Title |
Low Frequency Current Reduction using a Quasi-Notch Filter operated in Two-Stage DC-DC-AC Grid-Connected Systems |
Authors |
Hong-Ju Jung and Rae-Young Kim ; |
DOI |
10.6113/TKPE/2014.19.3.276 |
Keywords |
dc-dc-ac converter; dc-link voltage regulation; quasi-notch filter; double-fundamental frequency |
Abstract |
In a single-phase grid-connected power system consisting of a dc-dc converter and a dc-ac converter, the current drawn from renewable energy sources has a tendency to be pulsated and contains double-fundamental frequency ripple components, which results in several drawback such as a power harvesting loss and a shortening of the energy source’s life. This paper presents a new double-fundamental current reduction- scheme with a fast dc-link voltage loop for two-stage dc-dc-ac grid connected systems. In the frequency domain, an adequate control design is performed based on the small-signal transfer function of a two-stage dc-dc-ac converter. To verify the effectiveness of proposed control algorithm, a 1 kW hardware prototype has been built and experimental results are presented. |