Dealing with uncertainties in the fault diagnosis of power systems

This paper presents a fuzzy-expert system for the diagnosis of various faul ts that may occur in power systems. Various methodologies to deal with unce rtainty in diagnostic reasoning processes, together with the fuzzy reasonin g method are discussed. By using the possibility measure, decision making u nder uncertainty for the diagnosis of fault sections is easily manipulated, and identifying the simultaneous multiple faults are treated in the same p rocess. The methodology to identify false-operations or non-operations of p rotective devices are also discussed. As the system applies topology based knowledge representation, this system can be generally applied to other pow er systems without modifying the rule-base. The case studies showed a promi sing result.