Abstract
Damping is required in grid-connected LCL-filtered inverters. Due to additional power losses caused by passive elements, active damping is more favorable. As an active damping solution, the single-loop filter-based damping, being directly plugged into the current controller, features no extra sensors and simplicity, and thus it has drawn much attention in LCL-filtered inverters. However, the existing filter-based damping is not very satisfactory because of limited frequency characteristics. For example, the notch filter designed for a low LCL-resonance frequency does not function well for a high resonance frequency owing to its overmuch phase lead, which means that one filter is not sufficient to cover all possible LCL resonance frequencies caused by parameter drifts, indicating unnecessary repetitive designs and poor universality. Thus, this paper proposes a notch-like digital filter-based single-loop active damping method, which covers a wide range of frequencies up to the Nyquist frequency. That is, the proposed is robust against LCL filter parameter drifts and grid impedance variations. Simulation results verify the proposed method.
Original language | English |
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Title of host publication | Proceedings of the IEEE 4th Southern Power Electronics Conference (SPEC 2018) |
Number of pages | 8 |
Place of Publication | Singapore |
Publisher | IEEE Press |
Publication date | Dec 2018 |
Pages | 1-8 |
ISBN (Print) | 978-1-5386-8258-6 |
ISBN (Electronic) | 978-1-5386-8257-9 |
DOIs | |
Publication status | Published - Dec 2018 |
Event | The 4th IEEE Southern Power Electronics Conference, SPEC 2018 - Nanyang Technological University, Singapore Duration: 10 Dec 2018 → 13 Dec 2018 |
Conference
Conference | The 4th IEEE Southern Power Electronics Conference, SPEC 2018 |
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Location | Nanyang Technological University |
Country/Territory | Singapore |
Period | 10/12/2018 → 13/12/2018 |
Keywords
- digital filter
- single-loop damping
- LCL filter
- grid-current feedback
- grid-connected inverters