CN108414843B - Method for discriminating direct lightning strike from inductive lightning strike based on optical integrated electric field sensor - Google Patents

Abstract

The invention relates to a method for judging direct lightning and induction lightning based on an optical integrated electric field sensor, belonging to the technical field of fault identification. The method is based on the measurement data of the optical integrated electric field sensor, the lightning overvoltage at two ends of the three-phase independent insulator is separated from the original waveform through methods of filtering, overvoltage extraction, decoupling and the like, and direct lightning strike and inductive lightning strike are judged according to the polarity of the three-phase lightning overvoltage. The method has the advantages of convenient installation and test and high fault identification rate through practical verification.

Description

Translated fromChinese

基于光学集成电场传感器的直击雷和感应雷的判别方法Discrimination method of direct lightning strike and induction lightning based on optical integrated electric field sensor

技术领域technical field

本发明涉及一种基于光学集成电场传感器的直击雷和感应雷的判别方法，属于故障识别技术领域。The invention relates to a method for judging direct strike lightning and induction lightning based on an optical integrated electric field sensor, and belongs to the technical field of fault identification.

背景技术Background technique

高压架空输电线路是电力系统中重要组成部分，其分布很广、纵横交错、绵延数百里乃至上千公里，所以极易受雷击。雷电过电压分为直击雷过电压和感应雷过电压。直击雷是指雷电直接击中电气设备、线路或建筑物，引起强大的雷电流流过这些物体导致在整个系统过电压；感应雷是指雷云对地放电过程中，放电通道周围空间的电磁场发生急剧变化，在附近导体上产生感应雷过电压。High-voltage overhead transmission lines are an important part of the power system. They are widely distributed, crisscross, and stretch for hundreds of miles or even thousands of kilometers, so they are extremely vulnerable to lightning strikes. Lightning overvoltage is divided into direct lightning overvoltage and induced lightning overvoltage. Direct lightning means that lightning strikes electrical equipment, lines or buildings directly, causing a strong lightning current to flow through these objects and cause overvoltage in the entire system; induction lightning refers to the electromagnetic field in the space around the discharge channel during the discharge process of the thundercloud to the ground. A sharp change occurs, resulting in induced lightning overvoltages on nearby conductors.

统计资料显示，我国高压架空输电线路由雷击引起的跳闸次数占运行总跳闸次数的40％-70％。对于大于110kV的高压输电线路，直击雷过电压对线路绝缘的危险最为严重，但它只占雷击率的10％。我国主要配电网6～35kV电网由于绝大多数无避雷线保护，自身绝缘水平较低，最易发生雷害事故，低压配电系统由感应雷引起的故障率大于90％。雷击可能引起线路开关跳闸造成停电事故，还会造成电气设备损坏，甚至导致电力系统瓦解等恶性事故，造成重大的经济损失，严重影响电力系统运行的稳定性、可靠性、安全性和经济性。Statistics show that the number of trips caused by lightning strikes on high-voltage overhead transmission lines in my country accounts for 40%-70% of the total trips in operation. For high-voltage transmission lines greater than 110kV, the direct lightning overvoltage has the most serious danger to the line insulation, but it only accounts for 10% of the lightning strike rate. Most of the 6-35kV power grids in my country's main distribution network have no lightning protection line protection, and their own insulation level is low, and lightning accidents are most likely to occur. The failure rate of low-voltage distribution systems caused by induction lightning is greater than 90%. Lightning strikes may cause line switches to trip and cause power outages, damage electrical equipment, and even lead to vicious accidents such as the collapse of the power system, resulting in major economic losses and a serious impact on the stability, reliability, safety and economy of power system operation.

由于直击雷和感应雷产生的机理不同，造成的故障类型和防护手段也各不相同，故应该对直击雷和感应雷进行辨识，为防雷设计提供依据，有针对性地采取防雷措施，可提高线路防雷水平。Due to the different mechanisms of direct lightning strike and induction lightning, the types of faults and protection measures caused are also different. Therefore, direct lightning strike and induction lightning should be identified to provide a basis for lightning protection design, and lightning protection measures should be taken in a targeted manner. It can improve the lightning protection level of the line.

发明内容SUMMARY OF THE INVENTION

本发明目的是提出一种基于光学集成电场传感器的直击雷和感应雷的判别方法，基于光学集成电场传感器的测量数据，通过滤波、过电压提取、解耦等方法，将三相独立的绝缘子两端的雷电过电压从原始波形中分离出来，根据三相雷电过电压的极性来判别直击雷和感应雷。The purpose of the present invention is to propose a method for judging direct lightning strikes and induced lightning based on optical integrated electric field sensors. Based on the measurement data of optical integrated electric field sensors, through filtering, overvoltage extraction, decoupling and other methods, the three-phase independent insulators are divided into two parts. The lightning overvoltage at the terminal is separated from the original waveform, and the direct lightning and induced lightning are judged according to the polarity of the three-phase lightning overvoltage.

本发明提出的基于光学集成电场传感器的直击雷和感应雷的判别方法，包括以下步骤：The method for judging the direct lightning strike and the induction lightning based on the optical integrated electric field sensor proposed by the present invention includes the following steps:

(1)将三台光学集成电场传感器分别安装在变电站中待测量线路的正下方，使三台光学集成电场传感器的离地高度相同，并使三台光学集成电场传感器的极性朝向一致，分别对三台光学集成电场传感器通光，以在线监测待测量线路上雷电过电压的波形；(1) Install the three optically integrated electric field sensors directly under the line to be measured in the substation, so that the heights of the three optically integrated electric field sensors are the same from the ground, and the polarities of the three optically integrated electric field sensors are in the same direction. Pass light to three optical integrated electric field sensors to monitor the waveform of lightning overvoltage on the line to be measured online;

(2)当待测量线路有直击雷或者感应雷发生时，三台光学集成电场传感器分别测量得到电场波形，该电场信号由雷电过电压电场波形和三相工频电场波形叠加而成，利用小波变化或平均滤波方法，对测量得到的电场波形进行滤波处理，得到滤波后的电场波形，并对测量得到的电场波形分别乘以相应光学集成电场传感器的转化因数，得到测量电压波形，其中，光学集成电场传感器的转化因数为测量电场是1V/m时所对应的实际电压值；(2) When the line to be measured has a direct lightning strike or an induced lightning strike, the three optical integrated electric field sensors measure the electric field waveform respectively. The electric field signal is composed of the lightning overvoltage electric field waveform and the three-phase power frequency electric field waveform. The variation or average filtering method is to filter the measured electric field waveform to obtain the filtered electric field waveform, and multiply the measured electric field waveform by the conversion factor of the corresponding optical integrated electric field sensor to obtain the measured voltage waveform. The conversion factor of the integrated electric field sensor is the actual voltage value corresponding to when the measured electric field is 1V/m;

(3)将上述步骤(2)的测量电压波形，与由变电站中三台光学集成电场传感器在未发生雷击时对待测量线路测量得到同相位下的工频电压波形相减，得到待测量线路的互有耦合三相雷电过电压波形；(3) Subtract the measured voltage waveform of the above step (2) with the power frequency voltage waveform under the same phase obtained by measuring the line to be measured by the three optical integrated electric field sensors in the substation when no lightning strike occurs, to obtain the voltage waveform of the line to be measured. Mutual coupling three-phase lightning overvoltage waveform;

(4)对上述互有耦合三相雷电过电压波形进行解耦，设互有耦合三相雷电过电压波形为U_A、U_B、U_C，解耦后的三相雷电过电压波形为U_a、U_b、U_c，建立如下解耦方程：(4) Decouple the above-mentioned mutually coupled three-phase lightning overvoltage waveforms, set the mutually coupled three-phase lightning overvoltage waveforms as U_A , U_B , and U_C , and the decoupled three-phase lightning overvoltage waveform is U_a , U_b , U_c , the following decoupling equations are established:

其中，q_ij为解耦系数，i＝1，2，3，j＝1，2，3，q_ij∈[0，100]；Among them, q_ij is the decoupling coefficient, i=1, 2, 3, j=1, 2, 3, q_ij ∈ [0, 100];

(5)对解耦后的三相雷电过电压波形U_a、U_b、U_c的极性进行判断，若三相雷电过电压波形U_a、U_b、U_c的极性相同，则判定待测量线路发生了感应雷，若三相雷电过电压波形U_a、U_b、U_c的极性不同，则判定待测量线路上发生了直击雷。(5) Judge the polarities of the three-phase lightning overvoltage waveforms U_a , U_b , and U_c after decoupling. If the polarities of the three-phase lightning over-voltage waveforms U_a , U_b , and U_c are the same, then judge Induction lightning occurs on the line to be measured. If the polarities of the three-phase lightning overvoltage waveforms U_a , U_b , and U_c are different, it is determined that a direct lightning strike occurs on the line to be measured.

本发明提出的基于光学集成电场传感器的直击雷和感应雷的判别方法，其优点是：The method for judging direct lightning strikes and induction lightning based on optical integrated electric field sensors proposed by the present invention has the following advantages:

1、本发明方法中使用光学集成电场传感器，具有安装方便，便于测量的特点。1. The optical integrated electric field sensor is used in the method of the present invention, which has the characteristics of convenient installation and convenient measurement.

2、本发明方法经实际验证，可有效的判别待测量线路上的直击雷和感应雷。2. The method of the present invention has been verified in practice, and can effectively discriminate between direct lightning strikes and induction lightning on the line to be measured.

具体实施方式Detailed ways

本发明提出的基于光学集成电场传感器的直击雷和感应雷的判别方法，包括以下步骤：The method for judging the direct lightning strike and the induction lightning based on the optical integrated electric field sensor proposed by the present invention includes the following steps:

(1)将三台光学集成电场传感器(本发明的一个实施例中，使用的三相光学集成电场传感器由清华大学生产，可参见公开号为CN102854403B的中国专利申请)分别安装在变电站中待测量线路的正下方，使三台光学集成电场传感器的离地高度相同，并使三台光学集成电场传感器的极性朝向一致，分别对三台光学集成电场传感器通光，以在线监测待测量线路上雷电过电压的波形；(1) Three optically integrated electric field sensors (in one embodiment of the present invention, the used three-phase optically integrated electric field sensors are produced by Tsinghua University, please refer to the Chinese patent application with publication number CN102854403B) respectively installed in the substation to be measured Directly below the line, make the three optical integrated electric field sensors have the same height from the ground, and make the polarities of the three optical integrated electric field sensors the same, respectively pass light to the three optical integrated electric field sensors to monitor the line to be measured online. The waveform of lightning overvoltage;

(2)当待测量线路有直击雷或者感应雷发生时，三台光学集成电场传感器分别测量得到电场波形，该电场信号由雷电过电压电场波形和三相工频电场波形叠加而成，利用小波变化或平均滤波方法，对测量得到的电场波形进行滤波处理，得到滤波后的电场波形，并对测量得到的电场波形分别乘以相应光学集成电场传感器的转化因数，得到测量电压波形，其中，光学集成电场传感器的转化因数为测量电场是1V/m时所对应的实际电压值；(2) When the line to be measured has a direct lightning strike or an induced lightning strike, the three optical integrated electric field sensors measure the electric field waveform respectively. The electric field signal is composed of the lightning overvoltage electric field waveform and the three-phase power frequency electric field waveform. The variation or average filtering method is to filter the measured electric field waveform to obtain the filtered electric field waveform, and multiply the measured electric field waveform by the conversion factor of the corresponding optical integrated electric field sensor to obtain the measured voltage waveform. The conversion factor of the integrated electric field sensor is the actual voltage value corresponding to when the measured electric field is 1V/m;

(3)将上述步骤(2)的测量电压波形，与由变电站中三台光学集成电场传感器在未发生雷击时对待测量线路测量得到同相位下的工频电压波形相减，得到待测量线路的互有耦合三相雷电过电压波形；(3) Subtract the measured voltage waveform of the above step (2) with the power frequency voltage waveform under the same phase obtained by measuring the line to be measured by the three optical integrated electric field sensors in the substation when no lightning strike occurs, to obtain the voltage waveform of the line to be measured. Mutual coupling three-phase lightning overvoltage waveform;

(4)对上述互有耦合三相雷电过电压波形进行解耦，设互有耦合三相雷电过电压波形为U_A、U_B、U_C，解耦后的三相雷电过电压波形为U_a、U_b、U_c，建立如下解耦方程：(4) Decouple the above-mentioned mutually coupled three-phase lightning overvoltage waveforms, set the mutually coupled three-phase lightning overvoltage waveforms as U_A , U_B , and U_C , and the decoupled three-phase lightning overvoltage waveform is U_a , U_b , U_c , the following decoupling equations are established:

其中，q_ij为解耦系数，i＝1，2，3，j＝1，2，3，q_ij∈[0，100]；Among them, q_ij is the decoupling coefficient, i=1, 2, 3, j=1, 2, 3, q_ij ∈ [0, 100];

(5)对解耦后的三相雷电过电压波形U_a、U_b、U_c的极性进行判断，若三相雷电过电压波形U_a、U_b、U_c的极性相同，则判定待测量线路发生了感应雷，若三相雷电过电压波形U_a、U_b、U_c的极性不同，则判定待测量线路上发生了直击雷。(5) Judge the polarities of the three-phase lightning overvoltage waveforms U_a , U_b , and U_c after decoupling. If the polarities of the three-phase lightning over-voltage waveforms U_a , U_b , and U_c are the same, then judge Induction lightning occurs on the line to be measured. If the polarities of the three-phase lightning overvoltage waveforms U_a , U_b , and U_c are different, it is determined that a direct lightning strike occurs on the line to be measured.

Claims (1)

Translated fromChinese

1.一种基于光学集成电场传感器的直击雷和感应雷的判别方法，其特征在于该方法包括以下步骤：1. a discrimination method based on the direct lightning strike of optical integrated electric field sensor and induction lightning, is characterized in that this method comprises the following steps:(1)将三台光学集成电场传感器分别安装在变电站中待测量线路的正下方，使三台光学集成电场传感器的离地高度相同，并使三台光学集成电场传感器的极性朝向一致，分别对三台光学集成电场传感器通光，以在线监测待测量线路上雷电过电压的波形；(1) Install the three optically integrated electric field sensors directly under the line to be measured in the substation, so that the heights of the three optically integrated electric field sensors are the same from the ground, and the polarities of the three optically integrated electric field sensors are in the same direction. Pass light to three optical integrated electric field sensors to monitor the waveform of lightning overvoltage on the line to be measured online;(2)当待测量线路有直击雷或者感应雷发生时，三台光学集成电场传感器分别测量得到电场波形，该电场波形由雷电过电压电场波形和三相工频电场波形叠加而成，利用小波变化或平均滤波方法，对测量得到的电场波形进行滤波处理，得到滤波后的电场波形，并对滤波后的电场波形分别乘以相应光学集成电场传感器的转化因数，得到测量电压波形，其中，光学集成电场传感器的转化因数为测量电场是1V/m时所对应的实际电压值；(2) When there is direct lightning strike or induced lightning on the line to be measured, the three optical integrated electric field sensors measure the electric field waveform respectively. The electric field waveform is superimposed by the lightning overvoltage electric field waveform and the three-phase power frequency electric field waveform. The variation or average filtering method is to filter the measured electric field waveform to obtain the filtered electric field waveform, and multiply the filtered electric field waveform by the conversion factor of the corresponding optical integrated electric field sensor to obtain the measured voltage waveform. The conversion factor of the integrated electric field sensor is the actual voltage value corresponding to when the measured electric field is 1V/m;(3)将上述步骤(2)的测量电压波形，与由变电站中三台光学集成电场传感器在未发生雷击时对待测量线路测量得到同相位下的工频电压波形相减，得到待测量线路的互有耦合三相雷电过电压波形；(3) Subtract the measured voltage waveform of the above step (2) with the power frequency voltage waveform under the same phase obtained by measuring the line to be measured by the three optical integrated electric field sensors in the substation when no lightning strike occurs, to obtain the voltage waveform of the line to be measured. Mutual coupling three-phase lightning overvoltage waveform;(4)对上述互有耦合三相雷电过电压波形进行解耦，设互有耦合三相雷电过电压波形为U_A、U_B、U_C，解耦后的三相雷电过电压波形为U_a、U_b、U_c，建立如下解耦方程：(4) Decouple the above-mentioned mutually coupled three-phase lightning overvoltage waveforms, set the mutually coupled three-phase lightning overvoltage waveforms as U_A , U_B , and U_C , and the decoupled three-phase lightning overvoltage waveform is U_a , U_b , U_c , the following decoupling equations are established:其中，q_ij为解耦系数，i＝1，2，3，j＝1，2，3，q_ij∈[0，100]；Among them, q_ij is the decoupling coefficient, i=1, 2, 3, j=1, 2, 3, q_ij ∈ [0, 100];(5)对解耦后的三相雷电过电压波形U_a、U_b、U_c的极性进行判断，若三相雷电过电压波形U_a、U_b、U_c的极性相同，则判定待测量线路发生了感应雷，若三相雷电过电压波形U_a、U_b、U_c的极性不同，则判定待测量线路上发生了直击雷。(5) Judge the polarities of the three-phase lightning overvoltage waveforms U_a , U_b , and U_c after decoupling. If the polarities of the three-phase lightning over-voltage waveforms U_a , U_b , and U_c are the same, then judge Induction lightning occurs on the line to be measured. If the polarities of the three-phase lightning overvoltage waveforms U_a , U_b , and U_c are different, it is determined that a direct lightning strike occurs on the line to be measured.