A Three-Input DC-DC Boost Converter for Grid-Connected Hybrid PV-Wind-Battery Energy Systems

Abstract

The growing penetration of renewable energy sources into modern power networks has intensified the need for compact, efficient, and reliable multi-source power-conversion architectures. This paper presents the design, modeling, and MATLAB/Simulink-based validation of a three-input DC-DC boost converter that simultaneously integrates a photovoltaic (PV) array (105 V, 1.5 kW), a permanent-magnet synchronous generator (PMSG)-based wind energy conversion system (80 V, 1.2 kW), and a 48 V/100 Ah lithium-ion battery storage unit onto a single regulated 400 V DC link. Using only four controlled switches and two coupled inductors, the proposed topology replaces three conventional single-input converters, reducing component count by approximately 55% while achieving a peak conversion efficiency of 94.2%. Independent duty-ratio control enables Maximum Power Point Tracking (MPPT) of the PV source, power regulation of the wind source, and bidirectional battery charge/discharge management across three clearly defined operating modes. The regulated DC bus feeds a grid-connected voltage source inverter (VSI) synchronized through a Phase-Locked Loop (PLL) and interfaced to the utility through an LCL output filter. Simulation results confirm stable output-voltage regulation (400 V ± 3 V), a total harmonic distortion (THD) of 2.8%, which satisfies the IEEE 519 limit, and a near-unity power factor of 0.997, validating the proposed converter as an efficient and economical solution for grid-connected hybrid renewable energy applications.