With the development of large-scale wind power integration, wind curtailment appears around the world, especially in China. It is essential to perform the assessment on capability of wind power accommodation (ACWPA) by calculating the maximum admissible wind power which plays an important role in system planning and operation. This paper proposes a long-term assessment on the maximum level of wind power installed capacity in future years based on peak power regulation, with consideration of potential wind curtailment. Meanwhile, a short-term assessment based on wind power forecasting is developed through day-ahead unit commitment to get admissible zone of wind power in grid operation. In particular, the extreme wind variation scenario (EWVS) calculated by quadratic programming (QP) is applied to optimize upper limit of admissible zone. Case studies are carried out to analyze wind power characteristics in a province in Southern China. Results show that the proposed approaches can effectively and accurately evaluate the capability of wind power accommodation in regional power grids. (C) 2018 Elsevier Ltd. All rights reserved.