Modeling and stability issues of voltage-source converter dominated power systems: A review

Abstract

With the intensively increasing proportion of voltage source converter (VSC) based equipment, traditional power systems with synchronous generators (SGs) as the major constituent gradually evolve into VSC dominated ones. In the meanwhile, the need for modeling and stability assessment of such systems urgently arises, since the pertinent low inertia and weak damping features impair the systems' ability to resist random disturbances. To this end, existing works model the system dynamic processes starting from various (i.e. time, frequency and energy) domains, and analyze/determine the system stability under small or large disturbances. Among them, the small-signal stability assessment mainly adopts the time-domain analysis based on the state-space model and the frequency-domain methods based on the impedance model, phase-amplitude dynamics model and static synchronous generator model. The large-signal stability assessment mainly exploits the time-domain simulation with detailed model (i.e. continuous/discrete-time mixed model with differential-difference-algebraic equations), and the energy-domain analysis based on energy function models. This paper presents a comprehensive review of existing modeling and stability analysis methods for VSC dominated power systems, including their basic principles, key features, application scenarios and development tendencies. Key technical issues related to modeling and stability analysis are also summarized.