JP6817521B2 - Single point of failure indicator - Google Patents

Description

The present invention relates to a transmission line failure point determination system.

The surge arrival time difference type failure point identification method identifies the position of the surge occurrence point from the difference in the elapsed time until the surge wave generated in the event of a transmission line accident is detected by the observation devices installed at both ends of the transmission line. If the propagation speed of the surge wave and the line length are set correctly, the standardization can be performed regardless of the line constant at the commercial frequency, and the standardization result can be obtained with sufficient accuracy.

However, there are not only accidents such as lightning where surges are likely to occur, but also accidents such as tree contact where surges are unlikely to occur, and there is a drawback that it may not be possible to locate or the orientation result may contain a very large error. there were.

In addition, a surge may occur even if it is not an accident such as when opening and closing a circuit breaker, and it is difficult to distinguish between an accident and a non-accident.

In addition, in the case of an accident outside the section behind the power transmission end, the surge arrival time difference type failure point indicator only observes the propagation time difference between the power transmission and reception ends, so it may be mistaken for an accident at or near the power transmission end. There was. In addition, if there is an error in the set propagation speed, it may be mistaken as an accident within the section even though it is outside the section.

On the other hand, the conventional impedance-type single point of failure determination method has parameters that cannot be accurately grasped, such as the ground return resistance value at the time of a ground fault, so it is unlikely to deviate significantly, but it has the disadvantage that a certain error can always be included. .. In addition, when there are multiple branches of the transmission line, the calculation becomes complicated, and a calculation method such as formulating the whole using the Kirchhoff's formula as in Patent Document 3 and performing a matrix calculation to determine the failure point is used. There is a need to.

In Patent Document 1, in [claim 3], waveform data is sampled by a second sampling circuit having a sampling frequency lower than the sampling frequency of the first sampling circuit, and the waveform data sampled by the second sampling circuit is used. It is written that the effective voltage value or the effective value of the current of the commercial frequency component is obtained by the effective value calculation means, and when it is equal to or less than the predetermined voltage value or more than the predetermined current value, it is determined that an accident has occurred.

In Patent Document 2, in [Claim 1], a commercial frequency component detection unit that extracts and outputs an accident current in a commercial frequency band with a low-pass filter and a surge current having a higher frequency than the commercial frequency band are extracted and output by a high-pass filter. The accident point distance is determined by calculating the time difference between the surge current component detection unit that detects the surge current component, the accident section detection unit that detects the accident section based on the accident currents of multiple cycles, and the surge current reaching each optical current sensor. An accident point locating device having an accident point locating unit is written, and in [Claim 2], the accident point locating that outputs the accident point information indicating the accident point only when the accident section detecting unit detects the accident section. The device is written.

Certainly, unlike the conventional surge waveform arrival time difference type failure point locating device in which the failure point locating system of Patent Document 1 performs failure point calibration each time a surge is detected, it is calibrated only when a ground fault or short circuit accident occurs. Therefore, the number of false indications at the time of non-accident has decreased.

However, even if an accident occurs outside the target section of the target, a voltage drop or overcurrent will occur, and since the standarding will be performed with the surge arrival time difference, the accident on the power supply side far before the power transmission end and the distance from the power reception end will be further. There was a problem that the accident on the load side was erroneously labeled as an accident at or near the power transmission end or the power reception end.

Further, in the accident point locator of Patent Document 2, in the case of an underground cable system in which the neutral point is grounded at both the power transmission end and the power reception end, the surge current at the time of a ground fault is from the accident point to both the power transmission end and the power reception end. Since the ground fault current flows from both the transmitting end and the receiving end toward the accident point, the method of [claim 1] of Patent Document 2 is established, but an overhead transmission line operated by a single line of a low voltage system. In this case, the power receiving end is often not grounded at the neutral point, and therefore there is a problem that a ground fault current or a surge current at the time of a ground fault hardly flows at the power receiving end, and the above-mentioned Patent Document 2 [Claim 1] Method cannot be used.

Further, the accident point locating device of Patent Document 2 requires a dedicated optical fiber for transmitting current surge waveform information from the power transmitting end and the power receiving end to the accident point locating device, and the equipment becomes expensive. Further, although not particularly described in Patent Document 2, it is necessary to consider the propagation delay time of the surge waveform information in the optical fiber at the time of localization.

In addition, the fact that multiple cycles of commercial frequency waveform data is required to determine the presence or absence of an accident means that the time equivalent to one cycle of the commercial frequency x the time equivalent to the number of multiple cycles is required, and the surge waveform information is available. It is necessary to wait for several tens of msec after it arrives in about several tens of μsec, but during that time, surge waveforms can occur sporadically and reflected wave surges can also reach, so in order to correctly identify and retain the leading surge information. It is necessary to devise.

To summarize the above, the error is small if the surge arrival time difference type failure point identification method is applied, but when a surge with sufficient amplitude does not occur, in the case of an out-of-section accident, in the case of a non-accident such as a circuit breaker opening / closing surge. When it is localized by the surge that has occurred, it is often misidentified, and if it deviates, the error is very large.

On the other hand, although it is difficult to obtain a large error in the conventional impedance type failure point calibration method, there is a drawback that a constant error can always be included because there are some parameters such as the ground return resistance value that cannot be set accurately. is there. In addition, if the number of receiving ends increases due to the branching of the transmission line, the localization calculation becomes complicated.

According to the invention of Patent Document 1, it was possible to avoid erroneous localization at the time of non-accident in the surge arrival time difference type failure point identification method, but the other problems described above remain. Further, according to the invention of Patent Document 2, erroneous localization in an accident outside the section can be avoided, but erroneous localization in the case where the above surge does not occur is unavoidable. Further, the method of Patent Document 2 cannot be used in the case of a single-line transmission line in which the power receiving side is a neutral point non-grounded type such as a low-voltage overhead transmission line.

Patent No. 40444489 Patent No. 5991840 Patent No. 3756026

In view of these points, the problem to be solved by the present application is that while taking advantage of the characteristics of the surge arrival time difference type failure point grounding method that can obtain highly accurate grounding results, erroneous grounding and surges in accidents outside the target section of the grounding occur. The purpose is to provide a fault point positioning system at low cost that can be used even in an overhead transmission line system in which the power receiving end is not grounded at the neutral point, while preventing erroneous positioning in the case of an accident that has not occurred.

The inventor of the present application focused only on finding the position where a ground fault accident or a short circuit accident occurred, and did not focus on grasping the accident situation, so that in the case of an out-of-section accident or a non-accident. In view of the fact that the accident was accurately grasped and the accident situation was determined, whether it was a ground fault or a short circuit accident, and in which phase the accident occurred, and then the location of the accident was determined. I thought it should be calculated.

Therefore, the inventor of the present application saves the changes in the surge waveform and the commercial frequency waveform when they are detected as shown in the flow diagram of the activation detection unit in FIG. 4-1. The arrival time of the surge waveform and the detection time of the change in the commercial frequency waveform. From the commercial frequency waveform data, the voltage value, current value, and phase information of each phase, as well as the presence or absence of an accident and the accident situation indicating the accident situation (such as A-phase one-line ground fault or AB-phase two-wire short circuit) When a ground fault or short-circuit accident is determined by automatically calculating and determining (a term indicating the accident situation consisting of the accident phase name and the accident type), a surge is performed as shown in the control flow diagram of FIG. 4-2. After confirming that the waveform can be detected with a sufficient amplitude exceeding the set threshold and the waveform data is saved, the accident position is specified from the difference in the arrival time of the surge waveform to the power transmission / reception end, and the amplitude of the surge waveform. If the data is not recorded or the arrival time is unclear even if the data is recorded, the failure point is determined from the voltage value, current value, and phase information of each phase calculated from the commercial frequency waveform data. It was decided to standardize.

Generally, in order to observe the surge waveform correctly, a dedicated sensor is installed near the transmission line, and the obtained surge waveform data is subjected to voltage / frequency conversion (or V / F conversion) with a conversion module, and then optical fiber, etc. It was necessary to transmit to the installation location of the accident point locator.

However, there is a demerit that it costs a considerable amount to install a sensor near the transmission line of a substation or an optical fiber dedicated to waveform data transmission, which is a surge waveform arrival time difference type accident point locator. It was also the reason why the introduction of

However, at substations, waveform recorders for observing and recording accident phenomena such as ground faults and short-circuit accidents are voltage converters (PD, PT or VT) and current transformers (CT) under transmission lines. ) Is always installed as an existing facility in the secondary circuit.

In the present application, a high-frequency surge waveform is also recorded by the waveform recorder, and it is verified whether the accident point can be determined from the arrival time difference. Among them, the surge waveform of the primary side circuit such as the voltage converter PD, which is often used, and the surge waveform of the secondary side circuit were compared.

As a result, as shown in FIG. 5, although the waveform of the secondary circuit contains an extra vibration component as noise compared to the waveform of the primary circuit, the rising timing of the surge waveform is well matched. I understand.

Therefore, by simply adding a function to record a high-frequency surge waveform to the voltage / current waveform recorder of the transmission line normally installed in the substation, the surge arrival time difference method can determine the accident point with sufficient accuracy, and the vicinity of the transmission line. It turned out that there is no need to install a new voltage / current sensor.

This is because in the conventional measurement of the arrival timing of the surge waveform, the surge waveform must be transmitted by installing a dedicated surge sensor at the site, performing voltage-optical conversion, etc., and connecting the cable to the recording device with a dedicated optical fiber. This overturns the common wisdom that accurate surge waveform measurement is not possible, and is a factor in the present invention that can provide an apparatus for determining failure points from observation results of both surge waveforms and commercial frequency waveforms without incurring a large cost. It was.

Based on the above contents, the configuration of the device of the present application is a configuration in which a surge waveform recording function is added to the existing commercial frequency waveform recorder.
That is, a commercial frequency waveform input having a low-speed A / D converter that inputs a voltage or current waveform, samples at a relatively low sampling frequency of several tens to several hundred times the commercial frequency, and performs A / D conversion. Department and
A surge waveform having a high-speed A / D converter that inputs only the surge waveform component excluding commercial frequency components, harmonics, and high-frequency noise components, samples at a relatively high sampling frequency of several MHz or higher, and performs A / D conversion. Has an input section,
Furthermore, a pre-accident waveform memory that stores A / D-converted waveforms and
A start detector that detects accidents such as voltage drop and overcurrent with low-speed sampling data,
The contents of each pre-accident waveform memory that stores the low-speed and high-speed sampled waveform data that was stored at the time of activation detection and the waveform data obtained by observing for a certain period of time after that are transferred and stored in each main memory. Surge waveform recording unit, commercial frequency waveform recording unit, and
A waveform recording device having a data transmission unit that transmits data stored as a request from the outside and a waveform data stored at the time of accident detection by issuing a request to the waveform recording device are collected and a failure point is analyzed. Analytical device and
It is provided with a monitor device for displaying the analysis result by the analysis device.

Further, the first invention of the present application is a failure point determination system having the above configuration, which is calculated from a failure point identification function for obtaining a distance from a time difference of the rise time of the surge waveform component to a failure point, and commercial frequency waveform data. It has a failure point identification function that determines the failure point from each phase voltage value, current value, and phase information, and when a surge is found to occur, the distance from the surge waveform component arrival time difference to the failure point is obtained. In the event of an accident in which no surge is observed, the failure point determination system is characterized in that the failure point is determined from the voltage value, current value, and phase information of each phase calculated from the commercial frequency waveform data.

Further, the second invention of the present application is a failure point determination system having the above configuration, and in the event of an accident in which the occurrence of a surge is recognized, the effective voltage value or current of the commercial frequency component of the waveform data sampled by the commercial frequency waveform input unit. The effective value of the phase voltage obtained by the start-up detection unit is obtained by the start-up detection unit, and the effective value of the phase voltage obtained by the above-mentioned start-up detection unit is less than or equal to the voltage value set separately (and in the case of the resistance ground system, the effective value of the zero-phase voltage is set separately. When the effective value of the line current (or line-to-line current) obtained by the start detection unit is equal to or higher than the voltage value), it is determined that the start detection unit has detected an accident, and immediately before Failure point identification is characterized in that the surge waveform data input to the surge waveform input unit is determined to be valid accident surge waveform data, and the distance from the time difference of the rise time of the surge waveform component to the failure point is obtained. It is a system.

Further, the third invention of the present application is a fault point determination system having the above configuration, and data obtained by sampling at a relatively low sampling frequency of about several tens to several hundreds times a commercial frequency (hereinafter, low-speed sampling). When a voltage drop or overcurrent is detected in (referred to as data), the vector amount (effective value and phase angle) as the AC waveform is obtained from the current waveform of the low-speed sampling data between the detected phases or lines, and the current is Based on the effective value and the phase angle value, the amount of current vector flowing from the transmitting end to the receiving end (the case where the current flows from the transmitting end to the receiving end is considered to be positive), and the current flowing from the receiving end to the transmitting end. When the amount of current vector (the case where the current flows from the receiving end to the transmitting end is regarded as positive) is calculated, and it can be recognized that the sum of the current vectors is not significantly zero (there is no zero beyond the range of error). It is a failure point locating system characterized by locating a failure point assuming that there is an accident point where current flows out within the range from the power transmission end to the power reception end.

Further, the fourth invention of the present application is a failure point determination system having the above configuration, and is detected when a decrease in phase voltage, an increase in zero-phase voltage, and an overcurrent of line current are detected in the low-speed sampling data. Obtain the vector amount (effective value and phase angle) as the AC waveform from the voltage waveform and current waveform of the low-speed sampling data between the phases or lines, and based on the effective value and phase angle value of the voltage and current. The impedance vector amount (phase impedance complex number vectors Za, Zb, Zc and line impedance complex number vector Zab, Zbc, Zca) seen from the power transmission end to the power receiving end side is calculated, and the impedance complex number vector amount (hereinafter abbreviated as impedance vector) is calculated. ) Is inside the quadrangle indicating the determination region on the impedance plane of FIG. 3 , it has a function of determining that the phase is the accident phase, and it is characterized in that the failure point is determined using the data of the accident phase. It is a failure point determination system.

According to the present invention, it is possible to avoid erroneous localization in the case of an accident in which almost no surge occurs, and it is also possible to avoid erroneous localization in the case of non-accident. In addition, erroneous marking due to an accident outside the target section can be avoided. According to the present invention, the accident phase can be identified from the analysis result of the vector amount of the AC waveform, and the surge waveform data of the accident phase can be used for standardization. Therefore, if a surge is detected, the data of any phase can be unconditionally standardized. Positioning accuracy is improved compared to the case where it was used. In addition, since a function is added to the existing waveform recorder at the substation to record surge waveforms, a dedicated surge sensor may be installed directly under the transmission line, or a dedicated communication means such as an optical fiber may be installed. It is possible to provide a surge waveform / commercial frequency waveform combined accident point (or failure point) locating device at low cost.

Block diagram of the entire system Example of single-line connection diagram of the system to be mapped Impedance screen for accident phase and accident phase determination Start detection flow diagram Positioning calculation flow chart Surge waveform example of primary side circuit and secondary side circuit of voltage converter (PD or PT) Example of localization calculation method by impedance method

The embodiments of the present application will be described in detail below. FIG. 1 is a conceptual diagram showing the entire system of the present application.

As shown in FIG. 1, the failure point determination system of the present embodiment is arranged via the waveform recording devices 100-1 and 100-2 provided at the A end and the B end of the transmission line 10 and the communication network 400. It is composed of an analysis device 200 and a monitor device 300.

The waveform recording devices 100-1 and 100-2 are installed at both ends of the transmission line 10 and input the voltage or current waveform as it is or via the anti-aliasing filter 102, and are tens to hundreds of commercial frequencies. Only the commercial frequency waveform input unit 170 having a low-speed A / D conversion unit 110a that samples at a relatively low sampling frequency of about twice and performs A / D conversion, and the surge waveform component excluding the commercial frequency component and high-frequency noise component are input. It also has a surge waveform input unit 180 having a high-speed A / D conversion unit 110b that samples at a relatively high-speed sampling frequency of about several MHz or more and performs A / D conversion, and stores the A / D-converted waveform. Pre-accident waveform memory 120, activation detection unit 130 that detects accidents such as voltage drop and overcurrent with low-speed sampling data, and accidents that store low-speed and high-speed sampled waveform data stored at the time of activation detection. The surge waveform recording unit 181 and the commercial frequency waveform recording unit 171 that transfer and store the contents of the previous waveform memory 120 and the waveform data obtained by observing for a certain period of time thereafter to the main memory 140, and store that there is an external request. It has a data transmission unit 160 that transmits the data and receives the activation determination threshold data.
Since the configuration of the waveform recording device 100-2 arranged at the B end of the transmission line 10 is the same as that of the waveform recording device 100-1 described above, the description thereof will be omitted.

Further, the analysis device 200 (also referred to as a server device) issues a request to the waveform recording devices 100-1 and 100-2, collects the waveform data stored at the time of accident detection, and analyzes the failure point. (See FIG. 1) On the other hand, the monitoring device 300 (also referred to as a client device) receives data from the analysis device 200 and displays the data on the screen, and also passes through the analysis device 200 and the analysis device 200 to record the waveform 100-1, It is a man-machine interface that issues a command to 100-2 to select data and request it.

Although each of these devices is connected through the communication network 400 to construct a failure point locating system, the functions of each of these devices are integrated into one failure point locating device without going through the communication network 400. You may.

Further, the analysis device 200 is a failure point locating device that obtains a failure point from the time difference of the rising (or falling) time of the surge waveform component in the waveform data received from the waveform recording devices 100-1 and 100-2. Alternatively, it is a component that constitutes a failure point determination system.

The voltage and current waveforms of the transmission line 10 can be input to the measuring instrument (such as 63.5V or 5A) by the voltage converter 21 (referred to as PD, PT or VT) and the current converter 22 (referred to as CT) in the substation 20. It is converted into a value and input to each device in the substation. The waveform recording devices 100-1 and 100-2 of the present application are one of the devices.

In the waveform recording devices 100-1 and 100-2, the voltage and current signals are usually converted into alternating current of about 5 Vrms and input to the A / D converter. In the device of the present application, the signal is high-pass filtered by the high-pass filter 101, and the AC waveform component of the commercial frequency and the harmonic component up to several tens of orders are removed, and the frequency component waveform of 100 kHz to 1 MHz is sampled at a sampling frequency of about several MHz. The surge waveform input unit 180 for A / D conversion and the commercial frequency waveform input unit 170 for A / D conversion of the AC waveform component of the commercial frequency at a sampling frequency of about several kHz after low-pass filtering by the anti-aliasing filter 102. Have.

Waveform data at both ends (A end, B end) of the transmission line 10 is sent from the waveform recording devices 100-1 and 100-2 to the analysis device 200 (server device) via the communication network 400, and is sent by the analysis device 200. The fault point localization calculation is performed.

According to the failure point locating system of the present embodiment, the analysis device 200 determines the failure point, and the output means outputs the result to the monitoring device.

The failure point determination by the analyzer is performed according to the flow of FIG. 4-2. This flow chart will be described below.

First, if low-speed sampling waveform data in the commercial frequency waveform input unit 170 is recorded at both the power transmission end and the power reception end, the current data of both phases are compared to check if there is any current leakage between the transmission and reception ends. If there is a leak, it is determined that the phase is the accident phase and there is an accident within the target section. If there is no current leakage, it is determined that there was no accident.

Although the above low-speed sampling waveform data is recorded at the power transmission end, if the data at the power reception end is not recorded at all power reception ends, the accident phase / accident section is based on the impedance value of each phase or line between the power transmission ends. To judge.

If it is determined that there is an accident in the section subject to localization, if surge waveform data is recorded at both the power transmission and reception ends, it is standardized by the arrival time difference of the surge waveform, and if surge waveform data is not recorded even in one place, low-speed sampling is performed. The fault point is defined using the impedance value based on the data.

The specific orientation calculation method based on the surge arrival time difference is shown below.

For example, suppose that the single-line connection diagram of the transmission line to be positioned is a typical transmission line model having one branch line as shown in FIG. (If there are multiple branch lines, it can be defined in the same way.)

Now, there is an accident at the branch line to the C substation, the distance from the branch point to the accident point is ΔX [km], the surge arrival time to the A substation is t ₁ [sec], and the surge to the B substation. The arrival time is t ₂ [sec], the surge arrival time at the C substation is t ₃ [sec], the surge propagation speed at the branch line is V _x [km / s], and the surge propagation time at the trunk line is T _AB [sec]. ].

Then, it can be seen that the value of (t1 + t2) is equal to twice the time required for the surge to pass through the part of ΔX and the sum of the time required for the surge to pass through the trunk line from end to end.

t ₁ + t ₂ = 2 x (ΔX / V _x ) + T _AB (1)

For the C substation, (2) holds, so subtract this double from the sides of equation (1).
Equation (3) is obtained.
t ₃ = (L _{x −} ΔX) / V _x (2)
(t ₁ −t ₃ ) + (t ₂ −t ₃ ) = 2 × (2 × ΔX−L _× ) / V _x + T _AB (3)

Than this,
ΔX = {(t _{1 −} t ₃ ) + (t ₂ −t ₃ ) −T _AB } × V _x / 4 + Lx / 2 (4)

Incidentally, the surge propagation velocity V _x of the branch line to the C substations from and B substation to C substation, if the surge passage time to the A substation respectively T _BC and T _CA from C substation,

V _x = 2 x L _x / (T _BC + T _CA- T _AB ) (5)

Therefore, by substituting this into Eq. (4), the distance ΔX from the branch point to the C substation to the accident point on the branch line can be found.

On the other hand, when defining the failure point from the voltage value, current value, and phase information of each phase calculated from the commercial frequency waveform data, the failure point is viewed from the commercial frequency waveform data, and in the case of a ground fault, the failure point is viewed from the transmission end. Calculate the impedance value between the transmission line and the ground, and in the case of a short-circuit accident, the impedance value between the transmission lines from the transmission end to the failure point, and from that value and the impedance value of the entire length of the transmission line to the accident point. You can find the distance.

An example of the calculation method is shown in FIG. There are many methods for determining the failure point from the voltage value, current value, phase angle information, etc. of each phase calculated from the commercial frequency waveform data, and FIG. 6 is an example thereof. Other methods may be used.
In FIG. 6,
i _s: complex line current during the non-fault accident phase in the sending end (the transmission direction as positive.)
_ir : Complex line current at the power receiving end when the accident phase is non-accident (the power receiving direction is the negative electrode)
i _'s: complex line current at the time of the accident of the accident phase in the sending end (the transmission direction as positive.)
_i'r : Complex line current at the time of the accident in the accident phase at the power receiving end (the power receiving direction is the negative electrode)
.Delta.i _s: complex fault current at the sending end which is added during the accident (the power transmission direction is positive.)
.Delta.i _r: complex fault current at the receiving end to be added at the time of the accident (the power receiving direction is negative.)
_if : Complex accident current at the accident point (outflow direction is positive)
v _'s: complex voltage during non fault accident phase in the sending end (the power transmission line side is positive polarity ground reference.)
_v'r : Complex voltage at the time of non-accident phase at the power receiving end (the transmission line side is positive based on the ground)
v _'s: complex voltage during non fault accident phase in the sending end (the power transmission line side is positive polarity ground reference.)
_v'r : Complex voltage at the time of non-accident phase at the power receiving end (the transmission line side is positive based on the ground)
r _f : Accident point resistance value v _f : Accident point complex voltage (The transmission line side is positive with respect to the ground)
Z: Line complex impedance over the entire length of the accident phase R: Line resistance over the entire length of the accident phase X: Line reactance over the entire length of the accident phase L: Overall length k: Accident point from the transmission end ( Or the value obtained by dividing the distance to the fault point by the total length L kL: The distance from the transmission end to the accident point (or fault point)
arg (Z): Argument of complex number Z
Imag (z): imaginary part Z of complex number Z ^* : conjugate complex number of complex number Z

When there are branch lines and there are a plurality of power receiving ends, the method of Patent Document 3 may be applied, but the number of line constants and the like increases, and the localization calculation becomes complicated.

10 Transmission line 20 Equipment in the substation of the transmission line 21 Voltage converter PT, PD or VT
22 Current converter CT
100-1, 100-2 Waveform recording device 101 High-pass filter 102 Anti-aliasing filter 110a Low-speed A / D converter 110b High-speed A / D converter 120 Pre-accident waveform memory 130 Start detection unit 140 Main memory 160 Transmission unit 200 Analyzer 300 Monitor device 400 Communication network

Claims (4)

A commercial frequency waveform input unit having a low-speed A / D converter that inputs a voltage or current waveform, samples at a relatively low sampling frequency of several tens to several hundred times the commercial frequency, and performs A / D conversion.
A surge waveform having a high-speed A / D converter that inputs only the surge waveform component excluding commercial frequency components, harmonics, and high-frequency noise components, samples at a relatively high sampling frequency of several MHz or higher, and performs A / D conversion. Input section and
A pre-accident waveform memory that stores A / D-converted waveforms, and
A start detector that detects voltage drop and overcurrent accidents with low-speed sampling data,
The contents of each pre-accident waveform memory that stores the low-speed and high-speed sampled waveform data that was stored at the time of activation detection and the waveform data obtained by observing for a certain period of time after that are transferred and stored in each main memory. Surge waveform recording unit, commercial frequency waveform recording unit, and
A waveform recording device having a data transmission unit that transmits data stored as a request from the outside, and a waveform recording device.
It is provided with an analysis device that issues a request to the waveform recording device, collects waveform data stored at the time of accident detection, and analyzes a failure point, and a monitor device that displays the analysis result by the analysis device.
A failure point identification function that obtains the distance from the rise time of the surge waveform component to the failure point, and a failure that determines the failure point from the voltage value, current value, and phase information of each phase calculated from commercial frequency waveform data. It has a point localization function, and when a surge is found, the distance from the surge waveform component arrival time difference to the failure point is calculated, and when a surge is not found, each phase is calculated from the commercial frequency waveform data. A fault point locating system characterized by locating a fault point from each of the voltage value, current value, and phase information of.
In the fault point determination system according to claim 1, in the event of an accident in which a surge is observed, the effective voltage value or line current of the commercial frequency component of the waveform data sampled by the commercial frequency waveform input unit is obtained. , The effective value of the phase voltage obtained by the above start detector is less than or equal to the separately set voltage value (and in the case of a resistor ground system, the effective value of the zero phase voltage is more than or equal to the separately set voltage value), or the line current ( Alternatively, when the effective value of (line current) is equal to or greater than the separately set current value, the start detection unit determines that an accident has been detected, and the surge waveform data input to the surge waveform input unit immediately before is used as an effective accident surge. A failure point locating system characterized in that it determines that it is waveform data and obtains the distance from the failure point from the time difference of the rise time of the surge waveform component. The failure point identification system according to claim 1, wherein the voltage is lowered by the data obtained by sampling at a relatively low sampling frequency of about several tens to several hundred times the commercial frequency (hereinafter referred to as low-speed sampling data). At the time when or overcurrent is detected, the vector amount (effective value and phase angle) as the AC waveform is obtained from the current waveform of the low-speed sampling data between the detected phases or lines, and the effective value and phase angle of the current are calculated. Based on the values, the amount of current vector flowing from the transmitting end to the receiving end and the amount of current vector flowing from the receiving end to the transmitting end are calculated, and the sum of the current vectors is not significantly zero (beyond the error range). A claim characterized by having a start-up detection unit characterized by adding a function of detecting an accident as if there is an accident point within the range from the power transmission end to the power reception end when it can be recognized that there is no zero). The failure point identification system according to 1. In the failure point determination system according to claim 1, when a decrease in phase voltage, an increase in zero-phase voltage, and an overcurrent of line current are detected in the low-speed sampling data, between the detected phases or lines. Obtain the vector amount (effective value and phase angle) as the AC waveform from the voltage waveform and current waveform of the low-speed sampling data, and based on the effective value and phase angle value of the voltage and current, from the power transmission end to the power receiving end side. calculating the impedance vector quantity viewed, the impedance vector quantity harm impedance inside the rectangle indicating the determination area on a plane (PT, impedance values viewed fault point from the sending end which is calculated in the secondary conversion value CT Of these, the impedance is in the region less than twice the impedance value generated by the power transmission line to be positioned, and the resistance value is minus 1 to the resistance value equivalent to the flow of a current equivalent to twice the CT secondary rated value. The region above the value multiplied by, and the region above the straight line that has an inclination of 150 degrees counterclockwise from the positive direction of the real axis through the origin in the impedance plane, and on the real axis. The area above the straight line that has an inclination of 75 degrees counterclockwise from the positive direction of the actual axis through the point corresponding to the resistance value corresponding to the flow of current equivalent to twice the CT secondary rated value) . For example, a failure point locating system having a function of determining that the phase is an accident phase and locating a failure point using the data of the accident phase.