Grid interconnection of distributed generation system with power quality improvement features

This paper presents the modelling and control of grid interfaced Distributed Generation (DG) system with embedded active filter function. The output of the DG is given to the DC side of the Voltage Source Inverter for interfacing to the Grid. In the presented work, the features of Active Power Filter have been incorporated in the control circuit of the current controlled-voltage source inverter interfacing the DG to the grid. Thus the same inverter is utilised to inject power generated from DG source to the Grid and also to act as Shunt Active Power Filter to compensate for load current harmonics and reactive power demand. Thus, after compensation, the Grid current is sinusoidal and in-phase with Grid voltage. The entire system is modelled in MATLAB/Simulink environment and simulations carried out to verify the operation and the control principle. Various simulation results are presented for the proposed Grid interfaced DG system.