Research on Quantitative Model of Power System Flexibility Demand Based on Polyhedron

With the increasing flexibility demand in new power system and it multi-time-scale fluctuation characteristics, traditional methods that separately quantify regulation capacities-such as frequency regulation and ramping-often lead to excessive reserve redundancy. Therefore, accurately quantifying power system flexibility demand is crucial to enhancing operational safety. This paper proposes a polyhedral model to quantify power system flexibility demand. First, the joint fluctuation domain of the multi-dimensional random power time series of both source and load sides is described. Second, the joint fluctuation domain of multidimensional random sources within the power system is characterized as multiple cells, and the spatial distribution of flexibility requirements in the park is projected and calculated for these joint cells. Finally, a case study on a typical power system validates the model's effectiveness.