A graph theory approach for reliability analysis of phasor measurement units using frequency and duration technique

Abstract

Failure frequency and steady-state availability are two key indices for reliability analysis of phasor measurement units. Phasor measurement unit is the edifice of wide area measurement system and thus reliable operation is essential. Markov model is the general basis for evaluation of reliability indices, but it involves matrices of large dimension. This article describes the general purpose graphical approach for obtaining the two key reliability indices of phasor measurement units from flow graph based on Markov model. It is concerned with the calculation of availability, frequency and outage duration of phasor measurement units by module wise reliability analysis. This method itself is sufficient for sensitivity analysis of phasor measurement unit and helps in identifying the critical module within the phasor measurement unit.