Power angle control of a single phase grid connected photovoltaic inverter for controlled power transfer

Abstract

This paper focuses on the design and development of a 500 W, single phase single stage low-cost inverter for the transfer of direct current (DC) power from the solar photovoltaic (SPV) panel to the grid while meeting the standards for interconnection. The power transfer from SPV to grid is facilitated by controlling the angle between the inverter voltage and the grid voltage i.e. the power angle or phase angle (δ). Simulation of the single stage inverter for a power rating of 500 W is implemented in MATLAB/Simulink. The synchronization of the inverter with the grid was carried out by monitoring the grid frequency continuously and updating it. The power transferred to the grid is made equal to the available power by moni- toring and updating δ. A pulse-width modulation (PWM) control is implemented using PIC16F877 microcontroller for the inverter so as to deliver the available power from the solar panel to the grid, as well as, make the frequency of the output voltage of the inverter equal to the grid frequency for sustaining the synchronization.