Transformer coupled multi-input two stage standalone solar photovoltaic scheme for rural areas

In this paper a transformer coupled multi-input dc-dc converter (TCMDDC) based solar photovoltaic system for standalone applications is proposed. The proposed TCMDDC can realize maximum power point tracking and battery charge control while maintaining proper voltage level. In the process it allows reduction in number of power conversion stages as compared to the existing standalone schemes. This leads to enhancements in efficiency and reliability of the proposed scheme. Further, it allows the use of low voltage levels for solar PV array and battery thereby eliminating concerns pertaining to the safety of personnel and equipment. A suitable control strategy that allows the TCMDDC to operate in different modes that are encountered in a standalone scheme is also devised. The viability of the scheme is ascertained through detailed analytical and simulation studies.