Review of Frequency Support Control Strategies for Asynchronous AC Systems Connected Through VSC-HVDC

Abstract

The ability of fast power response of VSC-HVDC can provide frequency support control for asynchronous AC systems connected through VSC-HVDC, which improves the stability of power system by sharing of the spinning reserves among non-synchronous AC areas. Methods that have been proposed to enable VSC-HVDC systems to provide frequency support, including methods base on remote communication, methods based on DC voltage droop, methods based on droop control and methods with virtual synchronous generator characteristic, are reviewed. The performance and application trends of frequency support control of VSC-HVDC are analyzed.