基于模糊理论的多判据融合配电网故障选线研究

Research of fault line selection in distribution network based on multi-criteria fusion of fuzzy theory

在处理配电网单相接地故障时,仅基于单一故障特征的选线方法具有局限性,难以应对日益复杂的配电网工况。因此在对配电网单相接地故障特征分析的基础上,利用模糊理论将具有互补性的集合经验模态分解法、零序有功功率法和电流五次谐波法进行智能融合,设计了一种多判据融合的故障选线方法,并在Matlab/Simulink中搭建配电网单相接地故障模型,进行仿真验证。结果表明:该算法充分发挥各选线方法的优势,能适用于配电网中性点不接地系统及中性点经消弧线圈接地系统,在故障初相角及过渡电阻改变的情况下,仍能保持正确的选线率。

When dealing with single-phase ground faults in distribution networks,line selection methods based only on single fault characteristics have limitations and are difficult to deal with more complex distribution network conditions.Therefore,based on the analysis of the single-phase grounding fault characteristics,a multi-criterion fusion fault line selection method is designed by combining the complementary ensemble empirical mode decomposition method,zero-sequence active power method,and fifth harmonic method through intelligent fusion based on fuzzy theory.Then a single-phase grounding fault model of the distribution network is established in Matlab/Simulink for simulation verification.The experimental results show that the algorithm fully utilizes the advantages of each line selection method,and can be applied to the distribution network neutral point ground-free system and neutral point grounding system via the arc cancellation coil.The method can still keep a correct line selection rate even if the initial phase angle of the fault and the transition resistance are changed.