JPH05142285A - Locating equipment of fault point - Google Patents

Abstract

PURPOSE:To locate highly precisely an accident point in a so-called 'appendix' terminal which is a branch terminal having no terminal device provided. CONSTITUTION:A terminal device 6 takes in data on a voltage and a current of each terminal from data input part 8 and transmits these data to a central determination device 13. The central determination device 13 takes in the data on the voltage and the current of its own end through a data input part 7 and determines whether an accident point is in the vicinity of a branch point or not, on the basis of the data of its own end and the received data. When it is determined that the point is in the vicinity of the branch point, the accident point is re-located by using a voltage at the branch point and a current flowing into the branch point.

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 an accident point at the time of an accident by using the electric quantities of the terminals of a multi-terminal transmission line.

[0002]

2. Description of the Related Art As a fault point locating method for obtaining the distance to a fault point using voltage and current in a two-terminal system, the impedance between the self-point and the fault point is obtained from the voltage and current at the self-end to determine the distance There is an impedance calculation type fault point locator for locating and a collection type fault point locator for locating the distance by using the condition that the remaining voltage at the fault point calculated from the voltage and current data of both terminals is equal.

First, a conventional distance type fault location device will be described with reference to the drawings. In FIG. 4, a distance type fault point locating device 20 is installed in the electric station 2, voltage and current data of its own end is input from the data input section 7, and the locating section 9 calculates the distance impedance to the fault point. Standardize. According to this method, in the system of FIG. 5, the self-end voltage is V _A , the pre-fault current is I _A , the fault current is I _A ′, the change current before and after the fault is I _A ″, and the fault voltage To V
_F , the fault point resistance is Z _F , the line impedance Z per unit length, and the distance 1 to the fault point are expressed by the equation (1). _{V F = V A -I A ·} Z · l ......... (1)

[0004] (1) for V _F is the unknown in the formula, there is a need to be erased. Therefore, since it can be assumed that the fault point resistance Z _F is a pure resistance component, if the fact that the current I _F flowing into the fault point and the fault point voltage V _F are in phase is used, I _m (V _F · I _F ^* ) = 0 ... (2) Note that I _F ^* is a conjugate complex number of I _F. Further, I _F = I _A −I _A ′ = I _A ″ ... (3) Substituting the formulas (1) and (3) into the formula (2), V _F is erased and I _m (V _A −I _{A · Z · l) · I} A "* = 0 Is asked. However, according to this orientation principle, in the three-terminal system of FIG. 6, it is impossible to determine whether the orientation result lkm of the distance type fault location device at the A end is an accident at F ₁ point or an accident at F ₂ point. There was a flaw.

Next, a conventional collecting type fault point locating device will be described. In FIG. 7, a terminal device 6 is installed at an electric station 3, voltage and current data is input from a data input unit 8, and a central determination device 5 is used by using a transmission line 12 from a transmission unit 11.
Transmit to. A central determination device 5 is installed in the electric station 2, inputs voltage and current data of its own end from a data input unit 7, and receives data of a terminal device 6 from a reception unit 10. Using these data, the orientation section 9 calculates the remaining voltage at the fault point and locates the fault point.

[0006] According to this, the fault point voltage V _F in system of FIG. 8, the voltage across (V _A, V _B), a current (I _A, I
_B ), the line impedance Z per unit length, the line length l, and the distance to the fault point l _x, which is expressed by equation (5). Becomes In the equation (6), since the accident point voltage V _F is theoretically erased, the influence of the accident point resistance is not received in principle. Therefore, if the quantity of electricity at both ends can be measured accurately, accurate orientation can be performed.

[0007]

However, in the case where there is a terminal where the terminal device cannot be installed, that is, the cecum terminal 4 due to the absence of CT or the absence of a transmission line as in the system of FIG. 9, (6) In the formula, if an accident occurs between the branch point and the cecal terminal, the orientation after the branch point becomes impossible. Below figure
This will be explained in 10. In Fig. 10, terminal B is a cecal terminal, so voltage and current data cannot be captured. When an accident occurs between J and B, the voltage and current data are only those at the A and C ends, so the voltage at the accident point is the voltage at both ends ( _VA ,
V _C), current (I _A, from I _C), the line impedance Z and line length l per unit length, the distance l _x to the fault point
It is expressed by equation (7). Equation (8) is the same as equation (6), and it becomes the same as the orientation result in the system of Fig. 8. That is, when an accident occurs at the so-called cecal terminal, a fault current equivalent to the fault current flows at the branch point, so that the branch point voltage V _J corresponds to the fault point voltage V _F.

Next, the function of the central judgment device of FIG. 9 will be described with reference to FIG. The self-end voltage / current input means 201 inputs the self-end voltage / current data, and the data storage means 202 stores the data. The voltage / current data receiving means 203 receives voltage / current data from the terminal device at the other terminal. The branch point voltage / current creating means 204 receives data from the data storage means 202 and the data receiving means 203, and creates the voltage and current at the branch point. Since the accident point locating means 205 locates according to the concept of Eq. (8), in the system of Fig. 10, if an accident occurs at the cecal terminal, the locating result will be erroneously located as the branch point. It was The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a failure point locating device that can highly accurately locate an accident at a so-called cecal terminal.

[0009]

In order to achieve the above object, the present invention provides a fault point locating device for locating a fault point by using the voltage and current of each terminal of a multi-terminal transmission line. A terminal unit including a data input unit for inputting current data and a transmitting unit for transmitting the taken-in voltage and current data, a receiving unit for receiving data transmitted from each terminal unit, and self-end voltage and current data A central determination device comprising a data input section for inputting and a locating means, the locating means locating a fault point from the input data and the received data of its own end, and the locating result based on the locating result. It is composed of means for determining whether the accident is near the branch point or not, and second orientation means for relocating when the accident is near the branch point.

First, the terminal device transmits the voltage and current data at each end to the central determination device. The central judgment device judges whether or not there is a fault near the branch point from the voltage and current at the self-end and the received voltage and current data. If the fault is near the branch point, the branch point voltage and the current flowing into the branch point are determined. Relocate the accident point using.

[0011]

Embodiments will be described below with reference to the drawings. Figure 1
FIG. 1 is a system configuration diagram in which a fault point locating device according to the present invention is applied to a power system. In FIG. 1, the same parts as those in FIG. 9 are designated by the same reference numerals and the description thereof will be omitted. Reference numeral 13 is a central determination device, which is provided with an orientation section 14 in place of the orientation section 9 of the conventional apparatus. The processing contents of the orientation section 14 will be described later.

The operation of the system is such that the data on the terminal device side is taken into the receiving section of the central judgment device 13 through the transmission line 12, and the data taken in here and the data input of the central judgment device are input. The location of the accident is located by the orientation section 14 based on the self-end data from the section. In addition, since the terminal device is not installed in the terminal 4 (cecal terminal), the amount of electricity cannot be input.

The outline will be described with reference to the system diagram of FIG. As shown above, FIG. 10 is a so-called cecal terminal, so that the terminal B is not provided with a terminal device. If an accident occurs at point F of the branch line, equation (9) holds. From equation (10), determine whether the accident is near the branch point or other accidents.

The accident near the branch point is judged to be near the branch point if the accident point locating device is within ± 2 km from the branch point. Based on the above conditions, the voltage and current data at the branch point are used for the impedance distance calculation. The voltage at the branch point and the current flowing into the cecal terminal are expressed by Eqs. (11) and (1
It becomes the formula 2). V _J = V _A −I _A Z _A ……… (11) I _C = I _A + I _B ……… (12)

In this case as well, since the fault point resistance Z _F can be assumed to be a pure resistance component, the current I _F flowing into the fault point and the fault point voltage V _F are in phase. Therefore, using the equation (2), the fault current I _F is calculated as I _F = I _C −I _C ′ = I _C ″. Note that I _C is the current before the accident, I _C ′ is the current after the accident, and I _C ″.
Is the changed current, which is the same as in the case of Eq. (3).
The so-called cecal terminal accident point can be located by the equation (13).

Next, the configuration and internal processing of the terminal device and the central judgment device will be described. FIG. 2 shows the functions of the terminal device. The data input means 30 inputs voltage and current data, samples the data, and converts the instantaneous value into analog / digital conversion. The data storage unit 302 stores the data for a certain time and sends the data collectively to the transmission unit 303.
The transmitting means 303 transmits the voltage and current data to the central judgment device.

FIG. 3 shows the function of the central judging device. The same parts (inside the one-dot chain line) as in FIG. First accident point locating means 101
Then, locate the accident point according to the equation (10). The accident determination means 102 determines whether the accident is near the branch point or not based on the orientation result of the first accident point orientation means 101.
As described above, if the orientation result is within ± 2 km from the junction, it is determined that the accident is near the junction. When the accident determining means 102 determines that the accident is other than the vicinity of the branch point, the orientation value of the first accident point locating means 101 is output as the orientation result 104. When the accident determining means 102 determines that the accident is near the branch point, the second accident point locating means 103 is executed and the result is output.

[0018]

As described above, according to the present invention, when there is a terminal in which no terminal device is installed in the system and an accident occurs after that terminal, it is first determined whether the accident is near the branch point. In the case of an accident near the branch point, the accident point is located using the branch point voltage and the current flowing into the branch terminal, so the so-called cecal terminal accident point where no terminal device is installed is located with high accuracy. it can.

[Brief description of drawings]

FIG. 1 is a system configuration diagram in which a fault location device is applied to a power system.

FIG. 2 is a diagram showing functions of a terminal device.

FIG. 3 is a diagram showing a function of a central determination device.

FIG. 4 is a diagram illustrating a distance type fault point locating device.

FIG. 5 is a power system diagram of FIG.

FIG. 6 is a power system diagram in which a distance type fault locator is applied to a system having a cecal terminal.

FIG. 7 is a diagram in which a collection type fault point locating device is applied to a two-terminal system.

8 is a power system diagram of FIG. 7.

FIG. 9 is a diagram in which the collecting-type fault point locating device is applied to a system having a cecal terminal.

FIG. 10 is a power system diagram of FIG. 9.

11 is a functional block diagram of the central determination device in FIG. 9.

[Explanation of symbols] 2,3,4 terminals 6 Terminal device 7,8 Data input unit 9,14 Orientation unit 10 Reception unit 11 Transmission unit 12 Transmission line 13 Central judgment unit

Front page continuation (72) Inventor Eiji Akamatsu 1-1-1, Shibaura, Minato-ku, Tokyo Toshiba Corporation Head Office

Claims (1)

[Claims] 1. A fault point locating device for locating a fault point by using voltage and current at each terminal of a multi-terminal transmission line, and data input means for inputting terminal voltage and current data and taken-in voltage and current. A central determination device including a terminal device including a transmission unit that transmits data, a reception unit that receives data transmitted from each terminal device, a data input unit that inputs voltage and current data of its own end, and an orientation unit. The locating means comprises first locating means for locating an accident point from input data and received data of its own end, means for deciding whether or not an accident near a branch point is based on the locating result, and A fault point locating device comprising: a second locating means for relocating when an accident is near the point.