LAUSR

This paper presents a photovoltaic (PV) array-integrated dual-boost isolated dc-dc converter-fed three-phase micro-inverter for the grid-connected applications. The coupled inductor and high-frequency DC link-based dc-dc converter offer more advantages over the conventional dc-dc converters used in the grid-tied PV system. A controller with an inner voltage control loop and frequency control loop is proposed to operate the converters of a micro-inverter to transfer the maximum power generated on the PV array to the grid. The inner voltage control loop generates the required control signal for the proposed high step-up dc-dc converter to extract the maximum possible power from the PV array during sunny days. It eliminates the need of cascaded connection of dc-dc converters. High maximum power point tracking (MPPT) accuracy, high voltage gain, and high energy conversion efficiency can be attained with the proposed system. The principles of operation and design considerations of the dual-boost isolated dc-dc converter-fed micro-inverter are presented. The MATLAB/Simulink simulation results are presented to validate the performance of the proposed three-phase micro-inverter.