基于模糊信息检索的变压器差动保护

Power transformer differential protection based on fuzzy information retrieval

针对目前变压器差动保护存在的不足,在对差流形成的原因及其各自的特征进行深入分析的基础上,将信息检索和模糊数学的有关理论应用于变压器励磁涌流和故障电流的判别,提出了一种基于模糊信息检索识别变压器故障的新判据。仿真试验结果表明:所提方法能够使各判据优势互补,克服了传统保护中的某些不足,改善了变压器保护的性能;利用信息检索法不仅能识别出涌流,而且还可以比较明确地区分出是属于何种工况,便于对涌流的特性进行更深入的分析研究;该方法无须设定判据的权重,减少了人为因素的影响,从而提高了判据的可靠性。

Due to the disadvantages of the existing transformer differential protection,a new criterion of identifying transformer fault based on fuzzy information retrieval is proposed through an in-depth analysis of the cause of differential current and its characteristics,and by applying information retrieval and fuzzy math to the identification of transformer inrush current and fault current.It is proved by simulations that the method mentioned in this paper can improve the performance of transformer protection,can clearly find out the type of working condition which helps to deeply analyze the characteristics of the inrush current and can eliminate man made effects so that the reliability of the criterion is improved.