Identification of most vulnerable line for divergent trend of power flow using Lyapunov Exponent

Abstract

Complexity of power system is increasing due to expansion of interconnections. Blackouts and cascaded failures are associated with divergent situations in power system. Dynamics of power system pushes the behavior differently under different values of parameters such as increase in load demand at very sensitive bus in power system which may trigger exponential rise in power flows through lines leading to cascaded outages one after other. To study impact of power demand at sensitive bus causing divergent flow over lines, paper proposes chaotic performance index as a watchdog for relative divergent trend of power flow assessment. This will help power system planners to formulate artificial intelligent ways to identify weak chaotic bus and most vulnerable line showing divergent growth of power flow in a given power system network. This paper proposes discrete Largest Lyapunov Exponent based computation for dynamic security assessment. For a particular outage one can identify the most vulnerable transmission line based on algorithm presented in paper. Results and discussions will further support viewpoint of such studies.