Active Cancelation of Equivalent Grid Impedance for Improving Stability and Injected Power Quality of Grid-Connected Inverter Under Variable Grid Condition

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalNot applicablepeer-review

8 Scopus Citations
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Author(s)

Detail(s)

Original languageEnglish
Pages (from-to)9387-9398
Journal / PublicationIEEE Transactions on Power Electronics
Volume33
Issue number11
Online published15 Jan 2018
Publication statusPublished - Nov 2018

Abstract

An active grid impedance cancelator using the concept of series active filter to suppress the effect of the grid disturbance and stabilize the single-phase grid-connected inverters with an inductive–capacitive–inductive filter operating under variable grid conditions is presented. Harmonic interaction between the inverter and the grid is thereby avoided owing to the cancellation of equivalent grid impedance. More importantly, the impedance cancelator offers an active damping function to ease the heavy burden of the inverter control, such as power control, phase locked loop, current regulation, impedance shaping, etc. The impedance cancelator is a full-bridge dc-ac converter having no passive inductive-capacitive filter. It is connected in series with the inverter output and is operated as a negative virtual grid impedance. As the volt-ampere rating of the impedance cancelator is low, the efficiency of the entire system is not sacrificed. Starting with the impedance-based analytical modeling method, the basic principle of equivalent grid impedance cancelator is derived and studied. Then, the digital control strategy and the modeling of equivalent grid impedance cancelator are examined. The experimental results of a prototype cancelator for a single-phase inverter is favorably compared with theoretical predictions.

Research Area(s)

  • grid impedance cancelator, Impedance, impedance-based stability criterion, Inverters, inductive–capacitive–inductive (LCL) filter, negative virtual grid impedance, Power filters, Power harmonic filters, Power system stability, Single-phase inverters, Stability criteria, weak grid

Citation Format(s)

Active Cancelation of Equivalent Grid Impedance for Improving Stability and Injected Power Quality of Grid-Connected Inverter Under Variable Grid Condition. / He, Yuanbin; Chung, Henry Shu-Hung; Lai, Chun-Tak; Zhang, Xin; Wu, Weimin.

In: IEEE Transactions on Power Electronics, Vol. 33, No. 11, 11.2018, p. 9387-9398.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalNot applicablepeer-review