PI+resonant controller with active damping for high efficiency PV-module-integrated buck inverter

Module Integrated Converters (MIC) are a good choice for connection PV modules in the electrical grid. The main goal of this work is to propose and present a new grid current controller for a buck inverter using a single PWM switch and an unfolding H-bridge, which quite reduce the switching losses. To achieve this purpose, two loop control system is needed. It consists of an internal grid current loop and an external DC-bus voltage loop. For connection the system in the grid is used a LCL filter. The problem of resonance filter is solved with the virtual impedance (active damping), demanding no additional sensor. Results from hardware in the loop are obtained to validate the theoretical analysis.