With the increased penetration of distributed generation

the power grid will gradually develop into a converter-dominant network with low inertia and under-damped

which leads to stability problems becoming more and more serious. Virtual synchronous generator (VSG) control technologies can mimic the mechanism of synchronous generator to improve the system stability

which earns it more concern and wide application. Firstly

the architecture and principles of the virtual synchronous generator control system are described

and then some key issues about VSG modeling

operation control

stability analysis and typical application are deeply reviewed. Many potential research hot points and solutions about VSG are also proposed. This work is supported by National Natural Science Foundation of China (No. 51321005

No. 51567021)

National High Technology Research and Development Program of China (863 Program) (No.2012AA050204) and Qinghai Province Key Laboratory of Photovoltaic Power Generation and Grid-connected Technology (No. 2014-Z-Y34A).