Analysis of Short-circuit Fault on the 0.4 kV Side of a Distribution Transformer
In an incident of short-circuit fault occurring at a 35 kV substation,the relay protection does not act normally and the 0.4 kV switch cabinet is burnt out.By calling the fault recording and adopting the symmetrical component method with one-time equipment inspection,the fault process and protection action are analyzed.On this basis,optimization suggestions are proposed,including enhancing the insulation protection,increasing the spacing,and shortening the duration of the protective action of the bare bar copper in the 0.4 kV switch cabinet,so as to ensure step-by-step coordination of the protection on both sides of the distribution transformer.
distribution transformer0.4 kV switch cabinetshort-circuit faultrelay protection actionsetting calculationsymmetrical component methodinsulation protectionzero-sequence current protection
万方数据
维普
