Substation PSA model

Abstract

Chapter 6 describes how to create the substation model, the core of the PSA application, for grid security. The model consists of event trees and fault trees described in Chap. 4. First, the modelling principles and then the details of the model are presented. The properties of the model are based, to some extent, on the actual Finnish 400 kV transmission grid, which shows that the method is applicable to grids of real size. The example presented to illustrate the method is for line faults. The steps presented in the Chapter and needed in the construction of the substation reliability model are: • The selection of credible events (faults) for analysis and their frequency. Fault frequencies might vary according to the season. • Defining the substation functionality: the busbar and circuit breaker arrangements that affect the construction of the substation reliability model. • The selection of grid topologies and power flows included in the analysis. • Defining the extent of the model, for example the main protection relays, the structure of the protection, fault clearance times, the local and remote backup protection and their functionality, breaker failure protection. • Defining the principles for event tree and fault tree construction. • The construction and analysis of event tree and fault trees. © Springer-Verlag London Limited 2011.