高压盆式绝缘子电场优化研究

发布时间：2018-03-16 13:41

本文选题：盆式绝缘子　切入点：电场优化　出处：《上海电力学院》2017年硕士论文　论文类型：学位论文

【摘要】：GIS由于具有占地面积小、结构紧凑、可靠、安全、灵活等优点,近年来在超高压和特高压变电站中得到了广泛的应用。GIS中的盆式绝缘子起着支撑导体、隔离气室和电气绝缘的重要作用。当绝缘子的沿面场强超过起晕场强时,将会产生电晕放电。实践经验表明,在盆式绝缘子上安装均压环和屏蔽罩可有效改善绝缘子沿面电场和电位分布。本文运用有限元分析软件Ansoft对盆式绝缘子建立模型,进行电场计算,并以此确定盆式绝缘子均压环和屏蔽罩结构优化目标;在此基础上,引入神经网络算法,利用BP神经网络拟合了均压环和屏蔽罩各结构参数与优化目标之间的关系,对均压环和屏蔽罩的结构参数进行了优化设计,得到最优结构参数,克服了传统穷举法计算量大、消耗时间长的问题。实验表明,在盆式绝缘子上安装优化过的均压环和屏蔽罩可以大大降低盆式绝缘子沿面最大电场强度,有效改善盆式绝缘子沿面电场不均匀程度。本文的研究工作主要包括以下几部分:(1)介绍了课题的研究现状以及电磁场和有限元基本原理以及神经网络算法,详细地介绍了BP神经网络算法的模型、工作原理以及工作流程,为后续章节均压环和屏蔽罩结构参数的优化设计提供理论基础。(2)在盆式绝缘子的设计过程中,安装合适的均压环有助于改善电位和场强分布,减少电晕以及击穿的可能性,增强盆式绝缘子的电气性能。利用BP神经网络算法,以盆式绝缘子沿面最大场强和均压环表面最大场强作为目标函数,对均压环的结构参数进行优化设计。(3)在盆式绝缘子的设计过程中,在盆式绝缘子上安装屏蔽罩可有效改善绝缘子沿面电场和电位分布。盆式绝缘子的沿面电场受屏蔽罩的形状、尺寸和位置等影响,因此安装合适的屏蔽罩可以有效改善盆式绝缘子沿面电场和电位,减少电晕和闪络现象。利用BP神经网络算法,以盆式绝缘子沿面最大场强和屏蔽罩表面最大场强作为目标函数,对屏蔽罩的结构参数进行优化设计。(4)在盆式绝缘子的设计过程中,针对在盆式绝缘子上安装外法兰对其电场强度有无影响的质疑,进行建模分析计算;同时,对盆式绝缘子内法兰与树脂间气隙进行建模计算,从而得到优化设计。
[Abstract]:Due to its small area, compact structure, reliability, safety and flexibility, GIS has been widely used in UHV and UHV substations in recent years. The important role of isolating gas chamber and electrical insulation. Corona discharge will occur when the plane field strength of insulator exceeds the intensity of halo field. The distribution of electric field and potential along the surface of the insulator can be effectively improved by installing the equalizing ring and shielding cover on the basin insulator. In this paper, the finite element analysis software Ansoft is used to establish the model of the basin insulator and calculate the electric field. On the basis of this, the optimization target of the structure of the basin insulator equal pressure ring and shield cover is determined, and on this basis, the neural network algorithm is introduced to fit the relationship between the structural parameters of the uniform pressure loop and the shield cover and the optimized target, and the BP neural network is used to fit the relationship between the structure parameters of the uniform pressure loop and the shield cover. The structural parameters of the uniform pressure loop and the shield are optimized, and the optimal structural parameters are obtained. The problems of the traditional exhaustive method are overcome, such as the large calculation amount and the long time consumption. The experimental results show that, The maximum electric field strength along the surface of the basin insulator can be greatly reduced by installing the optimized equalizing ring and shielding cover on the basin insulator. The research work of this paper mainly includes the following parts: 1) introduce the research status of the subject, electromagnetic field, basic principle of finite element and neural network algorithm. The model, working principle and working flow of BP neural network algorithm are introduced in detail, which provides a theoretical basis for the optimization design of the structural parameters of the uniform pressure ring and shield cover in the subsequent chapters in the design process of the basin insulator. Installing suitable equalizing ring can improve the distribution of potential and field strength, reduce the possibility of corona and breakdown, and enhance the electrical performance of basin insulator. Taking the maximum field strength along the plane of the basin insulator and the maximum field strength on the surface of the uniform pressure ring as the objective function, the optimum design of the structural parameters of the uniform pressure ring is carried out in the design process of the basin insulator. Installing a shield on a basin insulator can effectively improve the electric field and potential distribution along the surface of the insulator. The electric field along the surface of the basin insulator is affected by the shape, size and position of the shield. Therefore, installing a suitable shield can effectively improve the electric field and potential along the surface of the basin insulator and reduce the corona and flashover phenomena. Taking the maximum field strength along the surface of the basin insulator and the maximum field strength on the shield surface as the objective function, the structural parameters of the shield are optimized in the design process of the basin insulator. In view of the doubt that the external flange installed on the basin insulator has an effect on the electric field strength, the modeling analysis and calculation are carried out, and the air gap between the flange and the resin inside the basin insulator is modeled and calculated, and the optimum design is obtained.
【学位授予单位】：上海电力学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM216

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