本文選題：電暈起始場強 + 合成電場�。� 參考：《重慶大學》2014年碩士論文

【摘要】：發(fā)展具有輸電容量大、輸電距離遠等特點的特高壓直流輸電是我國目前的國情需要，但特高壓直流輸電線路電暈效應造成的線下電磁環(huán)境改變、無線電干擾和可聽噪聲等問題無法回避。目前直流線路電暈起始特性的研究主要集中在電暈起始場強和電暈起始電壓兩方面，對直流線路電暈起始特性的計算一般忽略正負極導線起暈機理的差異。直流線下合成電場的水平是線下電磁環(huán)境的重要指標，而對線下合成電場的研究大多以線路結構參數(shù)對合成電場的影響為主，隨著特高壓直流輸電工程建設的快速發(fā)展，促使我們需要考慮到直流線路經(jīng)過房屋建筑物與鄰近人體等復雜環(huán)境的合成電場分布情況。 本文從直流線路正負極導線不同的起暈機理出發(fā)，以典型的特高壓直流線路電暈起始場強和鄰近房屋與人體時的合成電場為研究重點，主要開展了如下的工作： 首先，闡述正負極電暈自持放電起暈判據(jù)與直流線下合成電場形成機理，推導了利用模擬電荷法對導線表面空間電場與標稱電場計算過程，建立基于Deutsch假設的合成電場計算模型，為研究線路起暈場強和線下合成電場奠定基礎。 其次，分別提出正負極直流電暈自持發(fā)展的條件，建立以光電效應電子輻射機理為依據(jù)的正負極直流導線電暈起始計算模型，分別討論了子導線半徑、導線對地高度、分裂間距、導線極間距和不同絞線結構等參數(shù)對典型雙極直流線路各極子導線電暈起始場強和電暈起始導線外加電壓的影響，從工程上分析了減輕線路電暈效應的方法。并通過對同塔雙回線路不同極性排布方式時起暈場強和電暈起始電壓的比較，得出-+/-+排布方式線路的電暈程度最低。 再次，以兩種不同的房屋模型為例，建立特高壓直流輸電線路鄰近建筑物時合成電場的計算模型，開發(fā)直流線路鄰近房屋附近合成電場的三維計算方法，比較了三維與二維計算結果的差異。分析了鄰近房屋的合成電場分布受不同房屋結構、房屋高度、房屋與線路中心距離等因素的影響，對比同塔雙回不同排布方式下鄰近房屋合成電場的計算結果，，提出線路下方房屋的高度限制以及房屋與線路中心的規(guī)避距離。 最后，探究了人體位于特高壓雙極直流線路下方的合成電場的分布問題。選取合理的人體簡化模型參數(shù)，在人體模型直接接地的條件下，繪制人體模型分別位于正極與負極導線兩側(cè)時人體附近合成電場分布的等值線圖。討論并分析了人體不同站位方式、不同身高和與線路中心不同距離對人體附近合成電場的畸變作用。
[Abstract]:It is necessary to develop UHV HVDC with large transmission capacity and long transmission distance, but the off-line electromagnetic environment is changed due to corona effect of UHVDC transmission line. Problems such as radio interference and audible noise cannot be avoided. At present, the research on the corona initiation characteristics of DC lines is mainly focused on the two aspects of the corona starting field strength and the corona starting voltage. The difference of the corona initiation mechanism of the positive and negative conductors is generally neglected in the calculation of the corona initiation characteristics of the DC lines. The level of the synthetic electric field under DC line is an important index of the electromagnetic environment under the line, but the research of the synthetic electric field under the line is mostly based on the influence of the line structure parameters on the synthetic electric field. With the rapid development of the UHV HVDC project construction, the level of the synthetic electric field below the DC line is very important. It is necessary to consider the distribution of electric field in complex environments such as buildings and adjacent human bodies. Based on the different halo generation mechanism of the positive and negative electrode conductors of DC lines, this paper focuses on the initial field intensity of corona of typical UHV DC lines and the synthetic electric field when the buildings are adjacent to the human body. The main work is as follows: First of all, the criteria of self-sustained discharge of positive and negative corona and the formation mechanism of synthetic electric field under DC line are expounded, and the calculation process of space electric field and nominal electric field on conductor surface using simulated charge method is deduced. The calculation model of synthetic electric field based on Deutsch hypothesis is established, which lays a foundation for studying the intensity of line halo field and the above line synthetic electric field. Secondly, the conditions of self-sustaining development of positive and negative direct current corona are put forward, and the calculation model of corona initiation of positive and negative direct current conductors based on the mechanism of photoelectron radiation is established, and the radius of sub-conductors and the height of conductors to the ground are discussed respectively. The effects of the parameters such as split spacing, wire pole spacing and different strands structure on the initial field strength of corona and the external voltage of the corona starting conductor in typical bipolar DC lines are discussed. The methods to reduce the corona effect are analyzed in engineering. By comparing the intensity of corona field and the initial voltage of corona in different polarity arrangement mode of double-circuit line of the same tower, it is concluded that the corona degree of -r-arrangement line is the lowest. Thirdly, taking two different building models as an example, the calculation model of composite electric field in buildings adjacent to UHVDC transmission lines is established, and the three-dimensional calculation method of composite electric field near buildings is developed. The difference between three-dimensional and two-dimensional calculation results is compared. The composite electric field distribution of adjacent buildings is analyzed, which is influenced by different building structure, building height, and distance between the building and the center of the line, and the calculation results of the composite electric field of the adjacent buildings under different arrangement modes of the same tower are compared. The height limit of the house under the line and the circumvention distance between the house and the center of the line are proposed. Finally, the distribution of synthetic electric field under UHV bipolar DC line is investigated. Selecting reasonable parameters of human body simplified model, under the condition that the human body model is directly grounded, the isoline diagram of the synthetic electric field distribution near the human body is drawn when the human body model is located on both sides of the positive and negative electrode conductors, respectively. This paper discusses and analyzes the distortion of synthetic electric field near human body by different stations, different height and distance from the center of the line.
【學位授予單位】：重慶大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TM721.1

【參考文獻】

相關期刊論文 前10條

1 范建斌;李中新;谷琛;殷禹;宿志一;;直流電壓下導線起暈電壓計算方法[J];電工技術學報;2008年10期

2 劉有為,李繼紅,李斌;空氣密度和濕度對導線電暈特性的影響[J];電網(wǎng)技術;1990年04期

3 李順元;±500千伏直流輸電線路電場效應及人體感受的試驗研究[J];電網(wǎng)技術;1991年01期

4 楊勇;陸家榆;雷銀照;;同走廊雙回直流線路地面合成電場計算[J];電網(wǎng)技術;2009年19期

5 胡琴;舒立春;蔣興良;孫才新;袁前飛;楊占剛;;大氣參數(shù)對導線交流起暈電壓的影響及校正[J];電網(wǎng)技術;2010年11期

6 干U喸

本文編號：1824234