Paper Title
A Buck-Boost Based Dc/Ac Converter For Residential Pv Applications By Using MPPT

Abstract
The studies on the photovoltaic (PV) generation are extensively increasing, since it is considered as an essential in-exhaustible and broadly available energy resource. However, the output power produced from the PV modules depends on solar radiation and temperature of the solar cells. Therefore, to maximize the efficiency of the renewable energy systems, it is necessary to track the maximum power point of the PV array. In the proposed scheme maximum power point tracking is achieved by using perturbation and observation (P&O) method. The single stage architecture is often preferred to realize grid connected Photo-Voltaic generators for residential applications. In fact, by halving the power processing steps, the power losses can be considerably reduced if compared with those of a two stage configuration. However, single stage power conditioners are generally unable to boost the voltage of the PV modules. Therefore, they feature a narrower input voltage range. A new approach to design a power conditioner for standalone PV plants for residential applications is presented in this paper. It is based on the series connection between a buck-boost converter and the PV array. According to such an approach, the buck boost converter processes only a fraction of the inverter input power, while always operating in conditions of high efficiency. Mostly buck-boost converter operates in buck mode. The duty ratio is less than 0.5, so that switching losses are less. An inverter working by SPWM pulses, which gives a pure sine wave is used in this proposed scheme.