輸電線路雷擊仿真與識(shí)別方法研究
[Abstract]:High voltage transmission system is an important part of power transmission task in power system. Lightning strike is one of the main causes of transmission line insulation accidents, which is very harmful to power system. In order to prevent the frequent occurrence of lightning damage faults, the measures required in the field must be targeted, and different measures should be taken according to different lightning damage faults. Therefore, it is necessary to first analyze the type of lightning strike for fault treatment or lightning protection improvement of power system, otherwise, it is inevitable that there is no work and lightning accidents still occur frequently. Therefore, it is necessary to study the recognition of lightning strike type. In this paper, the 220kV transmission lines are simulated and analyzed, the overvoltage waveforms of different types of lightning strikes are obtained, the characteristic quantities are extracted, and the classification and recognition of lightning strikes are realized with intelligent classification method. PSCAD/EMTDC transient simulation software is used to simulate lightning stroke of 220kV transmission line. Considering the sectional wave impedance model of the tower, the lightning stroke of transmission line is modeled and analyzed. The simulation waveforms of five kinds of disturbances, such as common short circuit fault, inductive lightning strike, direct strike lightning disturbance, counterattack fault and wound failure, are obtained. The voltage waveform obtained by simulation is analyzed preliminarily, and the time-domain waveform difference of different types of lightning voltage signals is analyzed in combination with the mechanism of over-voltage generation. The overvoltage signal is analyzed by time-domain, frequency-domain and time-frequency joint analysis method, and the characteristic quantity reflecting the characteristics of the signal is obtained. Based on the time domain waveform, three characteristic variables, namely, the similarity of three-phase waveform W, the voltage integral eigenvalue 蠅 and the wave head volatility B, are extracted, and the characteristic quantity Q _ 1 / Q _ 2Q _ 3Q _ 3 / Q _ 4, which reflects frequency domain and time-frequency correlation, is extracted based on Hilbert-Huang transform and Hilbert time-frequency spectrum. Based on the teager energy operator, the characteristic quantities TG and TM, which reflect the variation characteristics and steepness of the wave head, are extracted. Considering the characteristics of different disturbances and the physical meaning of each characteristic quantity, the corresponding feature variables are selected for the recognition of each kind of disturbance, so as to improve the accuracy of recognition. The difference between lightning stroke and common short-circuit fault is mainly reflected in wave head fluctuation B and ratio Q _ 2 of high and low frequency energy, the wave head of lightning stroke is highly volatile and the content of high frequency component is high, and the inductive lightning strike appears in the three-phase conductor of transmission line at the same time. Therefore, the similarity of three-phase waveform W and Hilbert energy spectrum matrix Q _ 3 is high, which can distinguish induced lightning stroke from direct lightning stroke. The additional components of the voltage signal of lightning disturbance have positive and negative period alternation, so the voltage integral eigenvalue 蠅 can be used to identify the lightning disturbance. The difference between wound strike and counterattack is reflected in the characteristics of wave head and high frequency energy distribution. By calculating the maximum value T _ m of Teager energy value and whether or not the maximum value appears in the first extreme point, the characteristic quantity Q4 of high frequency energy distribution can be used to distinguish the striking back from the round strike. The maximum value of Teager energy and the maximum value of Teager energy reflect the steepness of the wave head and whether the maximum energy value appears in the first extreme point is calculated. In this paper, the basic concept, algorithm and kernel function selection of correlation vector machine are studied. The identification model of lightning strike type of transmission line is established by using multiple binary correlation vector machines. The extracted features are input into the classifier and the corresponding feature vectors are selected for each RVM. The recognition model is trained and tested by the simulation data. Finally, the intelligent identification of lightning strike type of transmission line is realized. A large number of simulation results show the effectiveness of the proposed model.
【學(xué)位授予單位】:華北電力大學(xué)
【學(xué)位級(jí)別】:碩士
【學(xué)位授予年份】:2014
【分類號(hào)】:TM863
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 王安定,葛耀中;模量變換技術(shù)在反應(yīng)故障分量的微機(jī)保護(hù)中的應(yīng)用研究[J];電力系統(tǒng)自動(dòng)化;1988年03期
2 郭寧明;覃劍;陳祥訓(xùn);;雷擊對行波故障測距的影響及識(shí)別[J];電力系統(tǒng)自動(dòng)化;2008年05期
3 段青;趙建國;馬艷;;基于稀疏貝葉斯學(xué)習(xí)的電力系統(tǒng)暫態(tài)穩(wěn)定評估[J];電力自動(dòng)化設(shè)備;2009年09期
4 葉會(huì)生,何俊佳,李化,林福昌;雷擊高壓直流線路桿塔時(shí)的過電壓和閃絡(luò)仿真研究[J];電網(wǎng)技術(shù);2005年21期
5 鄒貴彬;高厚磊;王明軍;朱峰;楊榮華;;一種雷電波侵入變電站的擾動(dòng)識(shí)別方法[J];電網(wǎng)技術(shù);2012年04期
6 丁美新,李慧峰,朱子述,肖登明;雷電流波形的數(shù)學(xué)模型及頻譜仿真[J];高電壓技術(shù);2002年06期
7 吳昊;肖先勇;;基于小波變換和行波理論的輸電線路雷擊定位[J];高電壓技術(shù);2007年01期
8 吳昊;肖先勇;鄧武軍;;輸電線行波測距中雷擊與短路故障的識(shí)別[J];高電壓技術(shù);2007年06期
9 陳家宏;張勤;馮萬興;方玉河;;中國電網(wǎng)雷電定位系統(tǒng)與雷電監(jiān)測網(wǎng)[J];高電壓技術(shù);2008年03期
10 肖先勇;李逢;鄧武軍;;雷擊與短路故障的S變換特征量識(shí)別方法[J];高電壓技術(shù);2009年04期
本文編號(hào):2196305
本文鏈接:http://www.sikaile.net/kejilunwen/dianlilw/2196305.html