發(fā)布時間：2018-01-28 05:39

  本文關(guān)鍵詞： 輸電線路 人體 工頻電場 工頻磁場 電磁感應　出處：《山東大學》2015年碩士論文　論文類型：學位論文

【摘要】：近年來我國經(jīng)濟迅猛發(fā)展,目前的電網(wǎng)結(jié)構(gòu)及能源分布情況已經(jīng)不能滿足國民需求,建設遠距離、大容量、大電流的高壓輸電系統(tǒng)成為必然選擇。與此同時,高壓輸電系統(tǒng)帶來的環(huán)境問題也日益受到關(guān)注,主要表現(xiàn)在土地利用、工頻電場、工頻磁場、可聽噪聲等方面。本文研究超高壓交流輸電線路的電磁環(huán)境問題。本文主要從兩個方面對輸電線的電磁環(huán)境問題進行評估,即直接分析輸電線下地面上的電磁場和加入人體之后人體內(nèi)及周圍的電磁場。以有限元法為基礎,采用ANSOFT軟件進行仿真研究。首先,對交流輸電線路下地面上的電場和磁場的研究。根據(jù)實際線路情況,建立高壓輸電線的模型,分析輸電線的電磁場方程。將整個輸電線及周圍的環(huán)境參數(shù)進行處理,對其線下地面上的電場和磁場進行仿真分析,研究了線路對地距離、相間距離、單回路時的導線布置形式和雙回路時的相序布置方式等因素對電場強度和磁場強度的影響規(guī)律,提出了有效減小輸電線電磁場的方法。并以此為依據(jù),計算分析了人體的接觸電流和人體內(nèi)的電流大小。第二,采用二維方法對輸電線下人體內(nèi)及周圍的電磁場研究。根據(jù)人體的生理結(jié)構(gòu)特點,建立人體模型,將人體置于超高壓輸電線模型下,分析了加入人體之后地面上電場、電位等的變化。對人體內(nèi)的電場強度和磁場強度進行仿真。總結(jié)了影響人體內(nèi)電磁場強度的因素：輸電線對地高度、相間距離、排列方式、是否接地等。研究發(fā)現(xiàn),增加導線對地高度、合理布置導線方式如采用倒三角排列、減少相間距、架設架空屏蔽線等能有效減小輸電線下人體內(nèi)電場和磁場強度。最后,采用三維方法對輸電線下人體內(nèi)的電場的研究。以上均是采用二維方法進行的仿真研究,為了更接近實際人體情況和提高計算精度,進一步采用三維子模型進行研究。對輸電線及人體構(gòu)成整個區(qū)域中的某一區(qū)域進行分析,即將人體及周圍空氣單獨列出來,建立子模塊,通過之前二維有限元的方法求出子模塊中邊界(輸電線下某一位置)的電位值,然后賦值給子模塊,將子模塊單獨剖分。與前面用二維全模型的方法相比,可降低計算的復雜度,從全方位的角度分析典型輸電線下人體內(nèi)的電場。仿真結(jié)果表明,相同參數(shù)下采用三維子模型方法計算出的人體電場更能逼近實際人體電磁場的分布情況。
[Abstract]:In recent years, with the rapid economic development in China, the current power grid structure and energy distribution can no longer meet the needs of the people, the construction of long-distance, large-capacity, high-current high-voltage transmission system has become an inevitable choice. The environmental problems brought about by HV transmission system have been paid more and more attention, mainly in land use, power frequency electric field and power frequency magnetic field. In this paper, the electromagnetic environment of EHV AC transmission lines is studied. In this paper, the electromagnetic environment of transmission lines is evaluated from two aspects. That is, direct analysis of the electromagnetic field on the ground under the transmission line and the electromagnetic field in and around the human body after adding the human body. Based on the finite element method, ANSOFT software is used to carry out simulation research. The research of electric field and magnetic field on the ground under AC transmission line. According to the actual transmission line, the model of high-voltage transmission line is established. The electromagnetic field equation of transmission line is analyzed. The whole transmission line and its surrounding environmental parameters are treated, and the electric and magnetic fields on the ground below the line are simulated and analyzed, and the distance between the lines to the ground and the phase is studied. The influence law of wire arrangement form in single loop and phase sequence arrangement mode in double loop on electric field intensity and magnetic field intensity is put forward, and the effective method of reducing electromagnetic field of transmission line is put forward. The contact current of the human body and the current in the human body are calculated and analyzed. Secondly, the electromagnetic field in and around the human body under the transmission line is studied by two-dimensional method. According to the physiological characteristics of the human body, the human body model is established. The electric field on the ground was analyzed by placing the human body under the EHV transmission line model. The electric field intensity and magnetic field intensity in human body are simulated. The factors that affect the electric magnetic field intensity in human body are summarized: the height of transmission lines to the ground, the distance between phases, and the arrangement mode. Whether grounding or not. The study found that increasing the height of the wire to the ground, reasonable arrangement of conductors, such as the use of inverted triangular arrangement, reduce the phase spacing. Erecting overhead shielding lines can effectively reduce the electric field and magnetic field intensity under the transmission line. Finally, the three-dimensional method is used to study the electric field of the human body under the transmission line. In order to get closer to the actual human body and improve the accuracy of calculation, the three-dimensional submodel is used to study the transmission line and the human body constitute a region of the whole region. The human body and the surrounding air are listed separately, the sub-module is established, and the potential value of the boundary of the sub-module (a certain position under the transmission line) is calculated by the previous two-dimensional finite element method, and then assigned to the sub-module. Compared with the two-dimension full-model method, the calculation complexity can be reduced, and the electric field under the typical transmission line can be analyzed from an omni-directional angle. The simulation results show that. Under the same parameters, the human electric field calculated by using the three-dimensional submodel method can approach the distribution of the actual human electromagnetic field more effectively.
【學位授予單位】：山東大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：R594.8;TM75

【參考文獻】

相關(guān)博士學位論文 前1條

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本文編號：1469924