注入式定子接地保护在大型发电机组上的应用分析

在分析回路角度偏差、接地变参数、二次回路接线方法对注入式定子接地保护测量接地电阻精度的影响基础上,归纳角度补偿、阻抗补偿、电阻折算系数补偿的现场试验和调整方法,试验结果表明该注入式定子接地保护的测量精度能满足工程要求。通过分析保护动作范围及可靠性,提出合理的零序接地电流、动作电阻定值整定方法。

Application and analysis of stator grounding protection with voltage injection for large-sized generators

By analyzing the effects on measuring precision of earthing-resistance of stator grouding protection with voltage injection by circuit angle deviation,earthing transformer parameters and circuit connecting methods,the methods of field tests and adjusting about compensation of angle,resistance,resistance coefficient are summarized.The test results show that measuring precision is satisfactory.In the end,the methods of suitable zero-sequence current and action resistant fixed value setting are proposed by analyzing protection action range and reliability.