【作者】 王伟；

【导师】 苑舜； 蔡志远；

【作者基本信息】 沈阳工业大学 ， 电机与电器， 2011， 硕士

【摘要】 12kV高压开关柜广泛应用于城市供电和配电系统中,但由于设计、制造、安装和运行维护等方面存在的问题,事故率比较高。导致故障的原因也有很多,其中内部电弧故障是一种频发性的、灾难性的严重的故障,将会给设备及人身安全带来危害。对开关柜的内部燃弧进行试验及仿真分析,全面掌握内部电弧故障的发展过程,是预防和控制内部燃弧故障的有效途径。本文首先简要介绍了开关柜内部燃弧的基本理论,如燃弧的故障特性、作用机理等,从而确定了开关柜内部燃弧仿真计算的重要意义。并且,对比分析了开关柜的柜体结构,选择了KYN28-12(Z)作为本文所要进行计算的柜型。在试验站对此开关柜进行了内部燃弧试验,试验合格。其次,对开关柜内部燃弧进行仿真计算。在仿真的过程中,采用了GAMBIT前处理器建立三维的计算模型,运用FLUENT软件进行求解。在求解的过程中,分别改变气室泄压盖的长度、深度及电弧加载位置等参数进行了数值仿真。仿真结果表明：气室泄压盖的长度和深度对压力变化过程带来的影响比电弧的加载位置带来的影响大些。再次,在对开关柜内部燃弧进行仿真计算的基础上,运用第一强度理论对开关柜的柜体强度进行了校核计算。校核的结果是开关柜的柜体满足柜体强度的要求,能够承受开关柜内部燃弧时带来的巨大冲击力。最后,针对燃弧仿真过程中柜门局部受到很大冲击力的情况,对开关柜的柜门进行强度优化。改变开关柜柜门的形状,比较分析各种不同形状柜门在燃弧过程中受到的冲击力,使柜体受到的冲击力最小。将优化前后结果进行对比分析,得出优化结论。为开关柜的设计提供了理论基础。更多还原

【Abstract】 12kV high voltage switchgear are widely used in urban power supply and distribution system, but due to the problem of design, manufacture, installation, operation and maintenance and other aspects, it has a relatively high accident rate, and there are lots of reasons leading to faults. The internal arcing fault is a frequent and a catastrophic fault, it will brought hazards to the equipment and personal safety. For the switchgear, have an internal arcing experiment and simulation analysis, completely grasp the development of the internal arcing fault is an effective way to prevent and control the internal arcing faults.In this research, the basic theory of the internal arcing in switchgear is briefly introduced, such as arc fault characteristics, mechanism and so on, which determine the significance of the internal arcing simulation calculation in the switchgear. The cabinet structure of the switchgear is analyzed comparatively, and KYN28-12 (Z) switchgear is selected as calculated cabinet type in this research. The internal arcing experiment in switchgear is carried out at the experiment station, and it passed.Secondly, internal arcing in switchgear is simulated. In the simulation process, using the GAMBIT pre-processor to establish three-dimensional computational model, and the model is solved by FLUENT software. In the solution process, the parameters are changed respectively, such as the length and depth of pressure relief cover, and the loading position of arc of the air chamber. Simulation results shows that the length and depth of air chamber affect pressure change process bigger than the arc loading position.And then, based on the simulation calculation of internal arcing in the switchgear, cabinet strength of the switchgear was checked by using the first strength theory. The results shows that the switchgear’s cabinet can meet the requirements of the cabinet strength, and it can withstand the tremendous impact of internal arcing.Finally, in the simulation process local position of the door suffer impact severely, switchgear s door strength should be optimized. the shape of the switchgear’s cabinet door is changed, in the arc process the doors with different shapes that suffer the impact by internal arcing are analyzed respectively, and make the impact force to the cabinet is smallest. The results before and after the optimization are comparative analyzed, the optimal conclusion. The research provides a theoretical basis for the switchgear design.更多还原