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.
关键词
配电变压器/0.4kV开关柜/短路故障/继电保护动作/整定计算/对称分量法/绝缘防护/零序电流保护
Key words
distribution transformer/0.4 kV switch cabinet/short-circuit fault/relay protection action/setting calculation/symmetrical component method/insulation protection/zero-sequence current protection
维普
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