Consideration of capacity adequacy criterion in optimizing the prospective structure of electric power system

Abstract

This paper considers a method for optimization of the prospective structure of electric power system (EPS), with account made for two criteria: cost-efficiency (minimization of specific reduced energy costs for customers) and capacity adequacy (minimization of capacity shortage probability). The proposed procedure is based on application of a genetic algorithm. The results of procedure evaluation have been considered by the example of optimization of the structure of generating capacities within a concentrated electric power system. When planning EPS, engineering solutions should be examined that may be grouped in technologies based on the type and performance-based indicators. Technologies of generation development cover power station units and power generation plants of various types of different unit capacity. Technologies covering the development of electrical networks are as follows: construction of new power transmission lines of various voltage classes as well as means of reactive power compensation making possible to expand their capacity. Each technology should be provided with performance indicators and reliability data so as to ensure the calculation of target functions. Parameters related to the demand of power supply in EPS must be given as source data: forecast power consumption, peak electrical demands and electricity load curves, nonconforming load indicators with details for every node of electric power system. To solve the problem while considering its discreteness and availability of two criteria, it is suggested to use a genetic algorithm. The calculation of target functions at each algorithm step is carried out by applying the Monte-Carlo technique. Compared to the standard problem statement of EPS planning, the solution of the proposed problem allows not only taking into account regulatory requirements as to EPS capacity adequacy but also selecting an optimal level of capacity adequacy on the basis of evaluation of a rise of costs incurred for providing the same, with due account made for the structure of a specific EPS and potential engineering solutions.