Construction Method of Case-Base for Fault Restoration Support System in Secondary Power Systems

Abstract

We have already made clear that case-based reasoning (CBR) is very useful for the fault restoration support system in electrical power networks. This paper describes the construction method of case-base, adaptation and modification method of a case which is a fundamental process of CBR, and the results of evaluation.
The following points were clarified through the simulations of fault restoration under various conditions with electrical power networks of practical scale. (1) Construction method of case-base and the guide to the selection of cases which should be registered in case-base were made clear. Restoration plans which include many cases are registered in case-base. And cases which would take long computation time are additionally registered in case-base. In the application which requires high speed processing, such as fault restoration, there exists an optimum value in the total numbers of cases in case-base. (2) The function of load switching which is essential to perform adaptation and modification of a case flexibly was studied, and embedded it in our system. Inference power was augmented by the implementation of this function, optimum or sub-optimum solutions were obtained. Processing time with CBR is considerably shorter than other methods, and this feature is remarkable with complicated cases.