Modified repetitive control based on comb filters for harmonics control in grid-connected applications

Power quality plays an important role in the operation of grid-connected inverters. The injected current should have a minimum harmonic content order to comply with local grid codes. This can be challenging due fact that voltage also distorted. paper presents modified repetitive control method for three-phase inverters by means digital comb filter application. proposed provides multiple harmonics compensation, simple implementation and design. It consists complementing Proportional-Resonant (PR) appropriately tuned filter, which results mitigation output reduced THD. Two types filters been as compensator, namely feedback feedforward structures. compensator included additional FIR low-pass increased robustness. Regardless structure chosen solution is targeted at simplicity analysis, design implementation. Furthermore, based on casual, hence its microprocessors greatly facilitated. two-stage loop ensures stability even case poles being introduced filter. Investigation frequency variations impact included. research was conducted following IT solutions: data workflow management environment, code generation (Matlab), user interface (ControlDesk). experimental demonstrated effectiveness converter operating network distorted supply voltage.