Key Technologies of Grid-Forming Energy Storage in New Power Systems

This document discusses the key technologies of grid-forming energy storage under the new power system, which is characterized by a high proportion of renewable energy and power electronic equipment. It first analyzes the demand for grid-forming energy storage, highlighting challenges such as broadband oscillation, transient overvoltage, and frequency stability caused by the integration of intermittent renewable energy. The principle of grid-forming control is then explained, contrasting it with grid-following control, and emphasizing its ability to provide inertia and voltage support like synchronous generators. The document details the role of grid-forming energy storage in providing short-circuit current, dynamic reactive power support, inertia support, impedance reshaping, oscillation damping, and additional control for complex scenarios. Key technologies covered include grid-forming control strategies (droop, virtual synchronous generator, matching control, virtual oscillator) and critical issues such as synchronization stability of multiple voltage sources, current limiting protection, and coordinated control of converters. The document concludes with the current status and prospects of grid-forming energy storage, positioning it as a crucial solution for enhancing power system stability in the evolving energy landscape.