Exploiting the DC‐Energy Storage Collaborative Frequency Support Capability for Inter‐Regional Scheduling of RES Bases and Receiving‐End Grids

ABSTRACT

Developing large‐scale renewable energy source (RES) bases in desert, Gobi and barren regions is important for low‐carbon power systems. However, their integration into receiving‐end grids through DC tie‐lines displaces conventional units and brings challenges to power balance and frequency security. To address this issue, this paper proposes a frequency‐security‐constrained co‐scheduling framework for an RES base and a receiving‐end grid under RES uncertainty. First, a stepwise flexible operation model of the DC tie‐line is established to improve the matching between RES base output and DC transmission. Second, an inter‐regional frequency support mechanism is developed by coordinating DC tie‐line virtual inertia and energy storage fast frequency response. Based on this mechanism, a dynamic frequency response model of the receiving‐end grid is derived and reformulated into tractable second‐order cone constraints. On this basis, generative adversarial network (GAN)‐based scenario generation and a probability‐box ambiguity set are combined to model RES output uncertainty and embedded in a distributionally robust co‐scheduling model, minimizing the worst‐case expected cost under frequency‐security constraints. Case studies on a modified IEEE RTS‐79 system and the Ningxia–Hunan inter‐regional power system show that the proposed method reduces online conventional unit capacity by 26.33% and improves RES utilization by 4.52% while ensuring frequency security.