Analysis of optimization Strategies for Grid-Side Converter Control during Grid Faults using DSRF Control

Wind energy conversion systems and photovoltaic systems are leading renewable energy sources for the supply of electric energy. As most renewable energy sources are connected to the grid through converter systems, demanding grid code requirements need to be met and advanced control strategies have to be developed and implemented. This paper analyses the DSRF control with different optimization methods with special regard to over-currents and unbalanced currents, oscillations of active and reactive power as well as oscillations of the intermediate circuit voltage. The decoupled double synchronous reference frame - PLL is used for a fast and robust positive and negative voltage sequence synchronization.