The increasing development of renewable energy systems challenges more and more the parameters of their connection to grid. The connection through an LCL filter offers certain advantages, but it brings also the disadvantage of having a resonance frequency. This project deals with the investigation and the implementation of different methods of active damping of the LCL filter resonance in grid connected applications. In this project, different active damping methods are be reviewed. The control of the inverter is be implemented, including the synchronization with the grid, the current and dc voltage control loop. Also, different active damping methods are implemented and tested under different conditions.