Experimental Investigation of the Frequency Response of an LC-Filter and Power Transformer for Grid Connection
The power delivered by a voltage source inverter needs to be filtered to fulfill grid code requirements. A commonly used filter technology is the LCL-filter. An issue with the LCL-filter is the occurrence of a resonance peak, which can be mitigated with active or passive damping methods. The transfe...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-08-01
|
| Series: | Energies |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1073/16/15/5784 |
| _version_ | 1797586827618549760 |
|---|---|
| author | Christoffer Fjellstedt Johan Forslund Karin Thomas |
| author_facet | Christoffer Fjellstedt Johan Forslund Karin Thomas |
| author_sort | Christoffer Fjellstedt |
| collection | DOAJ |
| description | The power delivered by a voltage source inverter needs to be filtered to fulfill grid code requirements. A commonly used filter technology is the LCL-filter. An issue with the LCL-filter is the occurrence of a resonance peak, which can be mitigated with active or passive damping methods. The transfer function of the filter is often used to investigate the frequency response of the system and propose damping methods. The use of an LC-filter combined with a power transformer to form an LCL-filter has not been extensively investigated. Therefore, the study in this article introduces a model for an LC-filter and power transformer for the grid connection and a derived transfer function for the model. The transfer function for the system is validated with simulations and experimental investigations. The results from simulations and the results from a direct solution of the derived analytical function overlap almost perfectly. The magnitudes of the experimental results are approximately 1 dB lower than the simulation and analytical results before the resonance frequency. At the resonance frequency, the experimental results are approximately 13.4 dB lower. The resonance frequency, however, occurs at approximately the same frequency. It is also concluded that the system is significantly damped. |
| first_indexed | 2024-03-11T00:28:41Z |
| format | Article |
| id | doaj.art-b5e471b80e484ea887664f052ac5327a |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-11T00:28:41Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-b5e471b80e484ea887664f052ac5327a2023-11-18T22:52:46ZengMDPI AGEnergies1996-10732023-08-011615578410.3390/en16155784Experimental Investigation of the Frequency Response of an LC-Filter and Power Transformer for Grid ConnectionChristoffer Fjellstedt0Johan Forslund1Karin Thomas2Division of Electricity, Department of Electrical Engineering, Uppsala University, 752 37 Uppsala, SwedenDivision of Electricity, Department of Electrical Engineering, Uppsala University, 752 37 Uppsala, SwedenDivision of Electricity, Department of Electrical Engineering, Uppsala University, 752 37 Uppsala, SwedenThe power delivered by a voltage source inverter needs to be filtered to fulfill grid code requirements. A commonly used filter technology is the LCL-filter. An issue with the LCL-filter is the occurrence of a resonance peak, which can be mitigated with active or passive damping methods. The transfer function of the filter is often used to investigate the frequency response of the system and propose damping methods. The use of an LC-filter combined with a power transformer to form an LCL-filter has not been extensively investigated. Therefore, the study in this article introduces a model for an LC-filter and power transformer for the grid connection and a derived transfer function for the model. The transfer function for the system is validated with simulations and experimental investigations. The results from simulations and the results from a direct solution of the derived analytical function overlap almost perfectly. The magnitudes of the experimental results are approximately 1 dB lower than the simulation and analytical results before the resonance frequency. At the resonance frequency, the experimental results are approximately 13.4 dB lower. The resonance frequency, however, occurs at approximately the same frequency. It is also concluded that the system is significantly damped.https://www.mdpi.com/1996-1073/16/15/5784LC-filterLCL-filterpower transformergrid connectionrenewable energy |
| spellingShingle | Christoffer Fjellstedt Johan Forslund Karin Thomas Experimental Investigation of the Frequency Response of an LC-Filter and Power Transformer for Grid Connection Energies LC-filter LCL-filter power transformer grid connection renewable energy |
| title | Experimental Investigation of the Frequency Response of an LC-Filter and Power Transformer for Grid Connection |
| title_full | Experimental Investigation of the Frequency Response of an LC-Filter and Power Transformer for Grid Connection |
| title_fullStr | Experimental Investigation of the Frequency Response of an LC-Filter and Power Transformer for Grid Connection |
| title_full_unstemmed | Experimental Investigation of the Frequency Response of an LC-Filter and Power Transformer for Grid Connection |
| title_short | Experimental Investigation of the Frequency Response of an LC-Filter and Power Transformer for Grid Connection |
| title_sort | experimental investigation of the frequency response of an lc filter and power transformer for grid connection |
| topic | LC-filter LCL-filter power transformer grid connection renewable energy |
| url | https://www.mdpi.com/1996-1073/16/15/5784 |
| work_keys_str_mv | AT christofferfjellstedt experimentalinvestigationofthefrequencyresponseofanlcfilterandpowertransformerforgridconnection AT johanforslund experimentalinvestigationofthefrequencyresponseofanlcfilterandpowertransformerforgridconnection AT karinthomas experimentalinvestigationofthefrequencyresponseofanlcfilterandpowertransformerforgridconnection |