A Step by Step Design Procedure of PR controller and Capacitor Current Feedback Active Damping for a LCL-Type Grid-tied T-Type Inverter

Distributed power generation systems use power electronics converters as interface for connection to grid. The connection through an LCL filter offers certain advantages, but it brings also the disadvantage of having a resonance frequency. Power electronic converter control is challenging due to filter resonance peak. In this paper a three level ultra-efficient converter called T-Type converter is connected to grid through an LCL filter and its injected current is controlled by PR controller. The resonance peak of the filter is also damped using filter capacitor current feedback. A step by step mathematical design procedure for controller and filter capacitor current feedback coefficient is investigated in details. Simulations are carried out in MATLAB/Simulink environment and results depict suitable performance of the system with designed parameters.