Research on Voltage Source and Current Source Control of Three-phase Grid-connected Converter

The grid-connected converter is the main interface between distributed generation and grid. The research can ensure its stable operation under different grid conditions, and it is crucial to promote the development of renewable energy. The control of grid-connected converter can be divided into voltage source control (VSC) and current source control (CSC). In this paper, the influence of grid impedance on converter’s stability is analyzed in both VSC and CSC controls, and a switching control strategy is also proposed to meet the need of switching between different controls. On the basis of theory analysis, the simulations based on Simulink have been conducted, and the results show that the proposed switching control strategy can achieve smooth switching between different controls without obvious surge current.