JPH07270482A - Fault point coating device - Google Patents

Abstract

PURPOSE:To accurately collate the data of all terminals at an identical time and provide a highly accurate result by causing a terminal device to transmit a sampling address, and synchronizing sampling addresses between a central judgement device and the terminal device. CONSTITUTION:In a normal case free from a system accident, data transmission is carried out between a central judgement device and a terminal device, thereby maintaining a synchronized sampling process. When an accident occurs, the central judgement device and each terminal device detect the accident through an accident detection means 22, and a data freezing means 25 is made to store data for locating operation. Furthermore, a control means 24 causes each terminal device to transmit voltage and current data stored in the central judgement device, regarding the occurrence of an accident. On the other hand, the central judgement device performs the locating arithmetic operation, when the data of all terminals become available. Also, sampling phase difference operation for synchronizing a sampling process in a normal case and locating operation upon occurrence of an accident are carried out by use of all terminal data. In either case of the calculation, data sampled at an identical time are collated with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fault point locating device for locating a fault point by collecting voltage and current at each terminal of a transmission line.

[0002]

2. Description of the Related Art Conventionally, there are a surge receiving method, a pulse radar measuring method, an impedance measuring method and the like as a fault point locating method for a transmission line. The former two require expensive communication devices and the like. On the other hand, the latter impedance measurement method uses the voltage and current obtained from the transformer and current transformer to perform the orientation, and does not require new equipment to obtain the input amount. However, when there is a failure point resistance, not only the current of its own terminal but also the other terminal flows into the failure point, so that the current phase angles of the two do not necessarily have the same phase, which may cause a ranging error.

For this reason, the impedance measuring method of locating only the voltage and current of its own terminal, when applied to a multi-branch transmission line having a branch in the middle, is disclosed in, for example, Japanese Patent Application No. 62-246186. A correction method for the effect of various branches has been proposed. However, these methods do not eliminate the influence of branching in principle, and it is not possible to judge whether the fault point is on the main line side or the branch line side for the fault beyond the branch point.

Under such circumstances, a method of taking in the voltages and currents of all terminals of the power transmission line and using the Kirchhoff's law to perform the orientation without being affected by the resistance at the fault point is drawing attention. In the impedance measurement method in which the voltage and current of all terminals are located, the failure point can be accurately identified in principle even if there are branches, and the effect of the resistance at the failure point can be completely eliminated. Is desired as a method to be applied to.

[0005]

In the impedance measuring method in which the voltage and current of all terminals are used for orientation, it is necessary to literally collect the voltage and current information of all terminals in one place before performing the orientation calculation. Therefore, a transmission means for transmitting the voltage / current information is required. Furthermore, the voltage and current data of all these terminals must be synchronized. However, high-speed transmission lines such as microwave lines are not always prepared in transmission line systems with many voltage branches and low voltage classes. Therefore, for example, Japanese Patent Laid-Open No. 3-282377 (hereinafter referred to as the prior art) has been proposed as a method capable of achieving sampling synchronization even in a low-speed transmission line.

In this method, the phase difference of the voltage at the branch point viewed from each terminal is calculated, and the sampling signal on the terminal device side is shift-controlled by the amount of this phase difference to establish synchronization (SP synchronization). .

However, when the low-speed transmission line is used, this transmission delay time fluctuates, and since this fluctuation is larger than the sampling time interval, it is not always true that the synchronous control (SP synchronous control) can be carried out accurately. Not necessarily. For this reason, when matching the data at the same time point between the terminals, a deviation occurs in the sampling unit, and the control amount becomes large during the sampling synchronization control, so that stable control cannot be performed. Alternatively, there is a problem in that, in the orientation calculation performed when a system fault occurs, the data at the same time point of each terminal cannot be matched, and the orientation accuracy may be deteriorated.

The present invention has been made to solve the above problems, and is a case where the present invention is applied to a low speed transmission line in an impedance measuring type fault point locating device for locating based on voltage and current information of all terminals. Even when performing sampling phase difference calculation or orientation calculation for sampling synchronization control, it is possible to accurately match the data of all terminals at the same time point, and to provide a fault point locating device that can obtain accurate results. Has an aim.

[0009]

A fault point locating device according to claim 1 of the present invention collects the voltage and current of each terminal of a multi-terminal transmission line in a central judgment device and locates the fault point from these electric quantities. In the fault point locating device, the SA synchronization control means for transmitting the sampling address from the terminal device and synchronizing the sampling address between the central determination device and the terminal device, and the central determination device and the terminal device synchronized by the SA synchronization control means. The SA coincidence control means for detecting the SA shift that minimizes the electric quantity of the specific sampling address and SA correction, and the phase difference calculated from the electric quantity of each terminal device after executing the SA coincidence control means are zero. To achieve this, SP synchronization control means for synchronizing the sampling times between the central determination device and the terminal device, the SA synchronization control means, the SA coincidence control means, and the SP It was composed of a locating calculation means for locating the fault point from the electric quantity of each terminal controlled synchronously by the period control means.

The fault point locating device according to claim 2 of the present invention is the fault point locating device according to claim 1, wherein
The A correction is made for the electric quantity of each terminal collected when the accident occurs.

A fault point locating device according to a third aspect of the present invention is the fault point locating device according to the first aspect, wherein the S coincidence control means performs
The A correction signal is transmitted to the terminal device, and the terminal device side corrects the sampling address.

[0012]

The fault point locating device according to claim 1, claim 2, and claim 3 of the present invention performs sampling by performing data transmission between the central determination device and the terminal device during normal times when no system fault has occurred. In sync. When an accident occurs, both the central judgment device and each terminal device detect the accident, and the data freezing means stores the data for orientation calculation. Each terminal device transmits the voltage and current data at the time of the accident stored in the central judgment device by the transmission control means, and the central judgment device carries out the orientation calculation when the data for all terminals are gathered. The sampling phase difference calculation during normal sampling synchronization and the orientation calculation when an accident occurs are performed using the data of all terminals, but in both cases, it is necessary to match the data sampled at the same point in time. . Therefore, before performing these calculations, the SA shift width between the data of each terminal is detected, and the phase is shifted by the amount of this shift width, and the phase is corrected before the calculation is performed. It is possible to eliminate the influence of the generated phase shift between the terminal data.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a system configuration diagram of an embodiment in which the fault point locating device of the present invention is applied to a power system, and a four-terminal system will be described as an example. In FIG. 1, 121, 131, 141
Is a terminal device provided at each terminal, and each terminal device has a data creation unit 123, 133, 143 and a transmission unit (CCU) 124, 134.
, 144. Reference numeral 201 denotes a central determination device provided at a representative terminal (Ass), which performs a location calculation of a failure point using voltage and current data transmitted from each terminal. The transmission units 124, 134, 144 and the central determination device 201 are connected by low-speed transmission lines 125, 135, 145.

The devices of the terminals A, B, C and D in the figure are normally sampling-synchronized. On the other hand, when an accident occurs, an accident is detected by the accident detection means provided in each of the central judgment device and the terminal device, and the data for orientation calculation is frozen (stored) individually at each terminal. Each terminal device transmits the frozen data to the central determination device, and when the data of all terminals are gathered in the central determination device, the orientation calculation means determines the distance to the accident point.

FIG. 2 is another system configuration diagram. In this system, the central determination device 201 is independently provided in addition to the representative terminal, and it is obvious that the same function can be obtained by this configuration. Here, the sampling synchronization, which is the main point of the present invention, will be described. First, a phase difference calculation in sampling synchronization will be described as an example with reference to the drawings.

In FIG. 3, Ass, Bss, and Css are used as terminals 3
The transmission line system diagram of the terminal is shown, and its branch point is J point.
A central determination device is installed in Ass, and a terminal device is installed in Bss and Css, respectively. Further, VAj and VBj are voltages at the branch point J viewed from Ass and Bss, respectively. Sampling synchronization control (SP
(Synchronous control) is performed by calculating the phase difference between VAj and VBj and shifting-controlling the sampling signal on the terminal device side by the amount of this phase difference.

Here, in order to obtain the accurate phase difference of the sampling signal between the central judgment device and the terminal device, the voltages and currents of the central judgment device and the terminal device for calculating the voltages VAj and VBj at the branch point J. Both data must be sampled at approximately the same time. In order to ensure this simultaneity, sampling address synchronization control (SA synchronization control) is performed prior to the calculation of the phase difference between VAj and VBj. FIG. 4 shows a control for numbering (sampling address SA) in the order of sampling and for adjusting this SA between all terminals (SA synchronous control). This control is for transmitting / receiving data between the central determination device and the terminal device. Implement by doing. SA1 indicates the value of SA when data is first transmitted from the terminal device to the central determination device.

SA2 indicates the value of SA of the central judging device when the data from this terminal device is received. The central determination device transmits data to the terminal device after t sampling (fixed time) after receiving the data at SA2. At this time, the value of SA2 is included in the transmission data and transmitted. When the terminal device receives the data from the central determination device, the transmission delay time ΔT can be calculated by the equation (1) by measuring the time T from the time of SA1 to the data reception.

[Equation 1]

Further, the S transmitted from the central judgment device
By using the value of A2, the deviation width ΔSA of the value of SA between the central determination device and the terminal device can be calculated by the equation (2).

[Formula 2] ΔSA = SA1− (SA2−ΔT) ………… (2) SA between terminal devices by the amount of ΔSA calculated by the formula (2).
By correcting the value of, the value of SA can be synchronized in principle between the central determination device and the terminal device.

The above procedure is called SA synchronization control. However, when a low-speed transmission line is used, the transmission delay time Δ
Even if the value of T varies and the SA synchronization control is performed based on the equations (1) and (2), it is not always possible to make the central determination device and the SA of the terminal device truly coincide with each other. For example, the waveforms of the branch point voltages Vaj and VBj viewed from Ass and Bss after SA synchronization control are in a state where their phases are deviated from each other by one sampling interval or more, as shown in FIG. Originally, since the voltages at the same point are seen from Ass and Bss, if they are perfectly synchronized, the waveforms of VAj and VBj should be completely the same.

Here, control for matching SA is performed by the following means. In Figure 5, SA of VAj
, M-1, m, m + 1, ..., and the SA sequence of VBj is ..., n-1, n, n + 1 ,. For example, VAj
Sampling data when SA = m is expressed as VAjm. Since the reference for synchronization is considered to be the central judgment device, the data of VAjm of the central judgment device is considered as the reference data and the calculation shown in the equation (3) is performed.

## EQU00003 ## Pk = VAjm.VBjk sin .theta .... (3) k = ..., n-1, n, n + 1 ,. According to equation (4), the true S between the central judgment device and the terminal device
The deviation value ΔSA ′ of A can be obtained. The SA of the terminal device is equal to the value of ΔSA ′ calculated in this way.
If the control is performed so as to correct, the synchronization state between the central determination device and the terminal device can be kept within one sampling interval (this control is abbreviated as SA coincidence control hereinafter).

[Formula 4] ΔSA ′ = m−k ′ …………… (4)

If the sampling phase difference calculation is performed and the sampling synchronization control is performed after the SA coincidence control is completed, the control amount for the sampling signal can be minimized (below the sampling synchronization), so that stable synchronization control can be performed. I can. Also, in this way,
If the SAs are matched in advance between the terminal devices, the amount of voltage and current data transmitted from the terminal device to the central decision unit during the sampling phase difference calculation or the orientation calculation in the event of an accident can be reduced. It is also possible to improve the transmission efficiency.

Next, the configuration and content processing of the central determination device and the terminal device based on the content of SA match control will be described with reference to the drawings. FIG. 6 is a functional block diagram of the central determination device in one embodiment. In FIG. 6, 20 is an input processing means for introducing the current I and voltage V of its own end, 21 is a receiving means for obtaining the current and voltage data from each terminal device A, B, C, 22
Is an accident detection means for detecting the occurrence of an accident from each of the input data from its own end, and 23 is a synchronization adjustment signal generation for generating a sampling synchronization adjustment signal from each input data from its own end and each reception input data from each terminal. It is a means. Reference numeral 28 denotes SA coincidence control means for performing SA coincidence control from the input data of its own terminal and each terminal.

Further, 24 is a transmission control means for obtaining each input data from the terminal device, 25 is a data freezing means for freezing (storing) each input data at the time of an accident, and 26 is for each terminal device. A transmitting means for transmitting a signal, and 27 is an locating means for performing an locating operation based on the received data from the own terminal and each terminal device.

FIG. 7 is a flow chart showing the processing contents of the central judgment device shown in FIG. Input processing means 20 in normal times
Based on the self-end current and voltage data from the terminal device and the current and voltage data of the terminal device obtained from the transmission control means 24 via the reception means 21, the SA coincidence control means 28 performs central judgment based on the above equations (3) and (4). SA deviation width ΔS between the device and each terminal device
A'is calculated (steps S70, S71). The reason for this is that, as described above, when a low-speed transmission line is used, the transmission delay time varies, and this variation is adjusted in advance within at least one cycle.
Based on the ΔSA ′ data from the SA coincidence control means 28, SA is corrected for the voltage and current data of the terminal device (step S72).

At the same time, the synchronization adjustment signal generating means 23
Then, a sampling synchronization adjustment signal is generated based on the self-end voltage and current data from the input processing means 20 and the voltage and current data on the side of each terminal device obtained from the transmission control means 24 via the receiving means 21. That is, the SA is corrected to bring the input data within about one cycle, and then the phase is adjusted (sampling phase difference calculation) by the sampling synchronization adjustment signal to sufficiently reduce the phase difference (step S73). .

The sampling synchronization adjustment signal thus obtained is transmitted from the transmission means 26 to the terminal device via the transmission control means 24 (step S74). Further, in parallel with this procedure, the accident detection processing means 22 determines whether or not a system accident has occurred from the current and voltage data obtained from the input processing means 20, and if there is an accident, the data freezing means 25 is orientated and activated. A signal is output (step S75). The data freezing means 25 freezes (stores) the own-end current and voltage data for orientation calculation, and passes it to the orientation means 27. The locating means 27 performs the locating operation if the data of all terminals including its own terminal are prepared (step S76). At this time, the data of ΔSA 'from the SA coincidence controlling means 28 is also applied to the voltage and current data of the terminal device. It is assumed that the SA is corrected based on the above (steps S77 and S78).

FIG. 8 is a functional block diagram of the terminal device.
In FIG. 8, 10 is an input processing means for obtaining the voltage and current data of its own end, 11 is a receiving means for inputting a sampling synchronization adjustment signal from the central judgment device, 12 is a system based on the current and voltage data obtained from the input processing means. Accident detection means for detecting the occurrence of an accident, 13 is a data synchronization means for performing sampling synchronization control based on the received sampling synchronization adjustment signal,
Reference numeral 14 is a transmission control means, 15 is a data freezing means, and 16 is a transmission means.

FIG. 9 is a flowchart showing the processing contents of the terminal device shown in FIG. In normal times, the data synchronization means 13 passes the voltage and current data obtained from the input processing means 10 to the transmission control means 14 as data for synchronization control calculation, and transmits it to the central determination device via the transmission means 16. On the other hand, the transmission control means 14 reads the sampling synchronization adjustment signal transmitted from the central determination device from the reception means 11 and passes it to the data synchronization means 13. In this case, the correction value of SA is also passed (step S90).

The data synchronizing means 13 controls the sampling synchronization of the input processing means 10 based on the sampling synchronization adjusting signal (step S91). At the same time as this procedure, the accident detection processing means 12 determines whether or not a system accident has occurred from the current and voltage data obtained from the input processing means 10.
When an accident occurs, a start signal is output to the data freezing means 15. The data freezing means 15 freezes the orientation data to be transmitted to the central judgment device, and the transmission control means 14 via the transmission means 16 transmits the frozen data to the central judgment device (step S93).

In the case of the above embodiment, the central judgment device side
The amount of deviation ΔS of SA from the terminal device according to equations (3) and (4)
A'is calculated, and the voltage and current data transmitted from the terminal device at the time of the sampling phase difference calculation or the orientation calculation is directly corrected by using these values to perform the calculation. .

FIG. 10 is a functional block diagram of the central judgment device in the second embodiment. 10, parts that are the same as those shown in FIG. 6 are given the same reference numerals, and descriptions thereof will be omitted. The difference from the above-mentioned embodiment (FIG. 6) is that the SA coincidence control means 28 calculates the value of ΔSA ′ using the voltage and current data of the central judgment unit, and then the transmission control means 24 calculates the value of ΔSA ′. The point is that the data is transmitted from the transmission means 26 to the terminal device via the terminal, and the terminal device that receives the signal actually corrects SA by ΔSA '. Other configurations are the same as those in FIG.

FIG. 11 is a functional block diagram of the terminal device in the second embodiment. 11, the same parts as those in FIG. 8 are designated by the same reference numerals and the description thereof will be omitted. When the SA correction value ΔSA ′ is received from the central determination device via the receiving means 11 and the transmission control means 14, the SA coincidence control means 18 directly executes the SA correction control on the input processing means 10. The other parts are the same as in the above-described embodiment (FIG. 8). In this way, once the SA coincidence control is carried out on the terminal device side, the voltage and current data transmitted from the terminal device to the central judgment device thereafter is SA synchronized with the central judgment device. In the central judgment device, it is not necessary to perform the correction of SA again in the calculation of the sampling phase difference when performing the sampling synchronization and the calculation of the orientation when the accident occurs.

According to the present embodiment, since the SA is synchronized between the central determination device and the terminal device,
Since there is no shift in SA of the voltage and current data transmitted from the terminal device to the central determination device with respect to the central determination device, the amount of data to be transmitted can be reduced and the transmission efficiency of the system can be improved. Furthermore, when the sampling synchronization control is completed, it is possible to create a sampling signal that is perfectly synchronized between the central determination device and the terminal device.Therefore, by creating a reference signal for the tester based on this signal, It also becomes possible to carry out end-to-side accident simulation tests.

[0035]

As described above, according to the present invention, even in the system using the low-speed transmission line, the sampling synchronization correction is performed after the correction value by the SA is once obtained. It is possible to provide a fault point locator capable of perfectly synchronizing the SA by performing the calculations of the formulas (3) and (4), and thus performing stable sampling synchronization control and accurate locating calculation. The present invention is highly effective in the case of a system using a low speed transmission line, and it is obvious that the present invention can be applied to a system using a high speed transmission line.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an embodiment of a fault point locating device according to the present invention.

FIG. 2 is a system configuration diagram of another embodiment.

FIG. 3 is an explanatory diagram of a sampling synchronization method.

FIG. 4 is an explanatory diagram of SA synchronization control.

FIG. 5 is an explanatory diagram of SA matching control.

FIG. 6 is a functional block diagram of an embodiment of a central determination device according to the present invention.

FIG. 7 is a flowchart illustrating the processing content of the central determination device.

FIG. 8 is a functional block diagram of an embodiment of a terminal device according to the present invention.

FIG. 9 is a flowchart illustrating the processing content of the terminal device.

FIG. 10 is a functional block diagram of a second embodiment of the central determination device according to the present invention.

FIG. 11 is a functional block diagram of a second embodiment of the terminal device according to the present invention.

[Explanation of symbols]

 10, 20 Input processing means 11, 21 Reception means 12, 22 Accident detection means 13 Data synchronization means 14, 24 Transmission control means 15, 25 Data freezing means 16, 26 Transmission means 27 Orientation means 18, 28 SA coincidence control means 113, 121, 131, 141 Terminal device 201 Central judgment device

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Mitsuru Yamaura 1st in Toshiba Fuchu factory, Fuchu-shi, Tokyo (72) Inventor Akio Taketa 1st Toshiba-machi, Fuchu, Tokyo Tokyo Fuchu factory, Ltd.

Claims (3)

[Claims] 1. In a fault point locator for collecting voltage and current of each terminal of a multi-terminal transmission line in a central deciding device and locating a fault point from these electric quantities, a sampling address is transmitted from the terminal device to perform central deciding. SA synchronization control means for synchronizing sampling addresses between the device and the terminal device,
After the SA coincidence control means is executed, the SA coincidence control means for detecting the deviation of the SA that minimizes the electric quantity of the specific sampling address of the central determination device and the terminal device synchronized by the SA synchronization control means, and performing the SA correction is executed. SP for synchronizing the sampling time between the central determination device and the terminal device in order to make the phase difference calculated from the electric quantity of each of the terminal devices zero
A failure point comprising synchronization control means and orientation calculation means for locating the failure point from the electric quantities of the terminals synchronously controlled by the SA synchronization control means, SA coincidence control means and SP synchronization control means. Orientation device. 2. The fault point locating device according to claim 1, wherein the SA correction by the SA coincidence control means is performed on the electric quantities of the terminals collected at the time of the accident. 3. The fault point locating device according to claim 1, wherein an SA correction signal by the SA coincidence control means is transmitted to the terminal device, and the terminal device side corrects the sampling address.