Security Enhancement with Nodal Criticality Based Integration of Strategic Micro Grids

Security enhancement of distribution networks are constrained with multiple causes including limited availability of network resources and high penetration of intermittent distributed generation. In that context, this paper proposes a new methodology to enhance the security of power supply in a distribution network by strategically integrating plug-in hybrid electric vehicle (PHEV) micro grids based on the nodal criticality. The nodal criticality is assessed by integrating operational uncertainties of events into samples of Monte Carlo simulation and then classifying load interruptions on the basis of their magnitudes and frequencies. The load shedding due to criticality of system stress is classified into arrays of clusters on the basis of magnitudes of interrupted loads. The critical clusters that provide the largest disturbances to nodal loads are used as the reference capacities of PHEV micro grids to mitigate impacts. Case studies are performed by applying the methodology into a realistic model of a distribution network. Results depict that the proposed methodology can improve the system-wide security of supply. There are some nodes of which the security of supply can be improved significantly. The levels of improvement in security of supply of nodes are not consistent and some nodes can also receive marginal improvements.