Transient response evaluation of stationary‐frame resonant current controllers for grid‐connected applications

This study deepens on the transient response analysis of the so‐called vector proportional–integral (VPI) controllers and compares them with the popular proportional–resonant (PR) controllers for grid‐connected applications. The employed methodology is based on the study of the error signal roots: both reference tracking and disturbance rejection abilities are considered for proper gain tuning. This study proves that PR controllers lead to shorter settling times than VPI controllers. A three‐phase voltage source converter prototype has been implemented. Experimental results comparing the transient behaviour of VPI and PR controllers in different conditions are provided: a + 90° phase‐angle jump in the current reference and a ‘type C’ voltage sag at the point of common coupling.