Development of grid-connected inverters for micro-grid

As an important part of the smart grid, the micro-grid contains distributed energy sources, loads, and control devices. An energy storage system and a doubly fed induction generator based wind turbine associated with an ultracapacitor are the main micro grid sources in this paper. Both the energy storage system and the dual-fed induction generator systems are connected to the micro-grid via grid-connected inverters and an LCL filter. Decoupled q-d control strategies for different operating conditions of the systems are demonstrated in this paper. Matlab/Simulink is employed to investigate the performance of these energy sources and inverters.