摘要
提高变压器差动保护的安全性和灵敏性一直是学术界关注的热点问题。故障分量差动保护由于灵敏度更高,已经在实际运行中得到广泛应用,但是该保护(包括全电流差动保护)判据由于固定了动作特性曲线的有关参数,导致不能同时提高保护的安全性和灵敏度。文中提出了一种自适应比率差动保护的新判据,该判据可以根据系统运行状态来调节动作特性各参数,能更可靠区分区内、区外故障,相比传统的故障分量差动保护具有更高的灵敏度和安全性。特高压变压器的动模试验验证了该保护判据的有效性。最后,对电流互感器局部暂态饱和情况下该判据的防误动能力进行了分析。
It has been the focus of study on improving the security and sensitivity of transformer differential protection recently.Because of its higher sensitivity,differential protection based on fault component has been widely used in practice.But traditional criterion of differential protection is impossible to improve both security and sensitivity of protection simultaneously with setting fixed characteristic curve.A new criterion for adaptive protection that can adjust the parameters of protection characteristic according to operation modes of power grid is proposed.It can reliably discriminate fault inside or outside region and has higher sensitivity and security than that of traditional differential protection based on fault component.The feasibility and superiority of this method are proved by dynamic simulation test on an ultra-high voltage transformer.Finally,the ability of the new criterion to avoid mal-operation under the circumstances of current transformer with partial transient saturation is analyzed.
出处
《电力系统自动化》
EI
CSCD
北大核心
2011年第17期86-91,115,共7页
Automation of Electric Power Systems
基金
国家电网公司科技项目~~
关键词
变压器差动保护
故障分量
自适应
安全性
灵敏度
transformer differential protection
fault component
adaptive protection
security
sensitivity
