JP3845770B2 - Protection device for power system and protection relay device using it - Google Patents

Description

  The present invention relates to a protection device for an electric power system that can further increase the location calculation speed of an accident point position, and a protection relay device that uses the protection device.

  2. Description of the Related Art A computer-based power system protection relay device capable of executing accident localization calculation with high accuracy by an equation derived from Kirchhoff's first law and second law is known (Patent Document 1). This system pre-calculates a fixed matrix based on the system configuration, and based on the operation data of the system collected by data sampling, uses the fixed matrix to locate the accident point position with high accuracy. An appropriate system protection function can be realized against any accident.

It is possible to realize a dynamic system protection function following the system configuration change by detecting the system configuration change, extracting the corresponding fixed matrix, and using the extracted fixed matrix (patent) Reference 2).
JP 2002-64926 A JP 2003-143747 A

  In the case of such a conventional technique, there is a problem that the calculation time may be excessive because the location calculation of the accident point position uses, for example, a repeated calculation by the Newton-Raphson method.

  Therefore, in view of the problems of the prior art, an object of the present invention is to provide a linear primary solution (LE method) for obtaining an approximate solution of an accident point position and an interpolation method (FK method) using the approximate solution of an accident point position. It is to provide a protection device for a power system capable of remarkably increasing the location calculation speed of an accident point position without using iterative calculation, and a protection relay device using the same. .

  The configuration of the first invention according to this application for achieving the object includes pre-calculation means for calculating and storing a fixed matrix based on facility data of the system, and constant calculation means that operates every data sampling. The pre-calculation means calculates and stores an intermediate matrix for calculating the accident point current at a plurality of points including the intermediate point of the section, and the constant calculation means is based on the operation data of the system collected by data sampling, Based on the basic equations derived from Kirchhoff's first law and second law, using the fixed matrix and the intermediate matrix stored by the pre-calculation means, the approximate solution of the accident point position can be calculated from the current at the middle point of the section. The gist is to determine the location of the fault point in the section from the fault point current at a plurality of points near the approximate solution. However, the protection device for the power system means a fault locator device for locating the accident point position or an oscillograph device for collecting accident data related to the system disturbance at the time of the accident.

  The constant calculation means can estimate and store the load current before the accident.

  In addition, the constant calculation means is provided with an accident section determination means, and the accident section determination means is based on the accident point position of each section specified by the constant calculation means and the fault point current of the sound line of each section. Accident section can be determined.

  The gist of the configuration of the second invention is that it includes the protection device for the power system according to the first invention and trip signal output means for outputting a trip signal in response to a trip command from the constant calculation means.

  According to the configuration of the first and second inventions, when the facility data including the system impedance is input, the pre-calculation means calculates and stores a fixed matrix that does not depend on the accident point position based on the facility data. Further, an intermediate matrix for calculating the fault point current at a plurality of points including the intermediate point of the section is calculated and stored. Therefore, the constant calculation means uses the fixed matrix and the intermediate matrix stored in advance by the pre-calculation means, and applies the linear primary solution method (LE method) and the interpolation method (FK method), thereby determining the accident point position of the section. It can be specified by calculating at a sufficiently high speed. This is because the constant calculation means does not need to perform repetitive calculation that requires a large amount of calculation time.

  The constant calculation means calculates the accident point current at the intermediate point using the intermediate matrix for calculating the accident point current at the intermediate point of the section stored by the prior calculation means, and the accident point position is calculated from this accident point current. Find an approximate solution (linear linear solution (LE method)), use the intermediate matrix for calculating the fault current at multiple points in the vicinity of the approximate solution, find the fault point current at multiple points, and use these fault point currents as the interval Can be specified (interpolation method (FK method)).

  The constant calculation means estimates and updates the load current before the accident, so that it is not necessary to use an expensive telemeter device and the like, and a complete one-end measurement type protective relay device can be configured. However, “pre-accident” here means, for example, one cycle before the occurrence of the accident.

  The accident section determination means that is always attached to the calculation means, when a multi-terminal transmission line including a plurality of sections is to be protected, even if an accident occurs near the branch point of the transmission line, By evaluating the magnitude of the fault point current on the sound line, it is possible to accurately determine the section where the accident actually occurred and contribute to improving the efficiency of the accident recovery work. The accident section determination means may prioritize the accident sections in order from the section where the fault point current of the sound line is small, and may rank the determination accuracy.

  According to the configuration of the second invention, by providing the trip signal output means, the accident line can be quickly cut off and disconnected, and the accident can be cleared.

BEST MODE FOR CARRYING OUT THE INVENTION

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The power system protection relay device 10 includes a pre-calculation unit 11, a constant calculation unit 13, a trip signal output unit 14, and an output unit 16 (FIG. 1). However, the protection relay device 10 is used for protection of the two-line transmission lines L1 and L2 that link the power transmission end including the power source G and the power reception end including the constant current load L, for example (FIG. 2). .

る。なお、図２には、その他の符号の説明が併せて表示されている。

The In FIG. 2, explanations of other symbols are also displayed.

０の事前計算手段１１に入力される（図１）。また、事前計算手段１１の出力は、事前データ記憶手段１２を介して常時計算手段１３に接続されており、常時計算手段１３には、

0 is input to the prior calculation means 11 (FIG. 1). The output of the advance calculation means 11 is connected to the constant calculation means 13 via the advance data storage means 12.

  One output of the constant calculation means 13 is input to the trip signal output means 14 as a trip command S1, and the output of the trip signal output means 14 is supplied as a trip signal S to the power transmission end side of each of the transmission lines L1 and L2. It is led to a circuit breaker (not shown). Further, another output of the constant calculation means 13 is connected to an output means 16 such as a printer device or a display device via the accident data storage means 15.

、プログラムは、まず、図５−２の（２．５）式、図５−３の（３．８）〜（３．１０）

_BWを計算し、固定マトリックスとして事前データ記憶手段１２に記憶する（図３のプログラムステップ（１）、以下、単に（１）のように記す）。なお、図５−１〜７は、事前計算手段１１、常時計算手段１３によって実行される一連の計算内容の技術的根拠を数式により説明しており、この説明における各式の番号は、図５−１〜７に記載の各式番号に対

（行列）、ベクトル量、スカラ量を表わす。 The pre-calculation means 11 inputs the impedances of the transmission lines L1 and L2 via a data input device (not shown)

First, the program is expressed by equation (2.5) in FIG. 5-2 and (3.8) to (3.10) in FIG. 5-3.

_BW is calculated and stored in the pre-data storage means 12 as a fixed matrix (program step (1) in FIG. 3, hereinafter simply referred to as (1)). 5A to 7 illustrate the technical basis of a series of calculation contents executed by the pre-calculation unit 11 and the constant calculation unit 13 by mathematical formulas. -1 to 7 for each formula number

(Matrix), vector quantity, scalar quantity.

を計算し、事故点電流計算用の中間マトリックスとして事前データ記憶手段１２に記憶して終了する（２）。なお、事故点電流計算用の中間マトリックスには、事故点位置ｋ＝０

トリックスとして必ず含まれるものとする。 Subsequently, the program divides the length of the transmission lines L1 and L2 into, for example, 10 equal parts,

Is stored in the preliminary data storage means 12 as an intermediate matrix for calculating the fault point current, and the process ends (2). Note that the fault point position k = 0 is included in the intermediate matrix for calculating the fault point current.

It must be included as a trick.

On the other hand, the constant calculation means 13 is activated, for example, every 30 ° of the system voltage waveform, that is, every time data sampling is set at a high frequency of 10 times or more of the system frequency, and operates according to the program flowchart of FIG. In other words, the constant calculation means 13

るに代えて、図示しないテレメータ装置を介してデータを送信し、常時計算手段１３のデータサンプリングの対象としてもよい。 The program first confirms that the accident is not ongoing (program steps in Figure 4).

Instead of this, data may be transmitted via a telemeter device (not shown), and the data may be constantly sampled by the calculation means 13.

とに計算する（３）。さらに、プログラムは、たとえば０．０５p.u.のしきい値を超える

を特定する（４）。なお、プログラムは、送電線Ｌ1 、Ｌ2 の各線に事故がなければ（５）、そのまま終了して次の作動まで待機する。 Subsequently, the program uses the intermediate matrix for calculating the fault current at the intermediate point of the section stored in the pre-data storage means 12 and transmits the transmission line according to the equation (2.8).

(3). In addition, the program exceeds the threshold of 0.05 p.u., for example.

(4). If there is no accident on each of the transmission lines L1 and L2 (5), the program ends and waits for the next operation.

（４．５）式に従って事故点位置ｋの近似解を求める（７）。次に、プログラムは、（５．１）〜（５．７）式に従って、事故点位置ｋの近似解の近傍で補間法（ＦＫ法）を適用し、事故点位置ｋを特定する（８）。 When the program detects an accident that occurred on either of the transmission lines L1 and L2 (5),

An approximate solution of the accident point position k is obtained according to equation (4.5) (7). Next, the program applies the interpolation method (FK method) in the vicinity of the approximate solution of the accident point position k according to the equations (5.1) to (5.7), and specifies the accident point position k (8). .

  In this way, the program of the constant calculation means 13 is established based on Kirchhoff's first law and second law by applying a series of calculation procedures shown in FIGS. 7) Based on the equations (1.1) to (1.4), and using the equations (2.6) and (3.7) derived from these equations as basic equations, linear linear solution (LE method) ) And the accident point position k can be specified through each calculation of the interpolation method (FK method).

  Subsequently, the program determines whether or not the specified accident point position k is within the section of the transmission lines L1 and L2 to be protected (9), and when it is outside the section, the program ends. On the other hand, when the accident point position k is in the section (9), the program outputs a trip command S1 to the trip signal output means 14 (10), and the trip signal output means 14 transmits the transmission lines L1, L2 Among them, a trip signal S is sent to the circuit breaker on the power transmission end side of the line including the accident line to cause a trip.

プログラムは、事故がしゃ断されるまで、この動作をデータサンプリングごとに繰り返す

事故データとして収集し、事故データ記憶手段１５に記憶させることができる。 After that, the program moves to the specified accident point position k according to equations (2.8) and (2.9).

The program repeats this action for each data sampling until the accident is cut off

It can be collected as accident data and stored in the accident data storage means 15.

タを出力手段１６に出力して（１３）、終了する。

Is output to the output means 16 (13), and the process ends.

Other embodiments

  Accident section determination means 17 can be attached to the constant calculation means 13 (FIG. 6).

  When the multi-terminal power transmission line having a plurality of sections is to be protected, for example, as shown in FIG. 7, the constant calculation means 13 sequentially executes the program steps (1) to (12) of FIG. 4 for each section. In this case, if an accident occurs in the vicinity of the branch point of the transmission line, a plurality of sections determined to be internal accidents may occur, and the accident section may not be specified. Therefore, when the accident is interrupted for all the sections (program steps (12) and (13) in FIG. 4), the constant calculation means 13 activates the accident section determination means 17, and the accident section determination means 17 It operates according to the program flowchart.

│を算出する（２）。ただし、Δは、事故点位置ｋの許容誤差であり、たとえばΔ＝０．０５に設定する。また、ｈ、ｈm は、それぞれ健全線の番号、本数であり、各健全線は、図４のプログラムステップ（４）により、事故線でない線として特定することができる。

発生から約１サイクル程度経過後のあらかじめ定めるタイミングにおけるデータを使用することが好ましい。 The program extracts a section in which the accident point position k of each section specified in the program step (8) in FIG. 4 is in the range of 0 ≦ k ≦ 1 + Δ (program step (1) in FIG. 8). 1)), and according to equations (2.8) and (2.9) in FIG.

│ is calculated (2). However, Δ is an allowable error of the accident point position k, and is set to Δ = 0.05, for example. H and hm are the number and number of sound lines, respectively, and each sound line can be specified as a line that is not an accident line by the program step (4) in FIG.

It is preferable to use data at a predetermined timing after about one cycle has elapsed since the occurrence.

Subsequently, when the program completes the check for all the sections (3), it determines that the section having the smallest average value i _fa is the accident section (4), and information on the accident section and the accident point position k in the accident section. Is output to the output means 16 (5), and the process ends. Since the actual accident section can be identified almost certainly, the efficiency of accident recovery work can be greatly improved.

．７）式または（４．１）式に従って算出することができる。 The operating principle of the present invention is also applied to power system protection devices such as a fault locator device for locating the accident point position k and an oscillograph device for collecting accident data related to system disturbance at the time of the accident. Is possible. However, for these applications, the trip command output function (program step (10) in FIG. 4) of the constant calculation means 13 or the trip signal output

. It can be calculated according to the equation (7) or (4.1).

Overall block diagram Application system diagram Program flow chart (1) Program flow chart (2) Calculation procedure explanatory diagram (1) Calculation procedure explanatory diagram (2) Calculation procedure explanatory diagram (3) Calculation procedure explanatory diagram (4) Calculation procedure explanatory diagram (5) Calculation procedure explanatory diagram (6) Calculation procedure explanatory diagram (7) Main part block system diagram showing another embodiment Application system diagram showing another embodiment Program flow chart showing another embodiment

Explanation of symbols

Ｓ1 …トリップ指令
Ｓ…トリップ信号
１０…保護リレー装置
１１…事前計算手段
１３…常時計算手段
１４…トリップ信号出力手段
１７…事故区間判定手段

特許出願人 辻 浩 一
株式会社 キューキ
代理人 弁理士 松 田 忠 秋 k ... Accident point location

DESCRIPTION OF SYMBOLS S1 ... Trip command S ... Trip signal 10 ... Protection relay apparatus 11 ... Prior calculation means 13 ... Constant calculation means 14 ... Trip signal output means 17 ... Accident section judgment means

Patent applicant Koichi Tsuji
Kuki Corporation
Attorney Tadaaki Matsuda, Attorney

Claims (4)

  A pre-calculation unit that calculates and stores a fixed matrix based on facility data of the system; and a constant calculation unit that operates every time data sampling is performed, and the pre-calculation unit includes a plurality of points including intermediate points of the section. An intermediate matrix for calculating the current at the fault point is calculated and stored, and the constant calculation means stores the fixed matrix and the intermediate matrix stored by the pre-calculation means based on the system operation data collected by data sampling. Based on the basic equations derived from Kirchhoff's first law and second law, an approximate solution of the accident point position is obtained from the accident point current at the middle point of the section, and the accident point currents at multiple points near the approximate solution are used. A device for protecting a power system, characterized in that the position of an accident point in a section is specified.   2. The power system protection device according to claim 1, wherein the constant calculation means estimates and updates a load current before an accident.   The constant calculation means is provided with accident section determination means, and the accident section determination means is based on the fault point position of each section specified by the constant calculation means and the fault point current of the healthy line of each section. 3. The power system protection device according to claim 1, wherein an accident section is determined.   4. A power system protection relay device comprising: the power system protection device according to claim 1; and trip signal output means for outputting a trip signal in response to a trip command from the constant calculation means. .

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