摘要
为了减少或消除重合于永久性故障给输电系统稳定运行所带来的不利影响,需要在断路器重合前预先判别故障类型是永久性还是瞬时性。根据超高压串补输电线路在单相瞬时性接地故障时,故障相恢复电压包含工频分量、接近于工频的分量以及低频分量,其功率谱有3条谱线;而永久性接地故障时,故障相恢复电压仅由工频分量、低频分量叠加而成,其功率谱有2条谱线。据此针对串补输电线路提出一种基于故障相恢复电压功率谱的单相接地故障识别方法,该方法利用故障相电压各分量功率谱的谱线分布来识别瞬时性故障和永久性故障,EMTP仿真验证了该方法的准确性和可行性。
In order to lessen or avoid the negative impact on the transmission system brought by reclosing on the perma-nent fault,it is essential to pre-determine the type of the fault (temporary or permanent) before the breaker recloses. When the single-phase temporary fault occurs at the EHV transmission lines with series capacitors,the recovery voltage of the fault phase composes of the power frequency component,approximate power frequency component, and its power spectrum of the recovery voltage possesses three spectral lines. The recovery voltage of the single-phase permanent fault,however,contains power frequency component and the low frequency component only,and its power spectrum possesses two spectral lines. On this basis,an identification method for temporary and permanent single-phase earth faults is established for the transmission lines with series capacitors. Simulation results show that the proposed method based on the power spectrum of the fault phase recovery voltage is accurate and feasible.
出处
《电网与清洁能源》
2014年第8期48-52,62,共6页
Power System and Clean Energy
关键词
超高压串补输电线路
瞬时性故障
永久性故障
功率谱
EHV series capacitor compensative transmission line
temporary fault
permanent fault
power spectrum
