【作者】 姜志超；

【导师】 赵学增；

【作者基本信息】 哈尔滨工业大学 ， 机械电子工程， 2009， 硕士

【摘要】 超高压输电线自投入运行以来,已逐渐成为我国电力系统的主干网络。随之而来,超高压输电线路产生的电磁污染对沿线附近居民以及设备的影响引起了社会各方面的关注,越来越多的研究表明了这种污染的危害性。所以设计输电线路时应尽量减少的电磁污染,减少占地走廊面积。研究输电线路周围电磁场的大小对输电线路的设计有着重要的意义。此外,春检或输电线出现故障时,检修人员检修线路前必须进行验电、以保证人身安全。随着电网运行电压等级的提高,输电线距离地面越来越高,传统的接触式验电器已经很难适应实际需要,因此开发非接触式验电设备将是一个重要的研究方向。超高压输电线运行时,其周围空间存在工频电场,不同运行状态下电场分布规律,可由此来判断超高压电运行状态。为了对超高压输电线周围电场建模仿真,对超高压输电线路进行了一些必要的假设和简化处理,基于模拟电荷法建立了超高压输电线路二维电场的数学模型,该模型适合于空旷地带。用Matlab对算例进行仿真分析,总结了工频电场的基本分布规律。然后分析了不同条件下超高压输电输电线周围电场分布规律,结合环境评估标准,探讨了减小工频电场分布的措施,得到一些有益的结论。随后分析了超高压电缺相后场强分布规律并总结特点,提出根据该特点用于完成对输电线状态的分析。根据超高压输电线大电流的特点,在一些简化条件的基础上,基于模拟电流法建立了超高压输电线路周围二维磁场的数学模型。通过Matlab仿真分析,得出了超高压输电线路的工频磁场基本规律,进而分析了不同条件影响下的超高压输电线周围工频磁场分布规律。提出一种基于单片机的超高压输电线下工频电场检测系统。该系统可以对空旷地带超高压输电线下工频电场检测并显示,而且能够判断超高压线通断电状态,通过指示灯显示。最后通过对超高压输电线路周围场强实测分布验证了所建立超高压输电线周围电磁场强度模型的应用可行性,通过一些实验室试验对检测系统中重要部分加以测试分析,系统基本达到了设计要求。更多还原

【Abstract】 Since put into operation, the EHV transmission lines have gradually becomethe backbone network in electric power system in China. Thereupon the influenceon residents and equipment nearby from the electromagnetic pollution produced bythe EHV transmission lines has attracted the attention of various circles of societyand more and more studies indicate perniciousness of the pollution. So thetransmission lines should be designed to minimize electromagnetic pollution andreduce the transmission lines corridor area. Studying the electromagnetic fieldsurrounding the transmission lines has important significance for transmission linedesign.In addition, maintainers must check whether the lines are still running beforeoverhauling the lines to ensure personal safety in the spring inspection or powerfailure. With the voltage levels of power network in operation increase, the distancebetween transmission line and ground higher and higher, traditional contactingelectroscope has struggled to adapt to actual needs, thus developing electricequipment for non-contact examination is an important research direction. Whenthe EHV transmission lines are running, frequency electric field permeate the spacearound, we can judge the running state of the lines from the distribution rule underdifferent conditions.To establish modeling and simulation of electric field around the EHVtransmission lines, some necessary hypothesis and simplified handling charge arecarried out, and the mathematical model of two-dimensional electric field aroundthe EHV transmission lines is established based on the charge simulation method,and the model is suitable for open field. I summarize the basic distribution rule ofthe frequency electric field through doing simulation analysis of examples byMatlab. Then I analyze the electric field distributions around the EHV transmissionlines under different conditions, to combine environmental assessment standards,some measures are discussed to decrease the distribution of frequency electric fieldand some useful conclusions are obtained. Then I analyzed the electric fielddistributions around the EHV transmission lines without part of three phases andsummarized the characteristics and proposed a method to complete analysis for thestate of transmission lines according to the characteristics.According to the characteristics of large current about EHV transmission lines in some simplified conditions, the mathematical model of two-dimensionalmagnetic field around the EHV transmission lines is established on the basis ofcurrent simulation method. Through Matlab simulation analysis, I arrived at thebasic law of frequency magnetic field and analyzed frequency magnetic fielddistribution rule around EHV transmission lines on the influence of differentconditions.A frequency electric field detection system based on single chip was putforward for EHV transmission lines. This system can detect and display thefrequency electric field under EHV transmission lines in an open field, and be ableto judge the state of EHV lines through power and show the result by indicator light.Finally application feasibility of the model established for electromagneticfield intensity around EHV transmission lines was verified through actualmeasurement of the field intensity distribution around transmission lines, someimportant components of the system were tested and analyzed in some laboratorytests, and basically the system has achieved the design requirements.更多还原