Stochastic Network Reduction Technique for Calculations of Electrical Power System Structural Reliability

Abstract

This paper considers calculation of structural reliability indices (SRI) for electrical power system (EPS), when "cutoff" failures are taken into account. Calculations are based on "exclusion-renewal" technique. In this paper, the design scheme slightly differs from the electrical scheme. Stochastic network reduction (SNR) technique is considered as the main tool for network reduction. SNR also accounts for directional elements, which have different SRI in forward and backward direction of power flow. The paper shows that difference in resulting SRI of diverse software solutions (SS) arise from different approaches to SNR of series-connected elements. The article compares "p" and "gamma" network reduction techniques (NRT). Taking into account specific nature of EPS, the paper proposes the "gamma" NRT for practical calculations of the EPS structural reliability. The paper also considers implementation of the rhomb NRT at the stage of renewal of the rank 2 nodes. This method is based on parallel calculus of the SRI, which permits substantial speed-up of the design procedure.