Dynamic optimisation of virtual synchronous generator to enhance stability of power system

Abstract

Virtual synchronous generators (VSGs) are essential for the high penetration of renewable energy sources. VSGs have virtual rotating inertia, a damping effect, and synchronising power such as actual SGs. Such features of VSGs offer a promising structure to improve the stability of power systems. VSGs are required to suppress power and system frequency oscillations. In addition, VSGs must operate within a current limit since they are vulnerable to the overcurrent, unlike actual SGs. The authors propose a novel dynamic and optimal VSG to enhance the frequency stability in power systems while guaranteeing the current limit. The proposed approach determines an optimal tuple of inertia and damping of VSG online and guarantees the current limit with the use of a circuit model. The effectiveness of the proposed method is demonstrated via experiments, comparing it with the conventional methods.