With the advancement in manufacturing and fabrication process, utilization of PV energy systems is increased throughout the globe which leads to the increase of research over lifespan and reliability index on an entire PV system. This increment results in low average manufacturing as well running costs of the entire PV system. The most important portion of the PV system apart from the PV module is the inverter unit which provides conversion and synchronization between the PV system and OLGS. With vast research carried over design as well controlling the architecture of Inverter, it becomes a tedious task to choose the optimal design based on the application area and capital cost. In this paper, we discuss issues faced by the inverter units on the platform of reliability and life span along with the suitable survey. Further to conclude the work result of Inverter unit connected to selected PV module when connected to OLGS.

Every Renewable based energy source requires an additional buffer unit to deliver power to either a standalone system or a grid system. Most of the time unit buffer either provides constant voltage DC-power or AC-power. Higher efficiency in the conversion process can only be achieved if ongoing losses of the buffer system are low. Square sine control approach for Higher-Order Series-Parallel resonant DC-DC Converter is presented in the paper which provides excellent results in both highly and lightly loaded conditions. This control also provides stable bandwidth for input voltage source acceptance which is mostly to be considered as a PV-based source. The strategy also enhances the reliability of the converter by providing a stable and most delightful way of soft switching triggering so as to maintain the output voltage by un-affecting the switching cycle of the Solid-State Semi-conducting Device (SSSD). Selection for the components used in converter design was also studied with a susceptive case study. Further to this control for the entire converter unit is maintained to single variable control so as to reduce the complexity of the system and enhance efficiency. The simulated results of the programmable single variable square sine-wave control is presented for the higher-order resonant converter operating under variable input condition.