【作者】 郭健；

【导师】 徐建源； 李岩； 林莘；

【作者基本信息】 沈阳工业大学 ， 高电压与绝缘技术， 2005， 硕士

【摘要】 离相封闭母线在电厂中被用于连接各种发电机和电力变压器。随着发电机额定功率的增大,额定电流也越来越大。母线的工作状况与它所承载的电流和电压有关。母线电流对母线工作状态的影响涉及电磁学,热学和力学三种物理现象。母线的电压涉及到母线的绝缘问题。本文以大电流离相封闭母线为研究对象,以有限元理论为基础,分别对封闭母线做了电磁、温升、结构和绝缘的场域研究,在理论上建立了相应的数学模型,并编程进行实现,同时开发了封闭母线场域分析仿真软件,取得了一些具有理论意义和工程实际价值的结果。文中首先介绍了大电流母线的发展状况和对其进行场域研究的意义,并论述了国内外对它研究的概况及计算的方法。其次,建立了离相封闭母线电场、磁场、温度场以及结构分析的数学模型。对其进行耐压、短路电动力、温升和结构变形的分析计算。文章的最后编制了封闭母线场域分析的仿真软件,实现了参数化建模,加载,并从结果数据库中提炼出有价值的数据。文中使用了通用有限元软件ANSYS,采用了多场耦合的分析方法,并利用APDL语言编制了相应的耦合场计算程序。应用此种方法对磁场-结构耦合,磁场-温度场-流场耦合进行了分析。磁场-结构耦合首先分析系统的短路电流,母线在短路电流的作用下受到很大的电动力,然后将母线的短路电动力作为结构分析的载荷对母线进行应力变形分析。电流场-温度场-流场耦合首先分析母线工频稳态情况下的电流场损耗,然后将母线损耗作为温度场-流场分析的热源分析母线的温度以及母线内部空气流动的情况。其计算结果与理论计算结果进行了对比,误差在允许的范围内,证明本文采用的方法是正确可行的。离相封闭母线内部场强的分布,短路情况下母线的变形,以及母线的温升是考核封闭母线性能的重要指标。本文应用ANSYS的图象处理功能,很好的展示了封闭母线内部各种场的分布。本文的计算结果为离相封闭母线的设计和进一步研究提供了理论上的参考。更多还原

【Abstract】 Isolated Phase Bus (IPB) in power plants is used to connect all kinds of generator and power transformer. With the increasing of individual generator capacity, the rated current of generator is also increasing. IPB’s working performance is related to its current and voltage. The influence of IPB’s current to its working performance involves electromagnetics; calorifics and mechanics; IPB’s voltage affects its insulation. Many works on magnetic, temperature, structure and electric field of IPB, including theoretically mathematical formulation, algorithm, program, are mainly researched in this paper with FEM theory. at the same time IPB simulation analysis software is developed, and some valuable results to theory analysis and engineering design have been gained.In the first part of this paper, the development of IPB and significance of studying by field method are discussed. Secondly, algorithm of magnetic, temperature, structure and electric field on IPB are confirmed. Insulation, short circuit force, temperature rise and structure deformed are simulated analysis. In the end, IPB simulation analysis software is developed and can realize parameter modeling, loading and extract valuable data from result database file.The current software ANSYS is adopted in this paper, and a coupling analyses method is established too. By using APDL language, the program for coupling field calculation is made. The coupling analysis on the electromagnetic field and structure field and the coupling analysis on electromagnetic field, temperature field and fluid field are calculated by this method. The coupling on electromagnetic field and structure field begin with the analysis of short circuit current of system. Under the circumstances of short circuit, IPB receive prodigious force. The force used as load brings to structure analysis. The coupling on electromagnetic field, temperature field and fluid field begin with the energy loss of bus in the course of working. Then the loss is used as load of temperature field and fluid field. The results are compared withthe theory, and the error is in the allowable range. It testifies that the method adopted in this paper is feasible.IPB’s performance is examined by the distribution of electric field intensity; temperature rise and deformation result from short circuit force. In this paper, the distribution of all kinds of fields is vividly displayed. The results in this paper provide the theoretic reference gist and thoughts for the design and the further research on the IPB.更多还原