The paper presents a novel "cross-forming" control concept for grid-forming inverters operating against grid faults. Cross-forming refers to voltage angle forming and current magnitude forming, differing from classical grid-forming and grid-following concepts.
The key highlights are:
The cross-forming control is motivated by device security requirements for fault current limitation and grid code requirements for voltage angle forming preservation. It aims to address the technical challenges in limiting fault current, maintaining transient synchronization stability, and providing fault ride-through (FRT) ancillary services simultaneously.
Two feasible control strategies are developed to realize the cross-forming concept - angle-enforcing and current-enforcing cross-forming control. These strategies result in an equivalent system featuring a constant virtual impedance, differing from prior results.
An equivalent representation of the cross-forming inverter system is derived, which conforms to the normal form of current-unsaturated grid-forming systems. This allows extending existing transient stability analysis approaches and results to current-saturated conditions.
Simulation and experimental validations demonstrate the efficacy of the proposed cross-forming control in fast current limiting, preserving grid-forming synchronization, and providing FRT ancillary services.
The cross-forming control is fast-acting, able to fully utilize the overcurrent capability, adaptable to various disturbances, simple to implement, easy to tune, and robust in stability performance, serving as a promising candidate for future grid-forming product development.
Ke Bahasa Lain
dari konten sumber
arxiv.org
Pertanyaan yang Lebih Dalam