摘要
针对传统中低压系统三段式保护的保护范围小、动作时限长的缺点 ,提出了一种基于小波变换理论的全线相继速动保护新方案。该方案用 db小波提取故障后线路对侧断路器跳闸时本侧零序电流与负序电流之和产生的突变 ;并判断对侧断路器跳闸稳态后本侧零序和负序电流幅值是否小于定值 ,以区分本线路末端与下条线路出口的故障 ,作为本侧保护加速动作的依据。大量的
In the low-voltage power systems, the traditional line protections cannot cut off the fault of the whole line immediately. Aiming at this disadvantage, a new accelerated trip scheme based on wavelet transform is presented to improve the performance of the line protection. The new scheme uses the wavelet transform to efficiently detect the second abrupt changes of sequence currents, caused by the trip of the circuit breaker at the opposite side of a transmission line, as the evidence to accelerate the operation of the local breaker. Furthermore, lots of ATP simulations show that the new scheme can increase reliably and efficiently the response speed of relays in distribution system.
出处
《电力系统自动化》
EI
CSCD
北大核心
2003年第9期54-57,共4页
Automation of Electric Power Systems
