摘要
转子绕组匝间短路是大型汽轮发电机时常发生的电气故障,故障恶化将严重影响发电机的正常安全运行。由于中国绝大多数的大型汽轮发电机不具备分支电流互感器的安装条件,基于定子不平衡电流有效值的故障监测原理应用受到了局限。为此,本文提出一种适用于无分支电流互感器的同步发电机转子绕组匝间短路故障监测方法,该方法依据故障前后励磁磁动势的变化形成故障监测判据。在对实际励磁磁动势的计算中,仅需用到发电机的定子漏抗参数及空载特性曲线,计算精度受发电机运行方式影响较小。通过一台1对极12kW隐极发电机模拟样机的实验验证了监测方法的有效性,该方法同样适用于转子两点接地保护。
The inter-turn short circuit of rotor windings is a normal electrical fault of a large turbine generator, and fault worsening will seriously hinder normal and safe operation of a generator. Since most of turbine generators in China are provided with no installation condition for a branch current transformer, application of the monitoring principle based on the stator unbalanced current RMS is limited. For solving the above problem, the paper provides a monitoring method of inter-turn short circuit of rotor windings in synchronous generators without stator branch current transformer. A fault monitoring criterion is formed according to change of excitation MMF before and after faults. In the calculation of real excitation MMF, only stator leakage reactance and no load characteristic curve of the generator are used, and influence upon calculation precision by the generator operating mode is smaller. Effectiveness of the monitoring method is verified through the experiment on a 12kW non-salient-pole synchronous generator with one pole. The method is also suitable for rotor two-point grounding fault protection.
出处
《电工技术学报》
EI
CSCD
北大核心
2014年第3期189-195,共7页
Transactions of China Electrotechnical Society
基金
国家自然科学基金(51307005)
中国博士后科学基金(2012M520155)
中央高校基本科研业务(2013JBM081)资助项目
关键词
汽轮发电机
励磁绕组
匝间短路
两点接地
监测
励磁磁动势
Turbine generator, field winding, inter-turn short circuit, two points to earth,monitoring, excitation MMF
