Power Conditioning Circuit Topologies

For low-voltage dc energy sources, a power conditioning system (PCS) is needed to convert the energy sources to a higher-voltage dc before making it to ac for grid-tie applications. Solar photovoltaic (PV) and fuel cells are perhaps the most well-known and prospective energy sources with low-voltage dc output. A thermoelectric generator, a battery, and an ultracapacitor are also examples of such low-voltage dc energy sources. Recently, numerous circuit topologies for the power conversion from low-voltage dc to high-voltage ac for grid-tie applications were proposed to deal with specific issues such as high efficiency, low cost, and safety. The aim of this article is to introduce and discuss the main features of these relatively new circuit topologies that deal with these practical design issues. © 2009 IEEE.