A Solution to Unit Commitment Problem at the Presence of Renewable Energy Resources

Nowadays the role and impact of renewable energy resources (RER) penetration in power system operation and scheduling is increased dramatically. Because of intermittent and probabilistic behavior of RER power and uncertainty in RER output power, unit commitment (UC) at the presence of RER is a more complicated optimization problem. This paper proposes an innovative and effective modeling procedure based on modification of the Harmony Search Algorithm (HSA) to solve the UC in power systems with and without RER. The proposed algorithm is easy in application compared to the other heuristic methods and has a high capability in reaching to optimal solution with reasonable time. The proposed method is tested on 10 units test system for base case and modification to new test case including wind and solar power plant. To preserve the general structure of economic dispatch equation, the wind and solar power plant operating cost is modeled with a quadratic equation similar to thermal units. Simulations were done for daily units scheduling. Numerical results show the lower operating cost for 10 units system at the presence of RER. The efficiency and improvement of the solution in cost and execution time compared to the results of the other powerful heuristic algorithms is compared.