Technological Developments in Direct Grid Connected Power Converters for Solar PV Power Plants

Most of the countries in the world are concentrating on renewable energy generation, due to day-day increase in population increasing the energy demand, also to make their environment sustainable. With the many of features, use of megawatts rating solar photovoltaic (PV) power plants are becoming more popular for upgrading the existing power generation throughout the world. Moreover, among the existing renewable energy generations, solar power is the primary choice to meet the rapidly increasing demands; since solar PV plant installing time is relatively quick, say about in 3- 4 months, compared to conventional (thermal, hydro & diesel) plants which may require about 3-4 years. The low voltage (270‒700V) power converters require a filter and a step-up transformer for interconnecting the local grids with solar PV power plants. The advances in power converters without transformers and filters have recently become more attractive for solar PV power plants connected directly to grid. The study of this article describes the essential requirement and the technological developments in the design of power electronics converters, together with their modulation schemes to integrate solar power directly with standard power grid. This article, review ongoing research activities and the probable directions for the future research in developing inverters for cost-efficient grid connected solar PV plants.