A Single-Stage Multiport Bridgeless Boost Architecture for Grid-Connected Renewable Energy Integrated with BESS
In grid-connected hybrid renewable energy systems, high-frequency power converters became widely used to enhance the power density and energy efficiency. This paper presents a new modularized high-frequency DC-link integration methodology that connects multi-input renewable energy sources involves battery energy storage system (BESS) to the AC-grid. A grid-tie-inverter with variable line inductor is introduced to control the active-reactive power flow as well as the harmonic distortion of the injected current. To minimize the converter physical size with improved system efficiency, a high frequency-based multisource bridgeless boost (MBB) architecture is proposed here. A direct-mount decoupling snubber capacitor and zero-voltage switching are used to reduce the switching losses resulted from the high-frequency operation. To investigate the system performance, a comparative study between the proposed system and other conventional multisource converter architectures; as bridge-based (BB) and bridgeless power factor (BPF), is introduced. A direct digital approach is used to design the system controller in Matlab/Simulink R2016a environment. To validate the system performance, a 10 kW multi-source grid-connected experimental setup with dSPACE-1104 controller is constructed and tested. The test results verify the effectiveness of the proposed architecture for grid-connected hybrid renewable energy conversion systems.
Keywords - Hybrid Renewable Systems, Multi-source Boost Converter, Digital Control, Voltage Source Inverter.