Power flow limitations for LCL grid-connected Power Converters

The controllers of VSI Power Converters connected to the electrical grid can produce line currents in phase (or not) with respect to the phase-to-neutral voltages. The amplitude of the currents and the phase difference are determined by the control signal, and they are limited by the passive elements of the LCL input filter, the grid impedance, the dc bus voltage, the maximum bearable power by the converter and the control signal itself. In this paper, the role of each element is studied in order to determine the final operation region of the power converter. These limitations can be useful to design the LCL filter and the converter´s operation range.