Design of a Solar Pumping System with Battery Storage Based on Three-Port DC-DC Converter

This paper introduces a design for a photovoltaic (PV) pumping system that incorporates battery bank storage. A three-port DC-DC converter (TPC) is employed to integrate the PV, battery bank, and induction motor drive (IMD) based pumping system. The purpose of the battery bank is to provide support to the pump during shading conditions to prevent frequent suspension and down-thrust situations. Additionally, the proposed system aims to maintain the free-floating impeller operating range by imposing rotational speed limits on the pump. The input ports of the TPC consist of the PV port, which is controlled to harvest the maximum power point (MPP) using the perturb and observe technique, and the battery port. The output port is linked to a DC bus using passive rectifier to supply power to the variable speed V/F IMD. The battery port is regulated to sustain the DC bus voltage in a desired voltage range that ensures the impeller operation under free-floating conditions. The proposed system is simulated using MATLAB/Simulink software. The simulation results are discussed to evaluate the dynamic performance.