Self-organized criticality analysis of power grids based on electric structure-load entropy

Analysis of the influence of cascading failure in power grid was presented based on electric-structure-load entropy, by observing the initial load entropy and the variation of load entropy in the process of cascading failure to get the effecting of it´s inhibition and spread. Load entropy can effectively quantify the imbalance of electric-structure-load between transmission lines of the distribution of state, considering the circuit equations based on Kirchhoffs law, Power grid structure and the characteristics of transmission lines, can reflect the self-organized criticality of power grid. Numeric example of IEEE 118-bus system shows load entropy can reflect the self-organized criticality of power grid at the beginning and in the process of cascading failure, estimate whether the system reach it´s self-organized criticality, and this can provide a basis for defensive strategy making.