火电厂发电机失磁保护阻抗判据的探讨  

Discussion of thermal power plant generator resistance criterion for loss of excitation protection

作　　者：刘一丹[1] 张小易[2] 崔晓祥[1] 

机构地区：[1]江苏方天电力技术有限公司,江苏南京211102 [2]江苏省电力试验研究院有限公司,江苏南京211102

出　　处：《电力系统保护与控制》2010年第20期235-237,240,共4页Power System Protection and Control

摘　　要：介绍了火电厂失磁保护所应用阻抗判据的特点,分析失磁保护在机组进相运行时容易产生误动的原因,是由于励磁系统低励限制与失磁保护的整定配合不合理,低励限制曲线与阻抗圆有交叉。指出了国产部分失磁保护反向无功判据上存在的一些问题,这些无功判据并不能切掉阻抗圆的上半部分。利用机组容量曲线以及失磁保护阻抗圆与低励限制曲线的关系,提出了应用低励限制曲线来验证阻抗判据整定是否合理的方法。并利用机组进相试验的数据来进一步分析失磁保护能否误动。The criterion charactertistics of generator loss of excitation are introduced.The reason of loss excitation fault action during leading phase test is analyzed that underexciatation limited curve is crossed with excitation resistance round.This paper points out that reverse reactive power curve of some loss excitation protection made in China can not cut off the top of excitation resistance round.By using the relationship between underexcitation limited curve and unit capacity curve and loss excitation protection resistance round,a method is proposed to testify whether the calculation of loss excitation resistance is right or not through underexcitation limited curve.The leading test data is used for further analyzing whether the loss excitation protection can act rightly or not.

关 键 词：失磁保护 低励限制 阻抗 

分 类 号：TM773[电气工程—电力系统及自动化]