Logarithmic droop‐based decentralized control of parallel converters for accurate current sharing in islanded DC microgrid applications
Reena Monica P, M. Kowsalya, Josep M. Guerrero
Abstract
Abstract Remarkable progress in distributed power generation invigorated research into DC microgrids using a controllable DC–DC converter contingent to the functionalities therein. The study explores the circulating current issue in a parallel‐connected DC–DC converter and its associated current‐sharing capability. Despite, the conventional droop being a promising solution with less control complexity, the current sharing is achieved at an expense of voltage drop. The prime objective of this research work is to design a control strategy that guarantees a minimized circulating current with proper current sharing for a parallel‐operated DC–DC converter. This paper puts forth a dual reference‐based control to alleviate the droop and load effects of the system. The primary reference is generated by considering the effect of a marginal change in the input power of the converters. The virtual resistance‐based droop technique utilizes the prime reference for secondary droop reference generation. A current sharing algorithm is designed to assimilate adaptability to the scheme running under a variable line and load parameters. The comprehensive approach to the proposed control strategy has the advantages of improved current sharing and voltage regulation. A parallel DC–DC converter with the proposed control mechanism was investigated using MATLAB/Simulink and validated experimentally.