Evaluation method of renewable energy flexibility confidence capacity under different penetration rates.

As the penetration rate of renewable energy continues to increase, reliability confidence capacity, an important indicator for measuring the contribution of power sources to the power system, has received widespread attention in the planning and design of power systems. However, reliability confidence capacity can no longer be fully applicable to the planning and design of new power systems with renewable energy as the core feature. Therefore, this paper proposes the concept of renewable energy flexibility confidence capacity and constructs a mathematical model. Firstly, based on the consideration of flexibility, a renewable energy flexible confidence capacity evaluation model is established using the sequential Monte Carlo method. Secondly, the changes and reasons for various flexibility indicators in the system under different energy penetration rates are analyzed. Then, the differences and reasons for renewable energy flexibility confidence capacity evaluation results under different energy penetration rates are compared and analyzed. Based on the weights of various flexibility indicators, the renewable energy flexibility confidence capacity under different energy penetration rates is comprehensively evaluated. Finally, the actual power grid data of a certain region in Xinjiang, China is simulated and analyzed. The results of the case study verify the rationality and effectiveness of the proposed method. • System balancing mechanism under different energy penetration rates is analyzed. • A renewable energy flexibility confidence capacity index is proposed. • Evaluation method for renewable energy flexibility confidence capacity is proposed. [ABSTRACT FROM AUTHOR]