Inter-cluster Voltage Balancing Control of Modular Multilevel Cascaded Converter Under Unbalanced Grid Voltage
This paper presents a novel inter-cluster direct current (DC) capacitor voltage balancing control scheme for the single-star configured modular multilevel cascaded converter (MMCC)-based static synchronous compensator (STATCOM) under unbalanced grid voltage. The negative-sequence component of grid v...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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IEEE
2022-01-01
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| Series: | Journal of Modern Power Systems and Clean Energy |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/9237074/ |
| _version_ | 1811328187751202816 |
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| author | Oghenewvogaga Oghorada Li Zhang Ayodele Esan Dickson Egbune Julius Uwagboe |
| author_facet | Oghenewvogaga Oghorada Li Zhang Ayodele Esan Dickson Egbune Julius Uwagboe |
| author_sort | Oghenewvogaga Oghorada |
| collection | DOAJ |
| description | This paper presents a novel inter-cluster direct current (DC) capacitor voltage balancing control scheme for the single-star configured modular multilevel cascaded converter (MMCC)-based static synchronous compensator (STATCOM) under unbalanced grid voltage. The negative-sequence component of grid voltage at the point of common connection (PCC) causes unbalanced active power flow in the phase limbs of converter. This leads to the imbalance of DC voltages of the submodule capacitors across the MMCC phases, and consequently, the malfunction of converter. The proposed solution is to inject both negative-sequence current (NSC) and zero-sequence voltage (ZSV) into the phase limbs of MMCC. A quantification factor Q<inf>F</inf> is used to achieve the sharing of intercluster active power between the NSC and ZSV injection methods. Accurate determination of the quantification factor has been presented. In addition to maintaining the DC voltages of sub-module capacitor across the MMCC phases balanced, it also prevents the overcurrent and overvoltage of converter by injecting NSC and ZSV with the right proportion. The control scheme is validated on a 3.54 kV 1.2 MVA power system using MMCC-based STAT-COM with 3-level bridge cells as sub-modules. The results show that the proposed scheme provides superior effectiveness in eliminating the voltage imbalance of DC capacitor in the phase limb while maintaining low voltage and current ratings. |
| first_indexed | 2024-04-13T15:21:53Z |
| format | Article |
| id | doaj.art-1ba8cebcaedd4869926e877780caf0db |
| institution | Directory Open Access Journal |
| issn | 2196-5420 |
| language | English |
| last_indexed | 2024-04-13T15:21:53Z |
| publishDate | 2022-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | Journal of Modern Power Systems and Clean Energy |
| spelling | doaj.art-1ba8cebcaedd4869926e877780caf0db2022-12-22T02:41:39ZengIEEEJournal of Modern Power Systems and Clean Energy2196-54202022-01-0110251552310.35833/MPCE.2019.0001299237074Inter-cluster Voltage Balancing Control of Modular Multilevel Cascaded Converter Under Unbalanced Grid VoltageOghenewvogaga Oghorada0Li Zhang1Ayodele Esan2Dickson Egbune3Julius Uwagboe4Landmark University,Department of Electrical & Information Engineering,Omu-Aran,Kwara State,NigeriaUniversity of Leeds,Leeds,United KingdomLandmark University,Department of Electrical & Information Engineering,Omu-Aran,Kwara State,NigeriaLandmark University,Department of Electrical & Information Engineering,Omu-Aran,Kwara State,NigeriaLandmark University,Department of Electrical & Information Engineering,Omu-Aran,Kwara State,NigeriaThis paper presents a novel inter-cluster direct current (DC) capacitor voltage balancing control scheme for the single-star configured modular multilevel cascaded converter (MMCC)-based static synchronous compensator (STATCOM) under unbalanced grid voltage. The negative-sequence component of grid voltage at the point of common connection (PCC) causes unbalanced active power flow in the phase limbs of converter. This leads to the imbalance of DC voltages of the submodule capacitors across the MMCC phases, and consequently, the malfunction of converter. The proposed solution is to inject both negative-sequence current (NSC) and zero-sequence voltage (ZSV) into the phase limbs of MMCC. A quantification factor Q<inf>F</inf> is used to achieve the sharing of intercluster active power between the NSC and ZSV injection methods. Accurate determination of the quantification factor has been presented. In addition to maintaining the DC voltages of sub-module capacitor across the MMCC phases balanced, it also prevents the overcurrent and overvoltage of converter by injecting NSC and ZSV with the right proportion. The control scheme is validated on a 3.54 kV 1.2 MVA power system using MMCC-based STAT-COM with 3-level bridge cells as sub-modules. The results show that the proposed scheme provides superior effectiveness in eliminating the voltage imbalance of DC capacitor in the phase limb while maintaining low voltage and current ratings.https://ieeexplore.ieee.org/document/9237074/Low-voltage ride through (LVRT)single-star bridge converter (SSBC)static synchronous compensator (STATCOM)modular multilevel cascaded converter (MMCC)quantification factor |
| spellingShingle | Oghenewvogaga Oghorada Li Zhang Ayodele Esan Dickson Egbune Julius Uwagboe Inter-cluster Voltage Balancing Control of Modular Multilevel Cascaded Converter Under Unbalanced Grid Voltage Journal of Modern Power Systems and Clean Energy Low-voltage ride through (LVRT) single-star bridge converter (SSBC) static synchronous compensator (STATCOM) modular multilevel cascaded converter (MMCC) quantification factor |
| title | Inter-cluster Voltage Balancing Control of Modular Multilevel Cascaded Converter Under Unbalanced Grid Voltage |
| title_full | Inter-cluster Voltage Balancing Control of Modular Multilevel Cascaded Converter Under Unbalanced Grid Voltage |
| title_fullStr | Inter-cluster Voltage Balancing Control of Modular Multilevel Cascaded Converter Under Unbalanced Grid Voltage |
| title_full_unstemmed | Inter-cluster Voltage Balancing Control of Modular Multilevel Cascaded Converter Under Unbalanced Grid Voltage |
| title_short | Inter-cluster Voltage Balancing Control of Modular Multilevel Cascaded Converter Under Unbalanced Grid Voltage |
| title_sort | inter cluster voltage balancing control of modular multilevel cascaded converter under unbalanced grid voltage |
| topic | Low-voltage ride through (LVRT) single-star bridge converter (SSBC) static synchronous compensator (STATCOM) modular multilevel cascaded converter (MMCC) quantification factor |
| url | https://ieeexplore.ieee.org/document/9237074/ |
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