中压开关柜内部电弧压力升计算--模型简化方法研究

中压开关柜内部电弧故障时有发生,其短时间释放出的巨大能量引起隔室内部压力迅速上升,对设备、建筑物以及工作人员的安全造成了严重威胁。基于零部件规则化和隔室等容积替代的简化原则,提出了开关柜复杂模型简化方法;利用CFD法计算了不同简化模型的压力分布规律,给出了模型最优简化方法;对SCM法与CFD法获得的计算结果进行了对比,分析了两者的差异。结果表明:采用规则化-等容积替代混合方式简化模型获得的结果与原始模型吻合较好,计算时间缩短了约54.39%;当泄压板打开后,隔室内部的压强分布差异较大,采用SCM法获得的结果误差较大,应采用CFD法进行求解。

Study on the Model Simpliflcation Method for the Calculation of Arc Pressure Rise in MV Switchgear

The arcing fault inside medium-voltage(MV) switchgear happened occasionally.The great energy is released in a short time in the switchgear,resulting in pressure rise rapidly,which caused a serious threat to the safety of the equipment,buildings and personnel.Based on the simplified principles such as regularization replacement of the parts and isovolumetric replacement of the compartment,the simplified methods for the switchgear complex model are proposed in the paper.The pressure distribution for the different simplified models are calculated by the CFD,and the best simplified method for the model is given.The results are calculated by the pressure rise standard calculation method(SCM) and CFD,and the difference of both is analyzed.The results show that the model obtained by combined with the regularization replacement of the parts and the isovolumetric replacement of the compartment can get similar results with the original model,and the computation time is reduced by 54.39%.After the pressure relief cover is open,the pressure distribution has a great difference in the compartment.The result error is big by using SMC,and the CFD should be adopted for the switchgear.