Non-Isolated Partial Power Processing Converter for Battery Energy Storage Systems

This paper presents a Partial Power Processing (PPP) type bidirectional converter for interfacing Battery Energy Storage Systems (BESS) with a DC grid. A non-isolated Series-Pass Partial Power Processing converter is conceptualized, and a Four-Switch Buck-Boost (FSBB) converter is used to realize the power stage. The steady-state analysis of the proposed topology is discussed. A circuit simulation model for the proposed converter is developed, and its operation is validated for different operating modes. A laboratory prototype of the FSBB converter has been developed, and experimental results are presented to validate the functionality of the proposed topology. It is demonstrated that the FSBB converter, rated at 40 % of the total power, facilitates power transfer up to 800 W between the source and the load with a system efficiency close to 94 %.