Current control of voltage source converters connected to the grid through an LCL-filter

The aim of this paper is to propose a current control of VSCs connected to the grid through an LCL-filter. The proposed algorithm controls the grid current using only two sensors. Other variables are obtained with a state estimator, and the possible disturbances of the system are attenuated with active damping. The control algorithm has been proved for different disturbances, such as temporal variations in the components of the model and perturbations in the grid, and also with the linear and nonlinear models.