【作者】 石玉侠；

【导师】 刘晓明；

【作者基本信息】 沈阳工业大学 ， 电气工程， 2006， 硕士

【摘要】 随着电力系统不断发展,系统容量不断提高,真空断路器向着大容量、小型化、高可靠性、高绝缘能力的研究方向发展。而基于电场的数值求解是目前研究绝缘问题的重要手段。在常用数值求解方法中,有限元法以其通用性强,适用于结构复杂、多重介质复杂场域求解,且求解精度高等优点而被广泛用于电器电场的数值求解。近年来,随着计算机技术的发展,现代优化新思想被广泛应用于真空断路器灭弧室结构设计以及小型化研究中。 基于上述分析,本文以中压真空灭弧室为研究对象,以商用有限元软件包ANSYS为数值求解支撑,研究不同结构真空断路器灭弧室内部电场分布;研究真空灭弧室中触头结构以及悬浮电极结构对全场域电场的影响机理;全场域最大场强分布;无限场域中悬浮电极电位随开距的动态变化规律;灭弧室内动、静触头沿面场强分布等。并在上述电场数值分析基础上,以真空灭弧室实际产品结构为研究对象,采用ANSYS软件包中的零阶优化方法,以触头结构和悬浮电极型面结构参数为优化设计变量,以改善全场域电场分布为优化目标函数,以循环迭代次数为停止准则,在断路器不同开距下全场域电场数值分析基础上进行电场逆问题求解,实现真空灭弧室内部结构综合优化设计。最后将优化结果与产品结构进行对比分析,证明了优化设计的可行性和有效性。在上述理论研究基础上,在金属封闭铠装型移开式开关设备内对12kV真空灭弧室进行试验研究,包括:峰值耐受电流和短时耐受电流、凝露与污秽试验、机械寿命试验、温升试验、短路开断及关合试验。为中高压真空断路器灭弧室结构优化设计及新产品研发提供了理论基础。更多还原

【Abstract】 With the development of the electric power system and the increase of the power capacity, there is a novel development tendency to realize the miniaturization of the vacuum circuit breaker with high capacity and insulation performance. It is very necessity to study the insulation performance based on the numerical analyses of the electric field. Among the numerical simulation methods, the finite element method (FEM) is widely to solve the electric field with complex structure and multi-dielectric medium with high precision. Recently, with the development of the computer technology, the modern optimization strategy has been effectively employed for optimizing the vacuum interrupter (VI).Based on the above analyses, the electric field of medium voltage VI has been numerically simulated using FEM. Moreover, the distribution of electric field for different structures has been obtained. In this thesis, the effect of the structure of the movable and fixed contact on the distribution of the electric field has been studied. And the mechanism of the influence of the floating electrode on the field strength has been investigated. Furthermore the distribution of the electric field along the movable and fixed contact has been obtained and figured out. From the comparison and analyses of the distribution of the electric field in the whole domain, the inverse computation and the optimization of the VI has been performed. By using the zero-rank optimizing method, the comprehensive optimization of the movable contact, the fixed contact and the floating electrode have been realized. In optimizing, the minimum of the electric field strength is considered as the objective function, and the contour of the movable contact, the fixed contact and the floating electrode are regarded as the optimized variable, the maximum iteration times is the stop criteria. The feasibility and validity of the optimized strategy has been verified with the comparison of the optimized results and the actual cases. Besides the numerical simulation, the corresponding tests have been performed, such as, the peak value duration current, short term duration current, dirtiness, mechanical service life, and the temperature rise test. And the theoretical foundation for optimizing and developing the VI has been provided.更多还原