Authors: E.J. Molina Martínez, F.J. López-Alcolea, A. Parreño Torres, Ismael Payo, J. Vázquez, P. Roncero-Sánchez.
Publication access here.
This article presents the design in the discrete domain of a scheme to control the current injected into the grid with a single-phase inverter. The inverter is connected to the grid through an LCL filter that eliminates the switching harmonics present in the output voltage. To obtain a good dynamic response, the control scheme attenuates the resonant frequency of the LCL filter. The control is based on a scheme with two nested regulators, in which a resonant regulator is included, which allows choosing the location of the closed-loop poles of the system without using observers and measuring only the network current. Design parameters can be obtained with a simple mathematical approach involving only real operations. Both the simulation and experimental results demonstrate the good operation of the control.