A Method for Calculating Aggregate Flexibility Parameters of Virtual Power Plant Based on Improved Column and Constraint Generation Algorithm

Abstract The virtual power plant (VPP) can aggregate massive, dispersed, and heterogeneous distributed energy resources (DERs) provide an effective management way for active distribution system (ADS). In this paper, three parameters of upper lower limits output, ramping, discharging is used to describe the flexibility VPP. Based on this, a two-stage robust optimization (RO) model with dispatch instructions (DI) from superior grid (SPG) as uncertainty variables was constructed. Considering that range DI SPG changes during iteration column constraint generation (C&CG) algorithm, position set proposed record boundary information uncertain issued by when sub-problem (SP) finds worst scenario in each iteration, corresponding constraints are added master problem (MP). For solution SP, bilevel max-min firstly transformed into single-level bilinear programming (BLP) duality theory then solved concave-convex process (CCP) iterative method. Compared transforming BLP mixed integer (MILP) based Karush-Kuhn-Tucker (KKT) condition, it not only meet engineering accuracy but also greatly save time. Finally, effectiveness algorithm verified modified IEEE 33-bus system.