A novel security stochastic unit commitment for wind-thermal system operation

Wind power has brought significant uncertainty to power system operation. How to achieve the most economic unit commitment in the premise of ensuring system security is an important issue needed to be addressed. This paper proposes a novel security stochastic unit commitment method to accommodate the volatile wind power injection. Focusing on the interval of wind power distribution, the worst-case impact of wind power volatility on unit commitment can be considered by interval linear programming, so that the proposed model can always provide a secure and robust commitment result to the operators. Within this security boundary determined by interval number analysis, a chance-programming based method is used to achieve the stochastic optimal solution considering the probabilistic distribution of wind power. Thus, the optimal and secure commitment results can be acquired. Benders decomposition is also implemented to reduce the scale of mixed integer programming. The numerical results indicate better secure and economical features of our proposed security stochastic unit commitment method comparing with the traditional one.