JPH0743410A - Trouble detection/location apparatus for uni-phase high voltage transmission line - Google Patents

Abstract

PURPOSE:To detect short-circuiting, ground fault and disconnection by arranging computers at both end of a transmission line respectively to pick up voltage/ current information constantly with the computers. CONSTITUTION:Computers 4m and 4s are set at both of a power transmission end and a power transmission terminal to monitor information on the condition of power transmission constantly and picks up and store the information as monitoring data to detect a trouble by analyzing the data stored. When measurement is started, a waveform value is taken into the main computer 4m (4s) via a sample folder 2m (2s) or the like from an input section 1m (1a) in which all the information is subjected to a photoelectric conversion from a voltage signal to amplify to check each wave for abnormality. When abnormality is determined with the computer 4m, an instruction of stopping the measurement is sent to an opponent computer 4s through a circuit 7. Thereafter, a trouble counter value is reported to the computer 4s through a circuit 6 via a communicator 5 from the computer 4m.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-phase high-voltage distribution line fault detecting / locating device for detecting a fault occurring in a non-grounded single-phase high-voltage distribution line and locating a fault location. The present invention relates to a synchronization method when simultaneity of failure information is required.

[0002]

2. Description of the Related Art Major faults of high-voltage distribution lines are roughly classified into line short-circuit faults, ground faults, and wire breakage faults. If any of these faults occurs, there is a risk of a secondary disaster caused by the fault. Therefore, it is obliged to stop the power distribution immediately.

When a high-voltage distribution line is broken and the suspended wire is a bare wire in the past, and when the bare wire hangs down on a general low-resistance ground, a low-resistance ground fault occurs. In the case of such a low resistance ground fault, a low resistance element such as a tree or metal body contacts between the ground of the distribution line and its resistance is several k.
In the case of a low resistance ground fault of Ω or less, it was possible to detect it with a conventional relay.

However, in the revision of the electrical equipment technical standard in 1977, bare wires are prohibited (insulated electric wires are laid) from the viewpoint of preventing electric shock accidents and ensuring the stability of supply. Came to be. Compared to bare wire, this insulated wire has an insulating layer, which exposes the property of being prone to breakage due to lightning damage, and many cases have been seen. Since there were many cases of wire breakage to whole wire breakage due to cracking, there were more wire breakage accidents than before.

Conventionally, in the case where a distribution line hangs at a high resistance location such as snow, dry grass / grass, or dry stone, there has been a case in which even a bare wire has a high resistance grounding of several kΩ or more. .

Therefore, in addition to the above accident, lightning damage disconnection,
When a high-voltage cable hangs due to a disconnection accident due to a stress corrosion cracking disconnection, the insulation layer is in a form intervening in the ground, so that it is structurally a high resistance ground. In addition, since there is an insulating skin layer, it may occur that the wire is disconnected in the air and continues to be crossed, and in that case as well, since the space insulation exists between the ground and the distribution line, the insulating skin layer with the insulation effect will provide the insulation effect. It has higher insulation than it has, and provides high resistance grounding of several kΩ or more.

As a result, the conventional relay, which could operate with low resistance grounding, cannot operate, and the power distribution continues even after the disconnection accident occurs. If humans or animals touch the hanging wire, not only an electric shock accident but also an additional accident will occur. Since power is supplied from the piezoelectric wire, a secondary disaster may occur.

As described above, the number of cases of disconnection accidents and high resistance accidents has increased, and various devices have been developed to detect such disconnection failures and high resistance ground faults of several kΩ or more. Among these wire disconnection accidents, a wire disconnection detection device focusing on lightning damage wire disconnection accidents is installed. This lightning damage disconnection detection method was developed with the idea that if a short circuit fault due to a simultaneous ground fault of different phases develops due to lightning, the short-circuit current will disconnect the high-voltage line. Since it does not operate unless it is done, there is a drawback that only disconnection due to such a short circuit / ground fault simultaneous phenomenon can be captured.

On the other hand, as a method capable of coping with a general disconnection accident, the fact that the ground voltage is unbalanced on the power receiving side located before the disconnection accident point is used.
The V ₀ generated due to the imbalance is detected, it is determined that there is a disconnection accident, the V ₀ power is used as a power source, and the disconnection information is transmitted to the distribution side as the accident information by the distribution line transportation method, and the distribution is stopped. There is a way to do it.

However, since the residual unbalanced voltage changes as the line conditions change, there is a disadvantage that the disconnection accident determination device must be improved in hardware each time.

As disclosed in (Japanese Patent Publication No. 5-19375), detection of a disconnection accident in a single-phase section of a three-phase power distribution of a three-phase circuit has been announced. However, when the three-phase circuit and the single-phase circuit are distributed from an insulation transformer insulated by an insulation transformer, there is a drawback that the method cannot be applied.

The distribution of the phase difference calculated at each measurement point is obtained as seen in (Japanese Patent Laid-Open No. 4-331418),
A method has been announced for determining a faulty section from a measurement point where the phase difference changes by approximately 180 °. However, this method has a drawback that it requires a measurement sensor, a transmission device for transmitting information from the measurement point, and a transmission line at each measurement point.

Generally, as a synchronization method when it is necessary to synchronize the failure information at a plurality of points, constant clock time information or time information is sent to a plurality of points through a clock line, and the parent information thereof is sent. A method has been adopted in which a plurality of child clocks always keep their clocks based on the clock information, but in this case, a transmission device, a receiving device, and a time adjusting device between the parent clock and the child clocks are required. There is.

Further, a slight ground fault due to a tree obstacle, a flying object, etc. due to the sway of the wind (the fault disappears by a short-time ground fault energy from the occurrence of the fault to the opening of the circuit breaker, or the flying object is scattered by the wind). For example, a ground fault that lasts for a short period of time, as typified by a ground fault in which the fault condition is removed by an external factor such that insulation between the ground is restored and redistribution is successful, is added again. There is a drawback that the fault location method of the pressure method cannot be applied.

The minor ground fault that has been temporarily removed may be left in place as a reoccurring reserve army fault and may recurrence, so it is expected to find the faulty part early. However, the re-pressurization method has a drawback that the fault location method cannot be applied since the micro-ground fault is temporarily recovered.

Further, although it is applicable to the case where the earth fault is not temporary but permanent, the method of locating the fault by re-pressurization has a possibility of developing a secondary disaster by the pressurization. There are drawbacks.

Despite these drawbacks, the currently installed single-phase high-voltage distribution line fault locating device has the advantage of being able to locate a ground fault. It has been put to practical use as a ground fault locator.

As seen in (Japanese Patent Publication No. 57-11023), when a high voltage distribution line using a coated electric wire has a disconnection failure,
The extension of the wire from the disconnection point to the end and the change in the leakage resistance are detected from the change in the voltage and current of another power supply other than the commercial frequency that is applied to the target distribution line in advance. A high-voltage distribution line disconnection failure point locating method has been announced that detects the occurrence of disconnection failure and determines the length of disconnection from the terminal from changes in phase voltage and zero-phase current.

This system requires a separate power source other than the commercial frequency, and has the drawback that the accuracy of wire location determination decreases as the wire disconnection point approaches the distribution end.

[0020]

The problem to be solved is that it is impossible to detect a wire breakage fault, a fine ground fault fault, or a high resistance ground fault fault.

Another feature is that, when a failure occurs, the data observed at both ends is converted into the same time data without the need for a synchronization device such as a dedicated constant synchronization circuit for always synchronizing the observation data.

Further, it is impossible to locate a short-circuit fault and a disconnection fault.

[0023]

According to the present invention, in order to detect a disconnection fault, a fine ground fault, and a high resistance ground fault, computers are installed at both ends of a power distribution terminal and a power distribution terminal, and the power distribution status is calculated by the computer. The main feature is to detect disconnection faults, micro-ground faults, and high-resistance ground faults by constantly monitoring the information in (1), capturing and storing it as monitoring data, and analyzing the stored data. .

For the purpose of detecting the disconnection fault, the fine ground fault fault, and the high resistance ground fault fault, by installing a device for monitoring the fault at both ends, the existing equipment relays actually installed are affected. It happened without a problem. Although the description here refers to both ends of the distribution, if multiple computers are installed between the beginning and end of the distribution, the beginning side is the distribution end, and its immediate vicinity is the distribution end. It means that, except for the beginning end and the final end, the placement computer is a distribution end computer and also a distribution end computer.

In the present invention, in the event of a failure, it is necessary to convert the data observed at both ends into the same time data, but it is possible to synchronize the observation data without the need for a synchronization device such as a dedicated constant synchronization line. The main feature is to do. The purpose of synchronization is to simply start / stop monitoring
It was realized without impairing the synchronization accuracy.

As a failure synchronization method, monitoring start /
The use of the stop line has been described here, but since the high-voltage line can also be used as a start / stop trigger, it should be understood as the meaning of communication means capable of start / stop trigger communication.

The main feature of the present invention is to identify a disconnection fault and a short-circuit fault from the constant monitoring data without performing repressurization that may cause a secondary disaster after a fault. The purpose of fault location is to constantly monitor the power distribution status, classify the monitoring data into normal status and failure status data, and analyze that data, but there is a security problem because the required location accuracy is not within the range. It was realized without repressurization.

[0028]

Operation: A computer having a system configuration having the functions shown in FIG. 1 is arranged at both ends of the power distribution line, and both computers arranged at both ends of the power distribution line collect power distribution information. The distribution information at the distribution end is the ground voltages V _R , V _T , the steady load phase currents I _R , I _T and the short-circuit currents I _SR , I _ST , the zero-phase voltage V _O , and the distribution information at the distribution end is the ground voltage V _r , When V _t , the steady load phase currents I _r and I _t, and the short-circuit phase currents I _sr and I _st , and the zero-phase voltage V ₀₀ , if the distribution end is an open end, the steady load phase currents I _r and I _{t become} The short circuit currents I _sr and I _st are both zero.

[0029]

[Equation 1]

Hereinafter, this symbol and this example will be described with the distribution terminal as an open end.

Any one of the monitoring computers according to claim 1 is set and set as a main computer and a slave computer,
Prior to performing constant monitoring, the main computer issues a monitoring command standby command to the slave computer, and prepares itself for monitoring standby. After a certain period of time when it is assumed that both main computers are ready for monitoring, the main computer will also give a constant monitoring start command to itself and constantly monitor the slave computer through the continuous monitoring start / stop line. Give a start command.

Under the instruction and the algorithm, both the main computer and the slave computer operate a counter algorithm that updates the counter every time a fixed point with a voltage waveform of the distribution line that is constantly monitored passes, and starts counting the counter. To do.

After that, when it is determined that the monitoring computer at any one of the power distribution terminal and the power distribution terminal in claim 1 has a failure, both of them are instructed to the counterpart computer via the stop trigger line to stop the continuous monitoring. And connect it to the interrupt input line in advance so that the command will interrupt the computer, and then stop the computer.

After the constant monitoring is stopped by the stop command, the main computer informs the slave computer of the counter information counted after the monitoring, and the data before and after the failure is calculated from the data recorded by the computer under the information. Both computers use the method of synchronous cooperation algorithm to find out the failure data.

When any one of the computers is determined to be in failure, the data of 30 waveforms constantly recorded in the endless file contains both normal data and failure data per data. From the normal state waveform and the fault state waveform data, the counter value that was determined to be a fault by itself,
Alternatively, the failure counter value notified from the other party is set as the failure occurrence time, and the time is set as the zero point of the time axis, and the negative time is classified as the normal waveform data and the positive time as the failure data. The positive and negative clearances from the time zero point are set in advance from the data collected by the artificial failure test, and the waveform of the negative set clearance position is selected as the normal waveform and the waveform of the positive set clearance position is selected as the failed waveform.

Here, the storage capacity for 30 waveforms is used, but if the storage capacity is insufficient or short, it may be reduced or increased. Therefore, this example will be described below. The waveform selected by the above method is subjected to Fourier integration to obtain the spectrum of the required order. Here, the fundamental wave is used, but the fundamental wave is not fixed. As the fundamental wave component, the voltage at the distribution end to ground V
_R [V], V _T [V], steady load phase current I _R [A], I _T
[A], short-circuit phase current I _SR [A], I _ST [A], zero-phase voltage V _O [V], distribution terminal ground voltage V _r [V], V
_t [V], the zero-phase voltage V ₀₀ [V] are processed, and the values will be discussed below.

In addition, when N is added to the leftmost end of each Suffux symbol, it represents a normal waveform value, and when it does not exist, it represents a fault waveform value. A short symbol is an S symbol, a ground fault is a G symbol, and a disconnection is a B symbol. Will be shown.

The symbols are defined as follows, and the symbols will be explained. The line voltage of the single-phase high-voltage distribution line V (= V _R + V
_T) [V], the power distribution side zero-phase voltage V _O (= V _R -V _T)
[V], terminal side zero-phase voltage V ₀₀ (= V _r −V _t ) [V],
Impedance Z [Ω] viewed from the distribution end, distribution side R-phase line impedance Z _LR [Ω], distribution side T-phase line impedance Z _LT [Ω], distribution side line impedance Z
_RT [Ω], impedance on receiving side line Z _rt [Ω], impedance between all distribution side lines Z _RTrt [Ω],

[0039]

[Equation 2]

Short-circuit Impedance Z _PS [Ω], ground leakage R phase distribution side admittance Y _RE [Ω], ground leakage T phase distribution side admittance Y _TE [Ω], ground leakage R phase power reception side admittance Y _rE [Ω] ], Ground leakage T phase power receiving side admittance Y _tE [Ω] All ground leakage R phase power distribution side admittance Y _RrE [Ω],

[0041]

[Equation 3]

Total ground leakage T-phase distribution side admittance Y
_TtE [Ω],

[0043]

[Equation 4]

Total ground leakage R phase T phase line-to-line distribution side admittance Y _E [Ω] is

[0045]

[Equation 5]

Impedus Z as seen from the power distribution end during normal operation
[Ω] is the line impedance Z _NPS

[0047]

[Equation 6]

When,

[0049]

[Equation 7]

It can be expressed as From the above, each failure detection method can be expressed as follows. (A) The short-circuit detecting shorting, Z _PS «Z the _NPS conditions, because the line impedance between Z _NPS is to join a short circuit impedance scan Z _PS, is the line impedance Z _PS, and the power distribution end at short The impedance Z seen from

[0051]

[Equation 8]

As a result of Z << Z _N , the normal current I _NR becomes the fault current I _R , which increases and exceeds the preset current value, so that I _R >> I _NR can be detected by the computer at the power distribution end. (B) Ground fault detection (R phase accident notation, T phase is suffix R
In the R-phase ground fault, V _R << V _NR and the line voltage V hardly changes.

[0053]

[Equation 9]

Is increased and can be detected by V _O >> V _NO . (C) Disconnection detection (R phase accident notation, T phase is suffix R
Replace the symbol with T.) For disconnection near distribution, Y _RE << Y
As a result of becoming _TtE , the monitoring computer at the distribution end

[0055]

[Equation 10]

It can be detected by _{Discontinuity of the} distribution end is Y _rE
≪As a result of becoming Y _Tt ,

[0057]

[Equation 11]

According to the above, the computer at the power distribution terminal can detect it, and both the computer at the power distribution terminal and the computer at the power distribution terminal are constantly monitoring for the accidents (b) and (c), so that V _O and V respectively. _{Since OO} can be detected, both ground fault and disconnection can be detected. The above is summarized and the flow of failure detection is shown in FIG.

The orientation calculation formula for short circuit, ground fault, and disconnection of the high-voltage distribution line is such that when the ground capacitance is C _E , the value is R phase,
Considering that both T phases are equal, the ground admittance is

[0060]

[Equation 12]

Because it can be expressed as in [0061], the Y _NE
Since it can be obtained in advance from a line constant test and a theoretical calculation formula, Y _NE will be considered to be known and explained below. (A) The short orientation shorted, Z _PS «Z the _NPS conditions, because the line impedance between Z _NPS is to join a short circuit impedance scan Z _PS, is the line impedance Z _PS, and the power distribution end at short The impedance Z seen from

[0062]

[Equation 13]

Assuming that the impedance at the short-circuit point is Z _RT ≈0, Z _PS will be Z _PS ≈0.

[0064]

[Equation 14]

[0065]

[Equation 15]

Therefore, if the terminal short circuit current value I _RL is measured in advance,

[0067]

[Equation 16]

Therefore, Z _L is

[0069]

[Equation 17]

Thus, the line impedance Z _L can be obtained, and from the short circuit current I _R at the time of short circuit failure,

[0071]

[Equation 18]

According to

[0073]

[Formula 19]

Since the short-circuit impedance Z is obtained from the above, the reactance fault reference value is

[0075]

[Equation 20]

Can be obtained as (B) Wire disconnection orientation Hereinafter, it will be described as an R-phase accident, but in the case of a T-phase accident, it can be obtained by replacing the suffix R symbol with T. When the overhead line and the cable are mixed, the capacitance to ground is not linear, and the orientation accuracy is not stable because the capacitance ratio between the cable portion and the overhead portion is significantly different.

Therefore, the load along the JR line is light, but about 1 / km of 1 to 3 kVA transformers are installed and the signal load is the same. Therefore, paying attention to this exciting power and load, Was decided to be incorporated into the orientation method. Therefore, the normal distribution power is

[0078]

[Equation 21]

In the case of abnormal power distribution power,

[0080]

[Equation 22]

Can be obtained as From the above, the fault location is

[0082]

[Equation 23]

It can be expressed as Or

[0084]

[Equation 24]

However,

[0086]

[Equation 25]

[0087]

[Equation 26]

Can be obtained as

[0089]

1 is a system configuration diagram of an embodiment of the present invention.

To prepare for the start of measurement, the computer 4m in FIG. 1 notifies the partner computer 4s of the preparation for the measurement state through the line 6. After an appropriate time has passed, it is determined that the preparation for measurement is complete, and a 4m computer issues a measurement start command to its own 4m computer and the other computer 4s through line 7.
Start measurement for both m and 5m.

When the measurement is started, since the current is also converted into a voltage signal, all the information is a voltage signal, and the voltage is insulated by electro-optical conversion, photoelectric conversion, and is amplified through an appropriate filter. After 1m (1s), sample folder 2m (2s), analog digital converter 3-
1m (3-1s), 3-2m (3-2s) to 4m (4
s) Waveform values are loaded into the main computer.

However, the inside of the parentheses indicates the slave computer side. Since the taken-in voltage waveform value changes by alternating current, the count is updated upon the passage of the specific point (here, the zero point, but an appropriately determined point).
In other words, as part of the preparation for measurement, the zero-cleared counter memory on the memory of the computer starts measuring the number of times the zero-cross point has passed.

On the other hand, the waveform V ₀ (power distribution side), V
_It is calculated whether ₀₀ (power distribution side) and I _R (power distribution side) exceed predetermined values, and the presence or absence of abnormality is checked for each wave.

When the 4m computer determines that there is an abnormality, it issues a measurement stop command to the partner computer 4s through the line 7 to the partner computer 4s. In addition, when it is determined by the computer for 4s that it is abnormal,
The partner computer 4s issues a measurement stop command to the partner computer 4m through the line 7. Then, from the computer of 4m, the fault counter value is known to the computer of 4s through the line of 6.

In addition to the case where abnormalities are detected at the same time and their counters match, when only one of them is detected,
If the value is different from the accident counter value, the counter value of the computer of 4m is used. As described above, the synchronization between computers can be matched. Therefore, since it is not necessary to always send the synchronization information from the master clock station to the slave clock through the synchronization line, failure synchronization can be achieved without the need for a transmission / reception device for that purpose.

The voltage waveform and current waveform are subjected to Fourier series expansion, the fundamental wave component is extracted and the orientation calculation is started, with the normal waveform before the three waveforms of the accident counter value and the fault waveform after the two waveforms. After the orientation calculation, the failure information is displayed on the terminals 8 in various places.
As described above, since the monitoring data is always stored and stored as an endless memory, the stored data can be classified into failure information and normal information.Therefore, it is necessary to re-pressurize the data for orientation in order to perform orientation. Therefore, there is no need for a safe and repressurizing device.

Further, it is not necessary to separately provide a power source for disconnection in the high voltage distribution line.

[0098]

As described above, the disconnection failure of the present invention,
Detects minor ground faults, high-resistance ground faults, and always synchronizes observation data The advantage of converting the data observed at both ends at the same time when there is no need for a synchronization device such as a dedicated continuous synchronization line There is. Short circuit failure, disconnection failure
Since the processing is performed by a computer algorithm, there is an advantage that it can be handled accurately and quickly, and when the accuracy can be improved, the program can be changed successfully and the processing can be appropriately performed.

The above method can also be applied to a three-phase high-voltage distribution line by incorporating a data synchronization method into the three-phase high-voltage distribution line.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of a system configuration of a monitoring computer arranged at a power distribution end and a power distribution end.

FIG. 2 is an example of a conventional system that does not use the present invention, in which a capacitor is arranged at the end of a distribution line, an unbalanced voltage is captured, and a ground return transmission system is used to notify the disconnection protection device to the distribution side. It is a figure.

[Fig. 3] Fig. 3 is an example of a conventional system not using the present invention, which is a ground return transmission system in which a terminal device that operates at the same time as a disconnection accident is placed at the end of a section of a timed automatic division switch and a disconnection detection relay is installed at a substation. , Generate a pulsed disconnection signal,
It is explanatory drawing about the disconnection protection apparatus which notifies disconnection information to a power distribution side.

FIG. 4 is an example of a conventional method not using the present invention, in which a short-circuit current and a zero-phase current or a zero-phase voltage occur at the same time, and the short-circuit current continues until the arc following the fusing line is extinguished.
It is explanatory drawing about the disconnection detection apparatus which prepares the overcurrent element and the ground fault current element which have the characteristic which suits the negotiating characteristic, and determines with the simultaneous operation logic of both to be a disconnection.

FIG. 5 is an explanatory diagram of an apparatus for locating a ground fault point according to the principle of the Murray loop method by repressurizing in an example of a conventional method not using the present invention.

FIG. 6 is a flowchart of failure detection according to the present invention.

[Explanation of symbols]

1m, 1s electrical / optical conversion, optical / electrical conversion,
Signal amplification amplifier 2m, 2s sample folder 3-1m, 3-1s analog digital converter 1 3-2m, 3-2s analog digital converter 1 4m, 4s monitoring computer 5m, 5s communication device 6 telephone line 7 monitoring Start / stop line 8 Display terminal 9 Disconnection detection: Disconnection detection device 10 Disconnection display device 11 Signal tuning device 12 Disconnection detector 13 Circuit breaker 14 Main transformer 15 Automatic classification switch 16 Terminal device 17 Disconnection detection relay 18 CT 19 ZCT 20 GPT 21 Zero-phase current element 22 Overcurrent element 23 Lightning burnout determination mechanism 24 Disconnector

Claims (4)

[Claims] 1. A single-phase high-voltage power distribution line (non-grounded system) supplied with power and supplied with power via an insulating transformer for insulating the power supply system at a high-voltage power receiving point, at both ends of the power distribution end and the power distribution end. , A monitoring computer that constantly monitors the distribution status of the distribution line, analyzes the distribution failure data that occurred on the distribution line with these monitoring computers, and reports the information to the required location by telephone. A single-phase high-voltage distribution line fault detection / orientation device. 2. A fault detection algorithm for determining the presence or absence of a short circuit, a ground fault, or a disconnection fault according to claim 1, is incorporated in a computer for monitoring both ends of a distribution end and a distribution end, and both ends are arranged by the algorithm. A single-phase high-voltage distribution line fault detection / orientation device, which has the function of independently detecting a fault. 3. The monitoring computer according to claim 1,
One of the main computer and a plurality of slave computers are arranged, and the main computer issues a monitoring command standby command to the slave computer before performing constant monitoring, and prepares itself for monitoring standby.
After a certain period of time, when both sides are supposed to be ready for monitoring, the main computer gives itself an always-monitoring start command, and through the always-monitoring start / stop line,
It gives a constant monitoring start command to the slave computer and, under the command and its algorithm, both the main computer and the slave computer update the counter every time a fixed point with a voltage waveform of the distribution line that is constantly monitored passes. Activate the counter algorithm and start the counter counting. After that, when it is determined that the monitoring computer at any one of the power distribution end and the power distribution end in claim 1 has a failure, both of them issue an order to stop the continuous monitoring via the stop trigger line. After constant monitoring stop,
The main computer informs the slave computer of the counter information counted after monitoring, and the monitoring computer is equipped with a synchronization cooperation algorithm that is a method of calculating the data before and after the failure from the data recorded by the slave computer under the information. A single-phase high-voltage distribution line fault detection / orientation device. 4. The computer according to any one of claims 1, 2, and 3, which judges that a failure has occurred and issues a monitoring stop command by itself, or receives a monitoring stop command from the other party, after which the computer always stops monitoring by the monitoring stop command. The data synchronized by the slave computer by the synchronization method according to claim 3 is transmitted to the main computer, and a fault localization algorithm for locating a fault location is incorporated from the transmitted data and the fault data of itself. The main computer locates the point of failure, and detects single-phase high-voltage distribution line failure.
Orientation device.