Analysis on the Self-Organized Critical State with Power Flow Entropy in Power Grids

The existence of the self-organized criticality has significant consequences for power system operation. Different from the previous cascading failures models in power system, a novel conception, entropy of power flow which can represent the distribution of power flow, is introduced to study the effect of heterogeneity to critical state. Simulation results show that the load loss for cascading failure increases as the power flow entropy adds and increase sharply when the entropy be large enough even with the system at very low loading level. It is affirmed that the power tails and the consequent risk of large blackouts could be substantially reduced by lowering power flow entropy to obtain an exponential tail for large blackouts.