750kV主变加装中性点小抗的研究及应用分析  

Research and Application Analysis of 750 kV Main Transformer Adding Neutral Small Reactance

作　　者：蔡晶[1] 沈星[2] 石海珍[1] 杨利民[1] 张楠[1] 

机构地区：[1]国网新疆电力公司检修公司,新疆乌鲁木齐830000 [2]国网电力科学研究院武汉南瑞有限责任公司,湖北武汉430074

出　　处：《电工电气》2015年第5期15-19,共5页Electrotechnics Electric

摘　　要：为降低乌北750 k V变电站220 k V侧的单相及两相接地(非对称)短路电流,使其小于三相短路电流,采用变压器中性点加装小抗的方法来实现该目标。研究了变压器中性点小抗的选择,以及变压器中性点加装小抗之后,对继电保护、绝缘配合及倒闸操作的影响。结果表明,当主变压器中性点经小抗接地时,接地短路电流幅值变小,保护装置的灵敏度变差,变电站的绝缘配合不受影响。To reduce the short-circuit current（asymmetric） of 220 kV side in Wubei 750 kV substation, making it reach the goal of less than three-phase short circuit current, the method of transformer adding neutral small reactance was adopted to reach the goal. This paper studied the choice of transformer neutral small reactance, and the influence of relay protection, insulation coordination and brake operation. The result shows that the grounding short-circuit current amplitude decreases, the sensitivity of protection device tails away, and the insulation coordination of the substation is not affected when the neutral point of main transformer via small reactance grounding.

关 键 词：短路电流 中性点小抗 继电保护 绝缘配合 倒闸操作 

分 类 号：TM406[电气工程—电器] TM862