Market clearing for a wind-thermal power system incorporating wind generation and load forecast uncertainties

Abstract

This paper proposes market clearing mechanism for wind-thermal power system, including uncertainties in wind power generation and load demand. The stochastic behavior of wind speed and wind power is represented by Weibull probability density function (PDF), and the load demand is represented by normal PDF. This paper considers two objectives: total cost minimization and the system risk level minimization. The total cost minimization objective includes costs due to overestimation and underestimation of available wind power, and load demand, along with the cost of energy provided by conventional thermal generators and wind generators. System risk level is considered as an another objective, because wind power prediction is uncertain and highly dependent on the weather conditions. The proposed market clearing model provides a compromise solution by optimizing both the objectives using multi-objective Strength Pareto Evolutionary Algorithm 2+ (SPEA 2+). The effectiveness of the proposed approach is conformed from the results on IEEE 30 bus system.