Suppression of line voltage related distortion in current controlled grid connected inverters

The influence of selected control strategies on the level of low-order current harmonic distortion generated by an inverter connected to a distorted grid is investigated through a combination of theoretical and experimental studies. A detailed theoretical analysis, based on the concept of harmonic i...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on power electronics 2005-11, Vol.20 (6), p.1393-1401
Main Authors: Abeyasekera, T., Johnson, C.M., Atkinson, D.J., Armstrong, M.
Format: Article
Language:English
Subjects:
Applied sciences
Control systems
Control theory
Disturbances
Electrical engineering
Electrical engineering. Electrical power engineering
Electrical equipment
Exact sciences and technology
Feed-forward voltage disturbance rejection
Feedback
Feedforward systems
Harmonic analysis
Harmonic distortion
Inductors
Inverters
Mesh generation
Output feedback
Power electronics, power supplies
Power harmonic filters
Power system harmonics
Rejection
total harmonic distortion (THD)
Voltage control
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The influence of selected control strategies on the level of low-order current harmonic distortion generated by an inverter connected to a distorted grid is investigated through a combination of theoretical and experimental studies. A detailed theoretical analysis, based on the concept of harmonic impedance, establishes the suitability of inductor current feedback versus output current feedback with respect to inverter power quality. Experimental results, obtained from a purpose-built 500-W, three-level, half-bridge inverter with an L-C-L output filter, verify the efficacy of inductor current as the feedback variable, yielding an output current total harmonic distortion (THD) some 29% lower than that achieved using output current feedback. A feed-forward grid voltage disturbance rejection scheme is proposed as a means to further reduce the level of low-order current harmonic distortion. Results obtained from an inverter with inductor current feedback and optimized feed-forward disturbance rejection show a THD of just 3% at full-load, representing an improvement of some 53% on the same inverter with output current feedback and no feed-forward compensation. Significant improvements in THD were also achieved across the entire load range. It is concluded that the use of inductor current feedback and feed-forward voltage disturbance rejection represent cost-effect mechanisms for achieving improved output current quality.
ISSN:0885-8993
1941-0107
DOI:10.1109/TPEL.2005.857557