Design and Hardware Implementation of a Versatile Photovoltaic Power Generating System

Abstract

This paper presents a novel standalone photovoltaic (PV) power generating system. PV based power generating units performing the direct conversion of solar energy into electric energy constitute a major area of renewable energy based power generating systems. In practice, PV based power systems can be used to exploit the solar energy in almost all kinds of industrial and residential applications; however, designing a PV system depends on a variety of factors, such as, geographical location, solar irradiation, system configurations, operating modes and most importantly the load requirements. In this paper, a versatile standalone PV power system equipped with a battery energy storage unit is designed for a variety of small to medium power applications. To achieve a cost-effective design, both buck and buck-boost dc to dc converters are integrated to facilitate the maximum power point tracking (MPPT), battery charging/discharging and load voltage regulation functions. The details concerning the design concept of the proposed system and the related circuit operating theory are firstly addressed and followed by a set of practical tests on a dspic4001 controlled hardware prototype. Typical measured results are presented to demonstrate the feasibility and effectiveness of the proposed system