Open AccessAdaptive complex virtual impedance control scheme for accurate reactive power sharing of inverter interfaced autonomous microgrids
Author(s) -
Zandi Farshad,
Fani Bahador,
Sadeghkhani Iman,
Orakzadeh Ardavan
Publication year - 2018
Publication title -
iet generation, transmission and distribution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.92
H-Index - 110
eISSN - 1751-8695
pISSN - 1751-8687
DOI - 10.1049/iet-gtd.2018.5123
Subject(s) - microgrid , voltage droop , ac power , computer science , control theory (sociology) , controller (irrigation) , inverter , electrical impedance , network topology , electronic engineering , voltage source , voltage , topology (electrical circuits) , engineering , control (management) , electrical engineering , agronomy , artificial intelligence , biology , operating system
The mismatched feeder impedance of the voltage‐sourced converter (VSC) units may result in reactive power sharing error in the islanded microgrids. This study presents a reactive power sharing strategy for single‐phase inverter‐based microgrids that eliminates the circulating currents and reduces the coupling between real and reactive powers. The proposed controller is based on an adaptive complex virtual impedance that aims to equalise the E − Q characteristic output of VSCs. The resistive term regulates the virtual voltage drop using the proposed Δ R v − P droop characteristic, while the inductive one controls the phase angle of VSC current and increases the X / R ratio of the microgrid. The proposed strategy does not require a central controller and knowledge of the microgrid lines and loads data and is applicable for the various microgrid topologies. Furthermore, it employs the unidirectional low bandwidth communication link and is robust against the delay and failure of communication channels. The proposed method is implemented using the conventional droop control scheme and presents the medium plug and play capability. Both simulation and experimental case studies using various microgrid topologies are conducted to demonstrate the merits of the proposed scheme.