FPGA based control scheme for a single-stage grid-connected solar photovoltaic system

Abstract

This work focuses on the design and development of FPGA-based digital controller for the grid connected solar Photo-Voltaic (PV) systems as a distributed generation. The proposed grid connected PV system is able to deliver a sinusoidal current to the utility grid in-phase with grid voltage. In this work, the system is operated in discontinuous conduction mode. The advantage of this mode of conduction is that it feeds sinusoidal current with near to unity power factor into the grid. Due to the versatility of Field Programmable Gate Array (FPGA), it offers significant advantages in high performance and low volume applications. The level of optimization in FPGAs is very high in comparison to microprocessors or Digital Signal Processors (DSPs) as FPGAs allow customizable bit-widths and massive instruction-level parallelism. The proposed FPGA-based control scheme for single-stage grid connected photovoltaic system generates switching pulses in such a way that sinusoidal current with unity power factor is injected into the grid.