein when a fault occurs in the upper system, the plurality of observation points are only the upper system observation points. Further comprising failure point range limiting means for limiting the range of failure points specified by the failure point specifying means;
6. The calculated value calculating means calculates a calculated value of an instantaneous voltage drop at each observation point for each of a plurality of failure positions within a range limited by the failure point range limiting means. The fault location apparatus as described in any one of these. Fault point locating system according to any one of claims 1-6, characterized by using the voltage remaining constant as said measured values and calculated values. A failure point locating method by a failure point locating device for locating a failure point based on measured values of instantaneous low voltage measured at a plurality of observation points when a failure occurs in a transmission line constituting the power system,
A calculated value calculating step for calculating a calculated value of instantaneous voltage drop at each observation point for each of a plurality of failure positions;
The calculated value evaluation value sum of the average value of the absolute value of the difference between the calculated value and the measured value of the standard deviation and each observation point of the difference between the calculated value and the measured value at each observation point calculated by the calculating step An evaluation value calculating step for calculating for each failure position as
A failure point locating method comprising: a failure point specifying step of specifying, as a failure point , a failure position having a minimum evaluation value calculated for each failure location in the evaluation value calculating step. A fault location program that locates a fault point based on measured values of instantaneous voltage drop at a plurality of observation points when a fault occurs in a transmission line constituting the power system,
A calculation value calculation procedure for calculating a calculation value of instantaneous voltage drop at each observation point for each of a plurality of failure positions;
The calculated value calculation procedure calculated value and the actual measurement value and the evaluation value of the sum of the average value of the absolute value of the difference and the standard deviation of the difference between the measured and calculated values at each observation point of at each observation point calculated by As an evaluation value calculation procedure to calculate for each failure position,
A failure point locating program that causes a computer to execute a failure point specifying procedure for specifying, as a failure point , a failure position having a minimum evaluation value calculated for each failure location by the evaluation value calculation procedure.

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