Event-based reasoning for short circuit diagnosis in power transmission networks

This document introduces an original, model-based technique for short circuit diagnosis in power transmission networks. The diagnostic task is viewed as a bottom-up interpretation process of available observations. Three different interpretation layers have been defined: local interpretation, global interpretation, and heuristic interpretation. This paper presents the first two layers. The local interpretation focuses on the behavior of single protection components that are distributed in the power network and operate when a short circuit occur. The global interpretation provides a global behavior of the protection apparatus by combining consistent local behaviors so that given interface constraints among components are met. Finally, the heuristic interpretation is meant both to shrink the cardinality of the global interpretation on the basis of application-dependent heuristic constraints, and to eventually localize the short circuit and possibly faulty protection components within the transmission network. The implementation of the proposed technique is under way. The resulting system will be tested by ENEL, the Italian electricity board.