摘要
超/特高压输电线路发生电弧性故障时由于线路电容电感构成谐振回路会产生固有频率分量,利用并联电抗电流量的频率特征有助于实现线路保护的故障识别和重合闸的无故障判别。电弧性故障时先后经历一次电弧、二次电弧、恢复电压3个不同的物理阶段,各阶段分别由储能元件构成自振网络,由于各阶段自振网络结构的差异将产生不同的特征频率分量。通过相模变换实现三相耦合线路模量网络的固有特征频率的计算模型及特征分析,明确了利用并联电抗器电流的主要固有频率分量特征能够识别电弧性故障所处的物理阶段,为线路保护的故障识别和三相重合前的无故障判别提供有效的特征信息。最后PSCAD仿真分析结果表明,所分析的不同物理阶段的固有特征频率的相关理论的正确性,为下一步利用固有频率特征实现线路保护和重合闸方案提供了较好的理论基础。
The fault current contains the inherent frequencies components when the arc faults occur in UHV transmission lines with shunt reactors,which can offer effective fault information.In the primary arc,secondary arc and recovery voltage periods in the case of an arc fault with shunt reactors,the three free oscillation circuits are formed by the energy storage elements in the different periods,which will produce different inherent oscillation frequency components based on the different network.After phase-mode transformation,the free oscillation circuits in mode components are obtained and the inherent frequencies are captured,the characteristics of inherent frequency components are used to recognize the condition of a arc fault,offering a theoretical basis for the new protection principle based on inherent frequencies.PSCAD simulation results show the correctness of the theoretical analysis on the inherent,provides a good theoretical basis for the line protection and reclosing scheme by using characteristics of inherent frequency.
出处
《国外电子测量技术》
2016年第5期48-52,共5页
Foreign Electronic Measurement Technology
基金
西安工程大学博士启动基金(BS1018)项目资助
关键词
输电线路
并联电抗器
固有频率
相模变换
傅里叶变换
transmission line
shunt reactors
inherent frequency
phase-mode transformation
Fourier transform
