Static Security Assessment of Large Power Systems under N-1-1 Contingency

Abstract

—Contingency analysis (CA) is one of the critical tools of a static security assessment (SSA). It is used to forecast the operating states of a power system under one or more outages of generators, transmission lines, transformers, etc. To perform SSA, repetitive load flow analyses are required for obtaining the bus voltages, bus injections, and line flows considering each possible outage. A repetitive load flow analysis demands huge computational efforts like efficient system modelling for faster load flow solutions, parallel programming and High performance computing (HPC). In this paper, an N-1-1 CA has been anal ysed using fast decoupled load flow (FDLF) with a strategy of screening and ranking the catastrophic contingencies. This paper explores a computationally efficient method to analyze the severity and the ranking of N-1-1 contingencies for large power system SSA. The performance of the FDLF based SSA method is demonstrated on two standard IEEE 14 and 118 bus systems.