基于故障类型的同杆双回线故障分量提取算法

Novel Fault Components Extraction Approach for Double-circuit Transmission Lines on One Pole

针对传统的故障分量提取方法只能在故障后短时间内提取故障分量的缺点,提出了平行双回线基于故障类型在整个故障过程提取故障分量的新算法。该算法是在平行双回线路六序故障分量理论和故障边界条件及复合序网图的基础上,用同相量的负、零序电流和反相量的正、负、零序电流间接求得同相量正序电流的故障分量,进而合成得到每回线电流的相故障分量。该算法不受负荷电流和电网参数波动的影响。PSASP仿真表明了通过该算法得到的故障分量与实际故障分量相同,而且可以长时间提取。

Traditional fault component extraction approach can only satisfy the practical requirement in 2 or 3 cycles after fault inception. Based on the result of phase selection, a novel approach of fault component extraction is proposed for double-circuit transmission lines on one pole. The double-circuit transmission line is decomposed into the same directional component mode network and the circumfluent component mode network. The analysis demonstrates that the positive and negative sequence current distribution coefficients in the same directional component mode network coincide with that in the circumfluence component mode network. The proposed method can extract fault components correctly during the whole fault process and is free of influences of load and network parameters, etc. The digital simulation verifies the validity of the technique.