Introduction to Power System Reliability

Power system reliability studies usually focus on one of the following functional zones in the system: Generation system, Transmission system, Distribution system, Interconnected system or multi node system, Protection system, Industrial and commercial systems. Power system reliability indices, as well as the evaluative methods used to determine these indices, can be classified into two categories: predictive indices and empirical indices. Predictive indices are determined from information pertaining to component reliability and the manner in which components constitute the system. Empirical indices, on the other hand, are determined from direct observation, such as by collecting data at the location of interest. Another classification exists for power system reliability indices. This classifies indices into the categories: probability and expectation indices, frequency and duration indices, and severity indices. All these indices are probabilistic measures of system reliability.