Power system restoration plan using the characteristics of scale‐free networks

Abstract

SUMMARYA reliable electricity supply infrastructure is fundamental to modern living. An interruption to electricity services has such far reaching impact to our everyday lives to various industries compared to other service interruptions, thus to build in significant redundancy and various preventive measures to electric power system operation and planning is needed. Just as important as to incorporate redundancy and preventive measures however, an effective restoration plan needs to be in place since the possibility of electricity service interruption cannot be eliminated completely.In this paper, a novel power system restoration plan that utilizes the characteristic of so-called scale-free networks is proposed. For a scale-free network, the importance of each node is determined based on the number of connections made to other nodes in that the nodes with many connections, thus important, are called ''hubs.'' A scale-free network is a special complex network which follows a power law distribution, that is few hubs and many nodes with few connections at various system sizes. In the proposed plan the hubs are restored before other insignificant nodes in the system. It is shown that by doing so, the total restoration time can be reduced considerably, and notable improvements can be achieved with respect to the objective function in the mathematical formulation of electric power system restoration problem with a few constraints introduced in this paper. The effectiveness of proposed plan is tested with one of the planning problems such as valuation of black-start capable generators using IEEE-30 bus system.

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A new optimal contingency-based design for placement of gas turbines to enhance black-start capability

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“…The objective of this stage is mainly to maximize the generation capability. In this regard, many researchers have formulated this objective as an optimization problem . In El‐Zonkoly and Sun et al, authors propose an algorithm that formulates generator start‐up sequence as a mixed integer linear problem.…”