CN106291221A - A kind of same tower double back transmission line adjacent lines broken string recognition methods - Google Patents

Abstract

Translated fromChinese

本发明公开一种同塔双回输电线路相邻线断线识别方法，包括如下步骤：步骤1，采集线路保护安装处的三相电流和三相电压；步骤2，计算线路保护安装处的零序电流和零序电压；步骤3，根据线路保护安装处零序电压、零序电流及输电线路零序阻抗推算虚拟零序电压；步骤4，比较线路保护安装处的零序电压以及推算的虚拟零序电压相位关系，若线路保护安装处的零序电压超前虚拟零序电压相位接近于180度，则判定线路保护安装线路的相邻线发生断线。此种方法可有助于在同塔双回输电线路中，避免非断线线路继电保护误动作。

The invention discloses a method for identifying the disconnection of adjacent lines of a double-circuit power transmission line on the same tower, which comprises the following steps: Step 1, collecting three-phase current and three-phase voltage at the place where the line protection is installed; sequence current and zero-sequence voltage; step 3, calculate the virtual zero-sequence voltage according to the zero-sequence voltage, zero-sequence current and transmission line zero-sequence impedance of the line protection installation; step 4, compare the zero-sequence voltage of the line protection installation and the calculated virtual zero-sequence Zero-sequence voltage phase relationship, if the zero-sequence voltage at the line protection installation is close to 180 degrees ahead of the virtual zero-sequence voltage phase, it is determined that the adjacent line of the line protection installation line is disconnected. This method can help to avoid malfunction of relay protection of non-broken lines in double-circuit transmission lines on the same tower.

Description

Translated fromChinese

一种同塔双回输电线路相邻线断线识别方法A Disconnection Identification Method for Adjacent Lines of Double-circuit Transmission Lines on the Same Tower

技术领域technical field

本发明属于电力系统继电保护领域，特别涉及一种同塔双回输电线路相邻线断线识别方法。The invention belongs to the field of relay protection of electric power systems, and in particular relates to a method for identifying disconnection of adjacent lines of double-circuit power transmission lines on the same tower.

背景技术Background technique

同塔双回输电线路在超高压输电网中得到广泛的应用。在大电流接地系统中，同塔双回输电线路中的一回线发生断线不接地的纵向故障，相邻输电线路的纵联零序方向保护采用常规的带零序电压补偿的零序方向测量方法时，可能造成非断线输电线路的两侧零序功率方向均判为正方向动作跳闸，从而造成停电范围扩大。Double-circuit transmission lines on the same tower are widely used in EHV transmission networks. In a large-current grounding system, if a longitudinal fault occurs in one of the double-circuit transmission lines on the same tower and is not grounded, the longitudinal zero-sequence directional protection of adjacent transmission lines adopts the conventional zero-sequence directional protection with zero-sequence voltage compensation When the measurement method is used, it may cause the zero-sequence power direction on both sides of the non-broken transmission line to be judged as a positive direction action trip, thereby causing the scope of power outage to expand.

在国外某些厂家的线路保护装置中，配置了线路断线监测功能的元件，但是此类元件其根本目的是监测断线的输电线路，而对于同塔双回输电线路中则并未考虑如何监测相邻线路出现断线的情况。因此，有必要对此问题进行深入研究，提出同塔双回输电线路中识别相邻线断线的方法，本案由此产生。In the line protection devices of some foreign manufacturers, components with line disconnection monitoring function are configured, but the fundamental purpose of such components is to monitor broken transmission lines, and how to Monitor for disconnection of adjacent lines. Therefore, it is necessary to carry out in-depth research on this issue and propose a method for identifying the disconnection of adjacent lines in double-circuit transmission lines on the same tower, and this case arose from this.

发明内容Contents of the invention

本发明的目的，在于提供一种同塔双回输电线路相邻线断线识别方法，其可有助于在同塔双回输电线路中，避免非断线线路继电保护误动作。The purpose of the present invention is to provide a method for identifying disconnection of adjacent lines of double-circuit transmission lines on the same tower, which can help to avoid malfunction of relay protection of non-broken lines in double-circuit transmission lines on the same tower.

为了达成上述目的，本发明的解决方案是：In order to achieve the above object, the solution of the present invention is:

一种同塔双回输电线路相邻线断线识别方法，包括如下步骤：A method for identifying disconnection of adjacent lines of a double-circuit transmission line on the same tower, comprising the following steps:

步骤1，采集线路保护安装处的三相电流和三相电压；Step 1, collect the three-phase current and three-phase voltage at the place where the line protection is installed;

步骤2，计算线路保护安装处的零序电流和零序电压；Step 2, calculate the zero-sequence current and zero-sequence voltage at the place where the line protection is installed;

步骤3，根据线路保护安装处零序电压、零序电流及输电线路零序阻抗推算虚拟零序电压；Step 3, calculate the virtual zero-sequence voltage according to the zero-sequence voltage, zero-sequence current and zero-sequence impedance of the transmission line where the line protection is installed;

步骤4，比较线路保护安装处的零序电压以及推算的虚拟零序电压相位关系，若线路保护安装处的零序电压超前虚拟零序电压相位接近于180度，则判定线路保护安装线路的相邻线发生断线。Step 4: Compare the zero-sequence voltage at the installation site of the line protection with the calculated phase relationship of the virtual zero-sequence voltage. If the zero-sequence voltage at the installation site of the line protection leads the phase of the virtual zero-sequence voltage by close to 180 degrees, determine the phase relationship of the line protection installation line. A disconnection occurred on an adjacent line.

上述步骤2中，零序电流的计算公式是：In the above step 2, the calculation formula of zero sequence current is:

$\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>0</span>0</span>}}<span><span>=</span>=</span>{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>A</span>A</span>}}<span><span>+</span>+</span>{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>B</span>B</span>}}<span><span>+</span>+</span>{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>C</span>C</span>}}$

其中，分别是线路保护安装处的三相电流。in, are the three-phase currents at the line protection installation respectively.

上述步骤2中，零序电压的计算公式是：In the above step 2, the calculation formula of the zero sequence voltage is:

$\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>0</span>0</span>}}<span><span>=</span>=</span>{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>A</span>A</span>}}<span><span>+</span>+</span>{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>B</span>B</span>}}<span><span>+</span>+</span>{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>C</span>C</span>}}$

其中，分别是线路保护安装处的三相电压。in, They are the three-phase voltages where the line protection is installed.

上述步骤3中，根据线路保护安装处零序电压、零序电流及输电线路零序阻抗推算虚拟零序电压的公式是：In the above step 3, the formula for calculating the virtual zero-sequence voltage according to the zero-sequence voltage and zero-sequence current at the line protection installation site and the zero-sequence impedance of the transmission line is:

$\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>0</span>0</span>}}^{<span><span>\&prime;</span>\&prime;</span>}<span><span>=</span>=</span>\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>0</span>0</span>}}<span><span>-</span>-</span>\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>0</span>0</span>}}{\mathrm{<span><span>Z</span>Z</span>}}_{\mathrm{<span><span>L</span>L</span>}\mathrm{<span><span>0</span>0</span>}}$

其中，Z_L0为输电线路零序阻抗，为零序电压，为零序电流，为虚拟零序电压。Among them, Z_L0 is the zero-sequence impedance of the transmission line, is the zero-sequence voltage, is the zero-sequence current, is the virtual zero-sequence voltage.

上述步骤4中，若满足：In step 4 above, if the following conditions are met:

则判定相邻线发生断线，其中，为线路保护安装处的零序电压超前于虚拟零序电压角度，为预设角度。Then it is determined that the adjacent line is disconnected, where, The zero-sequence voltage at the line protection installation is ahead of the virtual zero-sequence voltage angle, is the preset angle.

采用上述方案后，本发明根据线路保护安装处零序电压以及虚拟零序电压的相位关系，准确地判别线路保护安装线路的相邻线是否发生断线，应用于同塔双回输电线路中一回线断线，非断线线路中相邻线发生断线的判定，有助于在同塔双回输电线路中，避免非断线线路继电保护误动作。After adopting the above scheme, the present invention accurately judges whether the adjacent line of the line protection installation line is disconnected according to the phase relationship of the zero-sequence voltage at the installation site of the line protection and the virtual zero-sequence voltage, and is applied to a double-circuit transmission line on the same tower. The determination of the breakage of the return line and the breakage of the adjacent line in the non-broken line helps to avoid the malfunction of the relay protection of the non-broken line in the double-circuit transmission line on the same tower.

附图说明Description of drawings

图1是本发明的流程图。Fig. 1 is a flow chart of the present invention.

具体实施方式detailed description

以下将结合附图，对本发明的技术方案进行详细说明。The technical solutions of the present invention will be described in detail below in conjunction with the accompanying drawings.

如图1所示，本发明提供一种同塔双回输电线路相邻线断线识别方法，包括如下步骤：As shown in Figure 1, the present invention provides a method for identifying the disconnection of adjacent lines of double-circuit transmission lines on the same tower, including the following steps:

步骤1，采集线路保护安装处的三相电流和三相电压；Step 1, collect the three-phase current and three-phase voltage at the place where the line protection is installed;

在本实施例中，设采集到的三相电流分别是三相电压分别是In this embodiment, it is assumed that the collected three-phase currents are respectively The three-phase voltages are

步骤2，计算线路保护安装处的零序电流和零序电压；Step 2, calculate the zero-sequence current and zero-sequence voltage at the place where the line protection is installed;

具体的，计算线路保护安装处的零序电流和零序电压的方法是：Specifically, the method for calculating the zero-sequence current and zero-sequence voltage at the line protection installation is:

零序电流：Zero sequence current:

零序电压：Zero sequence voltage:

步骤3，根据线路保护安装处零序电压、零序电流及输电线路零序阻抗推算虚拟零序电压，可根据如下公式进行推算：Step 3. Calculate the virtual zero-sequence voltage according to the zero-sequence voltage, zero-sequence current and zero-sequence impedance of the transmission line where the line protection is installed. It can be calculated according to the following formula:

$\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>0</span>0</span>}}^{<span><span>\&prime;</span>\&prime;</span>}<span><span>=</span>=</span>\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>0</span>0</span>}}<span><span>-</span>-</span>\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>0</span>0</span>}}{\mathrm{<span><span>Z</span>Z</span>}}_{\mathrm{<span><span>L</span>L</span>}\mathrm{<span><span>0</span>0</span>}}$

其中，Z_L0为输电线路零序阻抗，为零序电压，为零序电流，为虚拟零序电压。Among them, Z_L0 is the zero-sequence impedance of the transmission line, is the zero-sequence voltage, is the zero-sequence current, is the virtual zero-sequence voltage.

步骤4，比较线路保护安装处的零序电压以及推算的虚拟零序电压相位关系，若线路保护安装处的零序电压超前虚拟零序电压相位接近于180度，则判定线路保护安装线路的相邻线发生断线。Step 4: Compare the zero-sequence voltage at the installation site of the line protection with the calculated phase relationship of the virtual zero-sequence voltage. If the zero-sequence voltage at the installation site of the line protection leads the phase of the virtual zero-sequence voltage by close to 180 degrees, determine the phase relationship of the line protection installation line. A disconnection occurred on an adjacent line.

其中，线路保护安装处的零序电压和虚拟零序电压相位关系的判定公式是：Among them, the judgment formula of the phase relationship between the zero-sequence voltage and the virtual zero-sequence voltage at the installation place of the line protection is:

其中，为线路保护安装处的零序电压超前于虚拟零序电压角度，为一个较小的角度，可根据具体情况进行设置。in, The zero-sequence voltage at the line protection installation is ahead of the virtual zero-sequence voltage angle, It is a small angle, which can be set according to the specific situation.

即：which is:

若则判定相邻线发生断线；like Then it is determined that the adjacent line is disconnected;

若或则判定相邻线未发生断线。like or Then it is judged that no disconnection occurs in the adjacent line.

以上实施例仅为说明本发明的技术思想，不能以此限定本发明的保护范围，凡是按照本发明提出的技术思想，在技术方案基础上所做的任何改动，均落入本发明保护范围之内。The above embodiments are only to illustrate the technical ideas of the present invention, and can not limit the protection scope of the present invention with this. All technical ideas proposed in accordance with the present invention, any changes made on the basis of technical solutions, all fall within the protection scope of the present invention. Inside.

Claims (5)

Translated fromChinese

1.一种同塔双回输电线路相邻线断线识别方法，其特征在于包括如下步骤：1. A method for identifying broken lines of adjacent lines of the same tower double-circuit transmission line, characterized in that it comprises the steps:步骤1，采集线路保护安装处的三相电流和三相电压；Step 1, collect the three-phase current and three-phase voltage at the place where the line protection is installed;步骤2，计算线路保护安装处的零序电流和零序电压；Step 2, calculate the zero-sequence current and zero-sequence voltage at the place where the line protection is installed;步骤3，根据线路保护安装处零序电压、零序电流及输电线路零序阻抗推算虚拟零序电压；Step 3, calculate the virtual zero-sequence voltage according to the zero-sequence voltage, zero-sequence current and zero-sequence impedance of the transmission line where the line protection is installed;步骤4，比较线路保护安装处的零序电压以及推算的虚拟零序电压相位关系，若线路保护安装处的零序电压超前虚拟零序电压相位接近于180度，则判定线路保护安装线路的相邻线发生断线。Step 4: Compare the zero-sequence voltage at the installation site of the line protection with the calculated phase relationship of the virtual zero-sequence voltage. If the zero-sequence voltage at the installation site of the line protection leads the phase of the virtual zero-sequence voltage by close to 180 degrees, determine the phase relationship of the line protection installation line. A disconnection occurred on an adjacent line.2.如权利要求1所述的一种同塔双回输电线路相邻线断线识别方法，其特征在于：所述步骤2中，零序电流的计算公式是：2. a kind of same-tower double-circuit transmission line adjacent line disconnection identification method as claimed in claim 1, is characterized in that: in described step 2, the calculation formula of zero-sequence current is:$\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>0</span>0</span>}}<span><span>=</span>=</span>{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>A</span>A</span>}}<span><span>+</span>+</span>{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>B</span>B</span>}}<span><span>+</span>+</span>{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>C</span>C</span>}}$其中，分别是线路保护安装处的三相电流。in, are the three-phase currents at the line protection installation respectively.3.如权利要求1所述的一种同塔双回输电线路相邻线断线识别方法，其特征在于：所述步骤2中，零序电压的计算公式是：3. a kind of same-tower double-circuit transmission line adjacent line disconnection identification method as claimed in claim 1, is characterized in that: in described step 2, the calculation formula of zero-sequence voltage is:$\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>0</span>0</span>}}<span><span>=</span>=</span>{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>A</span>A</span>}}<span><span>+</span>+</span>{\stackrel{<span><span>\&CenterDot;</span>\&Center\; Dot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>B</span>B</span>}}<span><span>+</span>+</span>{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>C</span>C</span>}}$其中，分别是线路保护安装处的三相电压。in, They are the three-phase voltages where the line protection is installed.4.如权利要求1所述的一种同塔双回输电线路相邻线断线识别方法，其特征在于：所述步骤3中，根据线路保护安装处零序电压、零序电流及输电线路零序阻抗推算虚拟零序电压的公式是：4. A method for identifying broken lines of adjacent double-circuit transmission lines on the same tower as claimed in claim 1, characterized in that: in said step 3, according to the zero-sequence voltage, zero-sequence current and transmission line The formula for calculating the virtual zero-sequence voltage from the zero-sequence impedance is:$\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>0</span>0</span>}}^{<span><span>\&prime;</span>\&prime;</span>}<span><span>=</span>=</span>\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>U</span>u</span>}}}_{\mathrm{<span><span>0</span>0</span>}}<span><span>-</span>-</span>\mathrm{<span><span>3</span>3</span>}{\stackrel{<span><span>\&CenterDot;</span>\&CenterDot;</span>}{\mathrm{<span><span>I</span>I</span>}}}_{\mathrm{<span><span>0</span>0</span>}}{\mathrm{<span><span>Z</span>Z</span>}}_{\mathrm{<span><span>L</span>L</span>}\mathrm{<span><span>0</span>0</span>}}$其中，Z_L0为输电线路零序阻抗，为零序电压，为零序电流，为虚拟零序电压。Among them, Z_L0 is the zero-sequence impedance of the transmission line, is the zero-sequence voltage, is the zero-sequence current, is the virtual zero-sequence voltage.5.如权利要求1所述的一种同塔双回输电线路相邻线断线识别方法，其特征在于：所述步骤4中，若满足：5. A method for identifying disconnection of adjacent lines of double-circuit transmission lines on the same tower as claimed in claim 1, characterized in that: in said step 4, if it satisfies:则判定相邻线发生断线，其中，为线路保护安装处的零序电压超前于虚拟零序电压角度，为预设角度。Then it is determined that the adjacent line is disconnected, where, The zero-sequence voltage at the line protection installation is ahead of the virtual zero-sequence voltage angle, is the default angle.