Global sensitivity analysis of static voltage stability based on extended affine model

•An extended AA-based interval Taylor expansion was proposed to reduce the conservatism of the evaluation results•A novel framework based GSA method was proposed to clarify the components of total variance contributions•An analytical variance-based GSA method was presented to improve evaluation efficiency of static voltage stability under uncertainties Large scale centralized grid-connection of renewable energy significantly increases the uncertainty of a power system, and accurate analysis and quantitative evaluation of the impact of this uncertainty on the static voltage stability of a power system is the important premise and basis for improving the power system operation security. This paper studies a global sensitivity analysis method of the static voltage stability based on extended affine model. A static voltage stability interval evaluation model based on L index is constructed according to the extended affine arithmetic, and the global sensitivity analysis method based on variance decomposition is introduced to evaluate the importance of the input interval variables on the static voltage stability. The analysis of the simulation results on the IEEE systems shows that the proposed method can suppress the effect of interval expansion more effectively than the traditional affine algorithm, and the global sensitivity analysis method based on analytic variance decomposition can identify the importance of input interval variables more effectively.