Fault Diagnosis Based on Cluster Analysis Theory in Wide Area Backup Protection System

In wide area backup protection of electric power systems, the prerequisite of protection device´s accurate, fast and reliable performance is its corresponding fault type and fault location can be discriminated quickly and defined exactly. In our researches, global information has been introduced into the backup protection system. By analyzing and computing real-time PMU measurements, basing on cluster analysis theory, we are using mainly hierarchical cluster analysis technology to seek after for the statistical laws of electrical quantities´ marked changes. Then we carry out fast and exact identification of faulty components and faulty sections, and finally accomplish fault isolation. Multivariate statistical analysis theory is an efficient theory that can resolve different kinds of complex problems. It has been applied successfully in many researches of various fields, such as geology, weather, hydrology, iatrology, industry, agriculture, and economy, etc. In the study of electric power systems, multivariate statistical analysis theory must also have a good prospect of application.