临安山区输电线路覆冰预测及设计改进研究

发布时间：2018-05-31 20:48

本文选题：电力系统 + 输电线路覆冰　；参考：《华北电力大学》2015年硕士论文

【摘要】：近年来,受全球气候变暖影响,各类气象灾害更为频繁,造成的损失和影响日趋严重,破坏程度强、影响范围广,应对难度也越来越大。电力系统在规划设计及运行中如何应对电网覆冰带来的危害,成为一项非常重要又极具现实意义的研究课题。2008年中国南方雪灾后,许多科研院所、电力企业进行了线路覆冰方面的研究,但仅局限于大区域典型气象条件下的共性研究。山区微气象条件下输电线路覆冰设计的研究目前在国内外均属前沿课题,缺少相关的研究与应用。本论文研究的出发点与落脚点均为浙江省临安县天池山区这一确定的微地理微气象区域。首先研究了线路覆冰的形成机理和覆冰气象地理特征条件,在基于温度、风(速度和方向)、降雨量、云中液态水和相对湿度等多种气象因素下,提出了—种基本的覆冰模型。为准确获取临安山区重点线路安装的在线监测数据与气象站提供的气象数据验证了预测模型的科学性和精确性,从全局、地域、局部三个角度介绍了覆冰模型输入参数测量方法。同时重点分析了输电线路导线和结构的覆冰荷载数据的统计分析与建模,为下一步的架空输电线路设计和可靠性评估提供参考价值。应用临安地区输电线路在线监测设备保存的历史,应用模糊神经元网络理论方法建立天池山区覆冰预测模型。该模型的预测算法采用C语言开发,利用电力线路覆冰影响深度系数公式,对微气象参数影响因子由小到大进行排序,通过对有效数据的筛选,从而确定了神经网络输入层的构成分别是风速、风向、环境气温、环境湿度,使神经网络训练的数据更具有针对性,一定程度上提高了训练的快速性及精度。最后基于对未来极端气象条件预测的覆冰数据,应用还原论和反演论思想,构建复杂工况条件下多模态线路力学模型,推导相应部件应力求解方法,考虑部件长期运行强度影响因素及评判专家知识的不确定性,建立了强度模糊综合评价模型,验算了现有线路的力学结构的脆弱性,并据此提出新线路设计改进方案。进一步为输电线路覆冰设计研究提供量化分析工具,提高了临安地区输电线路抗冰保障综合技术能力和临安电网的安全运行水平。
[Abstract]:In recent years, affected by global warming, various kinds of meteorological disasters are more frequent, resulting in more and more serious losses and impacts, strong damage, wide range of impact, and more difficult to deal with. It has become a very important and practical research topic how to deal with the harm caused by the icing of power grid in the planning, design and operation of power system. After the snow disaster in southern China in 2008, many scientific research institutes, The electric power enterprise has carried on the research on the line icing, but it is limited to the common research under the typical meteorological conditions in the large area. The research on icing design of transmission lines under micrometeorological conditions in mountainous areas is currently a leading topic at home and abroad, and is lack of relevant research and application. The starting point and foothold of this paper are the microgeographical and micrometeorological area in Tianchi Mountain area of Lin'an County, Zhejiang Province. Firstly, the formation mechanism and the meteorological and geographical characteristics of the icing on the line are studied. Based on many meteorological factors, such as temperature, wind (velocity and direction), rainfall, liquid water in the cloud and relative humidity, a basic icing model is proposed. In order to obtain the on-line monitoring data and meteorological data provided by meteorological station in Linan Mountain area accurately, the prediction model is verified to be scientific and accurate. The method of measuring the input parameters of icing model is introduced from three local angles. At the same time, the statistical analysis and modeling of ice-covered load data of transmission line conductors and structures are analyzed in order to provide reference value for the design and reliability evaluation of overhead transmission lines in the next step. Based on the preservation history of transmission line on-line monitoring equipment in Lin'an area, a prediction model of icing in Tianchi mountainous area was established by using fuzzy neural network theory. The prediction algorithm of the model is developed by C language, and the influence factors of micrometeorological parameters are sorted by using the formula of the influence depth coefficient of icing on power lines, and the effective data are screened. It is determined that the input layer of neural network is composed of wind speed, wind direction, ambient temperature and humidity, which makes the data of neural network training more pertinent, and improves the training speed and precision to a certain extent. Finally, based on the ice-covered data of the prediction of the future extreme meteorological conditions, using reductionism and inversion theory, the multi-modal line mechanics model under complex working conditions is constructed, and the corresponding component stress solution method is deduced. Taking into account the influence factors of long-term operation strength of components and the uncertainty of expert knowledge, a fuzzy comprehensive evaluation model of strength is established, and the fragility of the mechanical structure of existing lines is checked and calculated. Based on this, a new route design improvement scheme is put forward. Furthermore, it provides a quantitative analysis tool for the study of icing design of transmission lines, and improves the comprehensive technical capability of anti-ice protection of transmission lines in Lin'an area and the level of safe operation of Linan power network.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TM752

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