JP4201189B2 - Transmission line fault location system - Google Patents

Description

  The present invention relates to a transmission line failure point locating system, and more particularly to a transmission line failure point locating system for locating a failure point based on a surge generated in a transmission line.

  Conventionally, surges that occur when the transmission line is grounded, short-circuited, or when lightning strikes the transmission line directly are received by the master station and slave stations provided at the transmission end and reception end of the transmission line. There is known a surge locating system for locating an occurrence point.

  FIG. 8 is a principle diagram of a conventional surge localization system. In this fault location system, the surge arrival time is detected at the master station 2 (electricity station A) and the slave station 3 (electricity station B) provided at the end of the transmission line 1, and the difference between the detected surge arrival times is obtained. The distance L1 from the master station 2 to the surge occurrence location is calculated using the following equation (1).

L1 = (L + c · Δt) / 2 (1)
Here, L is the distance between the master station 2 and the slave station 3 installed at both ends of the transmission line, Δt is the difference in surge arrival time between the master station 2 and the slave station 3, and c is the surge propagation speed. is there.

  FIG. 9 is a principle diagram of a surge localization system proposed in Patent Document 1 below, which can cope with a case where the power transmission line 1 has a plurality of branches 1, 2,. The master station 2 or the slave stations 3, 4,... Are arranged at the power transmission end and the power reception end of the power transmission line 1. Each of the master station 2 and the slave stations 3, 4,... Receives a surge generated in the transmission line 1, and receives radio waves from the artificial satellite, and according to a periodic pulse generated based on this. Counter means for operating and generating a counter value indicating a surge arrival time in response to an output from the surge receiving means, and transmitting means for transmitting the counter value generated by the counter means.

  In this surge locating system, if the surge occurrence point that is standardized based on the counter value of the surge arrival time of the master station 2 and the slave station 3 is not near the branch 1, 2,. If the determined surge occurrence point is near the branch point 1, 2,..., It is possible that a surge will occur on the branch side, so the surge value is determined from the counter value of the surge arrival time of the master station 2 and the slave station on the branch side. Determine the point of origin.

  For example, as shown in FIG. 9, if a surge occurs at a point P, the surge occurrence point is determined by the count values of the master station 2 and the slave station 3. If a surge occurs at point Q, the surge occurrence point is calculated from the count values of the master station 2 and the slave station 3. In this case, the calculated surge occurrence point is in the vicinity of branch 1, so that the master station 2 The surge occurrence point is determined by the count value of the slave station 4. Thus, by selecting the two stations to be used for the orientation based on the counter value, it is possible to easily obtain the surge occurrence point even if there is a branch.

  FIG. 10 is a principle diagram of the surge localization system proposed in Patent Document 2 below. This surge locating system also includes the surge time and information from the slave stations 3, 4,... That transmit the surge time and information about the transmission and distribution line 1 to the master station 2, and the slave stations 3, 4,. In addition, a master station 2 that specifies a surge occurrence section is arranged on the transmission and distribution line 1. The slave stations 3, 4,... Receive the GPS radio wave, synchronize the current time held by the GPS and the current time of their own, identify the surge detection time of the transmission and distribution line 1, and the polarity of the surge current And the surge detection time and surge current polarity information are transmitted to the master station 2 through the communication network. The master station 2 is located between the slave station 3 closest to the power supply terminal of the transmission / distribution line 1 and the plurality of terminal slave stations of the transmission / distribution line 1 from the surge detection time transmitted from the slave stations 3, 4,. Then, the surge generation position candidate point of the transmission / distribution line 1 is identified from the difference in the surge detection time and the length of the transmission / distribution line 1 between the slave stations, and the transmission / distribution line 1 within a predetermined range including the candidate point is synthesized. The surge occurrence position candidate section. Furthermore, the surge current polarity information of the slave station included in the surge occurrence position candidate section and the surge current of the slave station adjacent to the slave station not included in the surge occurrence position candidate section but included in the surge occurrence position candidate section From the polarity information, a section without branching is identified as a surge generation section, and is defined as a surge generation section.

  For example, as shown in FIG. 10, if a surge occurs at point R, the surge occurrence position candidate section is obtained from the surge detection times of the slave station 3 at the power supply terminal and the terminal slave stations 6 and 8, and the obtained surge occurrence position The surge current polarities of the slave stations 3, 5, and 7 adjacent to the slave station 4 in the candidate section are compared, and the surge occurrence section is limited to between the slave stations 3 and 4.

In this way, the surge occurrence position candidate section is obtained at the surge arrival time of both terminal stations of the transmission and distribution lines, and the surge occurrence section is obtained based on the surge current polarity of the slave station in the vicinity of the obtained surge occurrence position candidate section. Even if there is a branch in the distribution line and the number of slave stations installed on it is large, it is possible to limit the surge occurrence section with a relatively simple procedure.
JP-A-8-184635 JP 2000-193707 A

  A general power transmission line has a long line length and a branch in the middle. A high-frequency component such as a lightning surge is demultiplexed by a branch and its level is lowered. Therefore, in order to detect a surge at both ends of a transmission line, it is necessary to lower a surge detection threshold. However, when the threshold for surge detection is lowered, the problem arises that the surge localization system frequently operates with induced lightning. Further, since the surge propagation distance becomes longer when the line length of the transmission line is longer, in order to calculate the surge occurrence point with high accuracy, it is necessary to consider influences such as variations in surge propagation speed and sagging of the electric wire.

  In the case of FIG. 9, since two stations used for surge generation point location are selected according to the surge arrival times of the master station 2 and the main line terminal station 3, the surge occurrence point standardized on the main line is detected when a surge occurs at a branch. If the error is large and it is not included within the branching range, it is misdirected.

  In FIG. 10, a plurality of slave stations 3, 4,... Are installed in the middle of the transmission / distribution line 1, and the surge generation section is determined by the surge current polarity information of each slave station. In order to make the distance about 300 m, it is necessary to install slave stations on all the steel towers with an average distance of 300 m between the steel towers. This is not realistic for locating a surge occurrence point on a transmission line.

  Moreover, as shown in FIG. 11A, when the slave stations 4 and 5 are installed on the power transmission line 1 at a distance of 18 km, for example, the lightning surge waveform of the slave stations 4 and 5 is shown in FIG. In addition, lightning surge has many high-frequency components, and when the slave station is separated, the surge waveform shape may change due to the influence of the reflected wave or waveform distortion at the branch point, making it difficult to determine the surge current polarity.

  An object of the present invention is to provide a power transmission line fault location system that can determine a fault point relatively easily and accurately even when a long line such as a power transmission line has a branch.

In order to solve the above-described problem, the present invention provides a plurality of slave stations that are arranged on a power transmission line and that transmit information related to the power transmission line to a master station, and a master that identifies a failure point based on information from the slave station In the transmission line fault location system having a station, the slave station receives GPS radio waves from an artificial satellite and detects a current that the GPS has, and a fault current flowing in the transmission line. Fault current detection means for outputting fault current information, fault voltage detection means for detecting fault voltage generated in the transmission line and outputting fault voltage information, fault current immediately after a surge occurs in the transmission line Current voltage monitoring means for sending out a failure state flag corresponding to the change state and the change state of the failure voltage, and the surge detection time is extracted from the GPS reception means, and the surge detection time and surge peak value are determined from the failure state. Surge detection means for sending together with a lag, and failure information transmission means for sending the surge detection time, the surge peak value, the failure state flag, the failure current information and the failure voltage information as failure information to the master station through a communication network The master station, fault information receiving means for receiving fault information from the fault information transmitting means, slave station selection processing means for selecting a slave station to be used for orientation based on the fault information, Surge occurrence point calculation processing means for calculating the surge occurrence point using the surge detection time of the slave station selected by the slave station selection processing means, and the failure of the slave station used for calculating the surge occurrence point by the surge occurrence point calculation processing means and a fault point display selection processing means for selecting a fault point display according to the state flag, the slave station selection processing means, chromatic fault detection by the state of the fault condition flag In the case of failure detection, two or more slave stations are selected from the slave stations with different surge current current values and phase angles that have earlier surge detection times. If no failure is detected, The two or more slave stations are selected from those with the earlier surge detection time, and the surge occurrence point calculation processing means is selected when there are three or more slave stations selected by the slave station selection processing means. Select three of the slave stations with the earliest surge detection time, calculate the surge occurrence point for all three combinations, and calculate the average of the two surge occurrence points that are close to the calculated surge occurrence point. Alternatively , the first characteristic is that a surge occurrence point having a smaller difference in surge detection time among two surge occurrence points close to the calculated surge occurrence point is used.

  The second feature of the present invention is that, in the slave station, the failure information transmitted by the failure information transmitting means can be selected according to the failure state flag.

  Further, according to the present invention, the slave station selection processing unit divides the slave stations into groups according to the fault current information and the fault voltage information, and arranges the slave stations in order of surge detection time for each group, and the surge detection time is earliest in each group The third feature is to select a slave station.

Furthermore, the present invention is the master station, based on a combination of the surge peak value and the fault state flag, to locating a ground wire lightning point that does not malfunction to be the fourth feature.

  According to the first feature, a slave station to be used for orientation among a plurality of slave stations arranged at appropriate intervals on the transmission line is determined based on failure information such as surge detection time, failure current information, and failure voltage information. Since it is selected and standardized based on the surge detection time for these slave stations, there is no need to consider the effects of fluctuations in surge propagation speed and wire sagging even in complicated and long transmission line systems, and surges can be generated accurately. The location can be standardized.

  Here, instead of selecting a slave station to be used for standardization based only on the surge detection time, a slave station to be used for standardization is selected based on fault current information and fault voltage information in addition to the surge detection time. Even if it is a slave station arranged in the middle of the electric wire, two stations sandwiching the surge occurrence point can be reliably selected.

Further, since the failure point display can be selected using the failure state flag, for example, the failure point due to the surge and the surge point of the induced lightning surge can be distinguished and displayed. As a result, in the event of a failure, the transmission line is inspected immediately, and in the case of an induced lightning surge, the occurrence status history is accumulated, and the transmission line at the location where the surge occurs frequently is checked as a result. The preventive maintenance of electric wires can be performed efficiently. Further, when there is a branch, the surge occurrence point can be determined without placing a slave station at the branch point.

  According to the second feature, frequent operation by induced lightning can be suppressed when the surge detection threshold is lowered.

  According to the third feature, even if the slave station is arranged in the middle of an ultra-high-voltage transmission line in which a fault current flows from both ends or a transmission line having a large charging current, two slave stations sandwiching the surge occurrence point Can be selected accurately and reliably.

According to the fourth feature, the preventive maintenance of the fictitious value line can be effectively performed.

  The present invention will be described below with reference to the drawings. The present invention includes a plurality of slave stations arranged at appropriate intervals in the main line or branch line of the power transmission line and in the middle of the line, and at least one master station.

  FIG. 1 is a block diagram showing a configuration example of a slave station of a transmission line fault location system according to the present invention. As shown in the figure, the slave station includes GPS receiving means 11, fault current detecting means 12, fault voltage detecting means 13, current voltage monitoring means 14, surge detecting means 15, and fault information transmitting means 16.

  The GPS receiving means 11 includes a GPS antenna 111 and a GPS receiver 112 that receive GPS signals from artificial satellites (not shown). The GPS receiver 112 receives the encoded information transmitted from the artificial satellite, and generates a reset signal and a current time every second synchronized with the encoded information. In addition, the GPS receiver 112 sends a reset signal to the control CPU 161 of the failure information transmission means 16 and receives a time in nsec units less than 1 second counted by the control CPU 161 based on the reset signal. Further, when receiving the surge detection signal from the surge detection means 15, the GPS receiver 112 sends the time at that time to the surge detection means 15 as a time of less than 1 msec display.

  The fault current detection means 12 includes a current sensor 121 that detects a current flowing through the transmission line, a filter 122 that extracts a commercial frequency component from the current waveform detected by the current sensor 121, and an A / D that converts the output signal of the filter 122 into a digital signal. A converter 123 and a fault current detector 124 are included.

  The fault current detection unit 124 takes out the change in the current waveform converted into a digital signal, compares it with a preset failure certification level, and generates a fault based on the fault current when the current change exceeds the fault certification level. A signal is sent to the current voltage monitoring means 14. The fault current detection unit 124 stores fault current information such as a fault current waveform, current value, and phase angle, and sends the fault current information to the fault information transmitting means 16.

  The failure voltage detection means 13 includes a voltage sensor 131 that detects a voltage generated in the transmission line, a filter 132 that extracts a commercial frequency component from the voltage waveform detected by the voltage sensor 131, and an output signal A / A that converts the output signal of the filter 132 into a digital signal. A D converter 133 and a fault voltage detector 134 are included.

  The failure voltage detection unit 134 extracts a change in the voltage waveform converted into a digital signal, compares it with a preset failure certification level, and based on the failure voltage when the change in the voltage waveform exceeds the failure certification level. A failure occurrence signal is sent to the current voltage monitoring means 14. The failure voltage detection unit 134 stores failure voltage information such as a failure voltage waveform, a voltage value, and a phase angle, and sends the phase angle to the failure information transmission unit 16.

  Each slave station can include a plurality of fault current detection means 12 and fault voltage detection means 13. It is also possible to provide a plurality of failure qualification levels in the failure current detection means 12 and the failure voltage detection means 13 so as to be transmitted to the current voltage monitoring means 14 finely to the extent of the failure state.

  When a failure occurrence signal is sent from at least one of the failure current detection unit 12 and the failure voltage detection unit 13, the current / voltage monitoring unit 14 changes the failure state flag and transmits the failure state flag to the surge detection unit 15. For example, if the normal failure state flag is set to “0”, when a failure occurrence signal is received, the failure state flag is set to “1” and a failure state flag of “1” is sent to the surge detection means 15. When a plurality of failure certification levels are provided in the failure current detection means 12 and the failure voltage detection means 13, a plurality of failure status flags are set correspondingly.

  The surge detection means 15 is a surge sensor 151 that detects a lightning surge or an electrical failure surge that has occurred in the transmission line, a filter 152 that converts a surge waveform detected by the surge sensor 151 into a voltage that can be processed by an electronic circuit, and extracts a high-frequency component, An A / D converter 153 that converts the output signal of the filter 152 into a digital signal and a surge detector 154 are included.

The surge detection unit 154 compares the voltage output from the A / D converter 153 with a threshold value V _TH greater than the noise level, and when the voltage output from the A / D converter 153 is greater than the threshold value V _TH The surge detection signal is sent to the GPS receiving means 11. Then, the time when the surge detection signal is generated (surge detection time) is received from the GPS receiving means 11 and stored together with the surge peak value and the failure state flag sent from the current voltage monitoring means 14, and these are transmitted as failure information. Send to means 16. Note that the surge and the threshold value V _TH may be compared at the analog signal stage before A / D conversion.

  The failure information transmission means 16 includes a surge detection time sent from the surge detection means 15, a surge peak value and a failure state flag, a current value and phase of the failure current sent from the failure current detection means 2, and a failure voltage detection means. 3, a control CPU 161 for transmission control of failure information such as the voltage value and phase of the failure voltage sent from 3, a memory 162 for temporarily storing data such as failure information, and the failure information in the overhead ground wire (OPGW) The optical modem 163 for transmitting to the master station through the optical fiber 17 is provided.

  A surge waveform, a fault current waveform, and a fault voltage waveform may be transmitted to the master station as fault information. In addition, by changing the optical modem 163 to a mobile phone, a wireless modem, a satellite communication radio, or the like, failure information can be transmitted to the master station using each communication network.

Next, an outline of surge detection processing in the slave station having the above-described configuration will be described with reference to FIG. FIG. 2 is a waveform diagram when an electrical failure occurs after the occurrence of a lightning surge. When the surge exceeds a threshold value V _TH (surge detection level), the slave station surge detection means 15 sends a surge detection signal to the GPU reception means 11 and receives the time (surge detection time) at that time. Store the peak value.

  The fault current detection means 12 takes out a change in the current flowing through the transmission line and monitors it as a fault current waveform. When the failure current waveform exceeds the failure recognition level, the failure current detection means 12 sends a failure occurrence signal to the current voltage monitoring means 14 as a failure has occurred. Further, the fault current waveform, current value, and phase angle are stored.

  The failure voltage detection means 13 takes out a change in voltage generated in the transmission line and monitors it as a failure voltage waveform. When the failure voltage waveform exceeds the failure recognition level, the failure voltage detection unit 13 sends a failure occurrence signal to the current voltage monitoring unit 4 as a failure has occurred. Also, the fault voltage waveform, current value, and phase angle are stored.

  When receiving a failure occurrence signal from at least one of the failure current detection unit 12 and the failure voltage detection unit 13, the current voltage monitoring unit 14 sets the failure state flag to “1” and sends it to the surge detection unit 15.

  The surge detection means 15 adds a failure state flag to the surge detection time and surge peak value and sends it to the failure information transmission means 16 and stores the surge waveform.

  The failure information transmission means 16 detects the surge detection time, surge peak value and failure state flag sent from the surge detection means 15, current value and phase angle of the failure current sent from the failure current detection means 12, and failure voltage detection. The voltage value and phase angle of the fault voltage sent from the means 13 are sent to the master station as fault information.

  FIG. 3 is a block diagram showing a configuration example of the master station of the transmission line fault location system according to the present invention. As shown in the figure, the master station includes a failure information receiving means 31, a slave station selection processing means 32, a surge occurrence point calculation processing means 33, a failure point display selection processing means 34, a transmission line database 35, and a monitor 36. The failure information receiving means 31 includes an optical modem 311 and a data formation processing unit 312.

  In the power transmission line database 35, information on installed power transmission lines and slave stations is stored in advance. This information includes, for example, the slave station number, the length of the transmission line between the slave stations, the branch tower number, the length of the transmission line between the branch tower and the adjacent slave station.

  The master station is incorporated in a personal computer, and the slave station selection processing means 32, surge generation point calculation processing means 33, and failure point display selection processing means 34 can be configured as hardware or software. Are configured to be called and executed by the central processing unit.

  Next, an outline of processing in the master station having the above configuration will be described. The failure information receiving means 31 receives failure information sent from each slave station.

  The failure information receiving means 31 receives failure information sent from each slave station via the optical fiber 17 in the overhead ground wire, converts it, and sends it to the slave station selection processing means 32. The slave station selection processing means 32 selects a slave station to be used by the surge occurrence point calculation processing means 33 based on the failure information.

  When two slave stations are selected by the slave station selection processing means 32, the surge generation point calculation processing means 33 uses the surge detection time of the selected slave station to calculate the surge occurrence point by the above equation (1). . When three or more slave stations are selected by the slave station selection processing means 32, a surge occurrence point is calculated by a method described later.

  The failure point display selection processing means 34 checks the failure state flags of all the slave stations, and if the failure state flag is “1” even at one station, the calculated surge occurrence point is displayed on the monitor 36 as a failure point. Let At this time, if the failure status flag is not “1”, a surge point is displayed as a surge caused by an induced lightning without electrical failure, and the failure surge and other surges such as induced lightning are distinguished and displayed. .

  Furthermore, statistical processing is performed by taking a history of the point of occurrence of the surge and the time of occurrence of the surge, and in the case of a surge that does not require an emergency other than a failure surge, a frequently occurring vicinity can be inspected at a later date.

  Hereinafter, the operation of the fault location system composed of the slave station and the master station having the above configuration will be described with a specific example. FIG. 4 shows an example of a power transmission line 1 in which the power stations A and B have a power source and a neutral grounding resistance (NGR) of 200A, the power stations C and D have only a load, and there are branches B1 and B2 in two places. It is. Here, the master station 2 is placed at the electric power station A, the slave stations 3 to 10 are placed at appropriate intervals on the power transmission line 1, and the master station 2 and the slave stations 3 to 10 are optical fibers in the overhead ground wire. Assume that they are connected.

Assuming that a surge occurs at a point F1 of the transmission line 1 and a failure occurs, the surge propagates from the point F1 to each end. The fault currents I _g1 and I _g2 flow from the electric stations A and B having the power source toward the point F1. Surge propagates to the branch line where the electric stations C and D are placed, but no fault current flows. FIG. 4 shows the current value and phase of the surge in the transmission line and the fault current in each slave station. The slave stations 3 to 10 transmit the failure information generated as described above to the master station 2 (electricity station A) via the optical fiber in the overhead ground wire.

  When receiving the failure information, the slave station selection processing means 32 (FIG. 3, the same applies hereinafter) of the master station 2 groups the slave stations 3 to 10 according to a predetermined condition based on the current value and phase angle of the fault current. In the case of this example, the slave stations 3 and 4 (A group) having a current value of 200A and a phase angle of 0 °, the slave stations 5, 6, and 7 (B group) having a current value of 200A and a phase angle of 180 °, and a child having a current value of 0A Group into stations 8, 9, 10 (group C).

  Then, the surge detection times are compared in each group, rearranged in the order of the times, and the slave station having the earliest surge detection time in each group is selected. Here, the slave station 4 is selected in the A group, the slave station 5 is selected in the B group, and the slave station 8 is selected in the C group. As a result, the selected slave station number is sent to the surge occurrence point calculation processing means 33.

The surge occurrence point calculation processing means 33 calculates the surge occurrence point by the above equation (1) from the surge detection time of the slave station selected by the slave station selection processing means 32. In the case of this example, since there are three selected slave stations, the surge occurrence point is calculated by the following procedures 1 to 3.
Procedure 1: Calculate surge occurrence points for all combinations of the three slave stations.
Procedure 2: Select the two whose calculated surge occurrence points are close to each other.
Procedure 3: Calculate the average value of two surge occurrence points.

  In the procedure 1, all combinations of the three slave stations are the slave station 4-5, the slave station 5-8, and the slave station 4-8. The slave station 4-5 sandwiches the point F1, and when the surge occurrence point is obtained at the surge detection time of this combination, it becomes a point F11 (not shown) near the point F1. The slave station 5-8 also sandwiches the point F1, and when the surge occurrence point is obtained at the surge detection time of this combination, it becomes a point F12 in the vicinity of the point F1. Since the slave station 4-8 sandwiches the branch point B1, when the surge occurrence point is obtained at the surge detection time of this combination, it becomes a point B11 in the vicinity of the branch point B1.

  According to the procedure 2, the points F11 and F12 where the surge occurrence points are close to each other are selected. Next, according to the procedure 3, the average value of the points F11 and F12 is calculated as a surge occurrence point. In the procedure 3, the average value of the two surge occurrence points is calculated. However, in the procedure 3, the surge occurrence point having the smaller difference in the surge detection time may be set as the surge occurrence point.

  The failure point display selection processing means 34 checks the failure state flags of all the slave stations sent from the failure information receiving means 31, and if at least one failure state flag is "1", the surge occurrence point calculation processing means 33 Is displayed on the monitor 36 as a failure point to prompt the user to perform an emergency inspection.

  When the failure status flags of all the slave stations are “0”, the surge peak value is compared with a preset lightning strike determination level. Here, if even one of all the slave stations exceeds the lightning strike determination level, the overhead ground wire lightning strike point display is performed. In addition, when the lightning strike level is not exceeded in all the slave stations, a surge occurrence point is displayed as a surge occurrence without urgency. The lightning strike determination level is preferably a value calculated from a standard lightning strike current as an initial value, and then changed to a lightning strike determination level appropriate for the transmission line from a history of result recording described later. In the case of the example of FIG. 4, since a fault current has occurred and the fault status flag is “1”, the fault point is displayed.

  Further, every time the master station receives the failure information due to the occurrence of surge and calculates the surge occurrence point, the failure point display selection processing means 34 records the result and leaves it as a history. Then, statistical processing is performed after a predetermined period, and a graph display and numerical display are performed for the position of the failure point, overhead ground lightning strike point, surge occurrence point, and surge level.

  The user can inspect the transmission line in the area by determining the location where the failure, overhead ground lightning strikes and surges are frequently generated from the data and display of the statistical processing result. As a result, the power transmission line can be efficiently inspected before it breaks down, so that it is possible to detect damage particularly due to lightning strikes over the ground, and to prevent the failure in advance.

FIG. 5 shows an example when a surge occurs at a point F2 between the branch point B1 and the electric station C and a failure occurs. When a surge occurs at point F2 and a failure occurs, the surge propagates from point F2 to each end. Since the fault currents I _g1 and I _g2 flow from the electric power stations A and B having the power source toward the point F2, the fault currents I _g1 and I _g2 are added at the branch point B1. The lightning surge propagates from the point F2 to the branch line where the electric stations C and D are placed, but no fault current flows. FIG. 5 shows the current value and phase of the surge in the transmission line at this time and the fault current in each slave station. The slave stations 3 to 10 transmit the failure information to the master station 2 (electricity station A) via the optical fiber in the overhead ground wire.

  When receiving the failure information, the slave station selection processing unit 32 of the master station 2 groups the slave stations 3 to 10 into groups. In the case of this example, the slave stations 3 and 4 (group A) having a current value of 200A and a phase angle of 0 °, the slave stations 5, 6, and 7 (group B) having a current value of 200A and a phase angle of 180 °, and a current value of 400A It is grouped into a slave station 8 (C group) and current values 0A and 9 (D group).

  Then, the surge detection times are compared in each group, rearranged in the order of the times, and the slave station having the earliest surge detection time in each group is selected. Here, the slave station 4 is selected for the A group, the slave station 5 is selected for the B group, the slave station 8 is selected for the C group, and the slave station 9 is selected for the D group. In this case, since there are three or more selected slave stations, among the selected slave stations 4, 5, 8, and 9, three slave stations 8, 9, and 4 are selected in order from the earliest surge detection time, As a result, the selected slave station number is sent to the surge occurrence point calculation processing means 33.

  The surge occurrence point calculation processing means 33 calculates the surge occurrence point for all the combinations of slave stations according to the above procedure 1. In this case, the combination of the slave stations is a slave station 8-9, a slave station 4-8, and a slave station 4-9. The slave station 8-9 sandwiches the point F2, and when the surge occurrence point is obtained at the surge detection time of this combination, it becomes a point F21 in the vicinity of the point F2. The slave station 4-9 also sandwiches the point F2, and when the surge occurrence point is obtained at the surge detection time of this combination, it becomes a point F22 near the point F2. In the case of the slave station 4-8, since the point F2 is between the slave station 8 and the slave station 9, when the surge occurrence point is obtained at the surge detection time of this combination, the point F23 near the slave station 8 is obtained.

  Next, the points F21 and F22 where the surge occurrence points are close to each other are selected according to the procedure 2. Next, according to the procedure 3, the average value of the points F21 and F22 is calculated as a surge occurrence point. In this case as well, the smaller one of the two surge occurrence points may be the surge occurrence point.

  The failure point display selection processing means 35 causes the monitor 36 to display the failure point because a failure current has occurred and the failure state flag is “1”.

  FIG. 6 shows an example in which lightning strikes the overhead ground wire at point F3, but no failure occurs. When a lightning surge occurs at point F3, the surge propagates from point F3 to each end. In this case, no failure current or failure voltage is generated because there is no failure. In this case, the failure state flag in the failure information transmitted from the slave station is “0”, and the failure voltage information and the failure voltage information do not indicate a failure.

  The slave station selection processing means 32 compares the surge detection time of each slave station and the three slave stations 5, 6, 10 in order from the earliest surge detection time because the fault current information and fault voltage information do not indicate a fault. Select. Then, the selected slave station number is sent to the surge occurrence point calculation processing means 33.

  The surge occurrence point calculation processing means 33 calculates the surge occurrence point for all the combinations of slave stations according to the above procedure 1. In this case, a combination of the slave stations is a slave station 5-6, a slave station 5-10, and a slave station 6-10. The slave station 5-6 sandwiches the point F3, and when the surge occurrence point is obtained at the surge detection time of this combination, it becomes a point F31 in the vicinity of the point F3. The slave station 5-10 also sandwiches the point F3, and when the surge occurrence point is obtained at the surge detection time of this combination, it becomes a point F32 in the vicinity of the point F3. In the case of the slave station 6-10, since the point F3 sandwiches the branch point B2 between the slave station 6 and the slave station 10, when the surge occurrence point is obtained at the surge detection time of this combination, the vicinity of the branch point B2 It becomes point B33. Next, the points F31 and F32 that are close to the surge occurrence point are selected according to the procedure 2, and the average value of the points F31 and F32 is set as the surge occurrence point according to the procedure 3. Here, it is good also considering a direction with a smaller difference of surge detection time as a surge generation point among two surge generation points.

  The failure point display selection processing means 34 displays a surge occurrence point because no failure current or failure voltage is generated and the failure state flag is “0”. Further, the surge peak value is compared with the lightning strike determination level, and when it is determined that the lightning strike is detected, the monitor 36 displays the overhead ground wire lightning strike point.

  FIG. 7 shows another embodiment of the power transmission line fault location system according to the present invention. In this embodiment, a fault point is determined using a communication network of satellite communication in a power transmission line 1 in which the power stations A and B have a power source and a neutral grounding resistance (NGR) of 200A and there is no branch. It is a structural example. In the figure, slave stations 3 to 7 are arranged at an appropriate interval on the transmission line 1. In this case, FIG. 1 and FIG. 3 show that a satellite communication radio is used instead of the optical modem of the failure information transmitting means in the slave station, and a LAN module is used instead of the optical modem in the failure information receiving means of the master station. The point to use is different. Since other configurations are basically the same, illustration of a specific configuration example of the slave station and the master station is omitted, and the following description will be made using the same reference numerals as those in FIGS.

  If a surge occurs at point F4 and a failure occurs, the surge propagates from point F4 to each end. The fault current flows from the electric stations A and B where the power source is located toward the point F4. Each of the slave stations 3 to 7 detects a surge, a fault current, and a fault voltage, and sends the fault information as a mail to the master station 2 via the satellite 71, the earth station 72, the network management station 73, and the Internet.

  The slave station selection processing means 32 of the master station 2 is connected to the slave stations 3 to 6 (group A) having a current value of 200A and a phase angle of 0 °, and to the slave station 7 (group B) having a current value of 200A and a phase angle of 180 °. Divide into groups. Then, the surge detection times are compared in each group, rearranged in order of surge detection time, and the slave station with the earliest surge detection time in each group is selected. Here, the slave station 6 is selected in the A group, and the slave station 7 is selected in the B group. Since there are two selected slave stations, the selected slave station number is transmitted to the surge occurrence point calculation processing means 33. The surge occurrence point calculation processing means 33 calculates a surge occurrence point from the surge detection times of the two slave stations 6 and 7 using the above equation (1), and transmits it to the failure point display selection processing means 34.

  The failure point display selection processing means 34 causes the monitor 36 to display the failure point because a failure current has occurred and the failure state flag is “1”.

  In wireless communication such as satellite communication and mobile phone, the communication cost is a fee structure in which the packet charge is added to the basic charge, and the communication cost increases as the amount of communication data and the number of communication increases. In order to suppress an increase in communication cost, it is only necessary to select information to be transmitted with reference to the failure state flag in the slave station and transmit only necessary information. For example, if failure information is transmitted only when a failure occurs, only a few failures occur annually, so that packet charges become insignificant and communication costs can be greatly reduced.

  According to the present invention, even when a long line such as a power transmission line has a branch, a failure point can be relatively easily and accurately determined. In addition, the use of the fault status flag can distinguish and display fault surges, overhead ground line lightning surges, and induced lightning surges. In the case of a surge, an occurrence history is accumulated, and as a result, inspection of power transmission lines and overhead ground lines at locations where surges frequently occur can be promoted. As a result, failure inspection and preventive maintenance of the transmission line can be performed efficiently.

  Moreover, even when there is a branch in the transmission line, by calculating the surge occurrence point with all combinations of the three slave stations, it is not necessary to place the slave station at the branch point, and the fault point can be located effectively. . Furthermore, since transmission data can be selected depending on the occurrence of surges, it is possible to reduce communication costs when using wireless communication.

It is a block diagram which shows the structural example of the subunit | mobile_unit of the power transmission line fault location system which concerns on this invention. It is a wave form diagram at the time of becoming an electrical failure after lightning surge generation | occurrence | production. It is a block diagram which shows the structural example of the master station of the power transmission line fault location system which concerns on this invention. It is explanatory drawing of an example of operation | movement of the fault location system based on this invention. It is explanatory drawing of the other example of operation | movement of the fault location system which concerns on this invention. It is explanatory drawing of the further another example of operation | movement of the fault location system which concerns on this invention. It is a figure which shows other embodiment of the power transmission line fault location system which concerns on this invention. It is a principle diagram of a conventional surge orientation system. It is a principle diagram of another conventional surge locating system. It is a principle diagram of still another conventional surge localization system. It is a figure which shows an example of a structure of a power transmission line, and a lightning surge waveform.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transmission (distribution) electric wire, 2 ... Master station, 3-10 ... Slave station, 11 ... GPS receiving means, 12 ... Fault current detection means, 13 ... Fault voltage detection Means 14 ... Current / voltage monitoring means 15 ... Surge detection means 16 ... Fault information transmission means 17 ... Optical fiber 31 ... Fault information reception means 32 ... Slave station Selection processing means 33... Surge occurrence point calculation processing means 34. Fault point display selection processing means 35 35 Transmission line database 36. Monitor 71 71 Artificial satellite 72. -Earth station, 73 ... Network management station, 111 ... GPS antenna, 112 ... GPS receiver, 121 ... Current sensor, 122, 132, 152 ... Filter, 123, 133, 153 ..A / D converter, 124 ... Fault current detection , 132 ... Voltage sensor, 134 ... Fault voltage detector, 154 ... Surge detector, 161 ... Control CPU, 162 ... Memory, 163, 311 ... Optical modem, 312 ..Data formation processing section

Claims (4)

In a transmission line failure point locating system, which is arranged in a plurality of transmission lines and has a slave station that transmits information about the transmission line to a master station, and a master station that identifies a failure point based on information from the slave station.
The slave station is
GPS receiving means for receiving GPS radio waves from an artificial satellite and extracting the current time held by GPS;
Fault current detection means for detecting fault current flowing in the transmission line and outputting fault current information;
Fault voltage detection means for detecting fault voltage generated in the transmission line and outputting fault voltage information;
Current voltage monitoring means for sending a failure state flag corresponding to a change state of a failure current and a change state of a failure voltage immediately after a surge occurs in the transmission line; and
Surge detection means for taking out the surge detection time from the GPS receiving means and sending the surge detection time and surge peak value together with the failure state flag;
Failure information transmitting means for transmitting the surge detection time, the surge peak value, the failure state flag, the failure current information, and the failure voltage information to the parent station through the communication network as failure information,
The master station is
Failure information receiving means for receiving failure information from the failure information transmitting means;
A slave station selection processing means for selecting a slave station to be used for orientation based on the failure information;
Surge occurrence point calculation processing means for calculating a surge occurrence point using the surge detection time of the slave station selected by the slave station selection processing means,
A failure point display selection processing means for selecting a failure point display according to the failure state flag of the slave station used for the surge occurrence point calculation in the surge occurrence point calculation processing means ,
The slave station selection processing means detects the presence / absence of failure detection according to the state of the failure state flag. In the case of failure detection, the surge detection time is early among slave stations in which either the current value or the phase angle of the failure current is different. Two or more slave stations are selected from the ones, and when no failure is detected, two or more slave stations are selected from the ones with the earlier surge detection time, and the surge generation point calculation processing means includes the slave station When there are three or more slave stations selected by the selection processing means, three of the selected slave stations with the earliest surge detection time are selected, and the surge occurrence point is calculated by all three combinations. The average point of two surge occurrence points that are close to the surge occurrence point is taken as the surge occurrence point, or the two surge occurrence points that are close to the calculated surge occurrence point are those with the smaller difference in surge detection time. characterized in that the generation point Transmission line fault point location system to be. 2. The transmission line fault location system according to claim 1, wherein in the slave station, the failure information transmitted by the failure information transmission unit can be selected according to the failure state flag. The slave station selection processing means divides the slave stations into groups according to the fault current information and the fault voltage information, arranges them in order of surge detection time for each group, and selects a slave station having the earliest surge detection time in each group. The transmission line fault location system according to claim 1. 2. The transmission line failure point location system according to claim 1, wherein an aerial ground lightning point that does not cause a failure is located in the master station based on a combination of the failure state flag and the surge peak value .

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