The Current Limiting Method for a Power Inverter Operating in the Grid Forming Mode
Keywords:
power inverter, automatic control system, current saturation algorithm, virtual synchronous generator
Abstract
One important line in the development of modern power systems involves the use of a constantly increasing number of power converters to provide system services through their operation in a grid-forming mode. One possible implementation of this concept is a control algorithm based on a virtual synchronous generator (VSG). However, the problem of VSG operation under abnormal conditions related to increased output current remains unresolved. The existing current limitation methods on the basis of a so-called current saturation algorithm (CSA) either lead to the loss of grid-forming properties or reduce the possible current output range in the limiting mode. In this regard, the article proposes to use a VSG structure with a controlled current reference signal (CC-VSG) instead of conventional reference voltage-controlled VSGs. To limit the current, the CC-VSG incorporates a current vector amplitude limiter. In that case, the output current phase continues to be regulated based on the currently emerging conditions in the grid due to the voltage feedback in the virtual synchronous machine equations. The article presents the results of physical testing of an experimental inverter prototype with the CC-VSG and CSA, as well as its comparison with a commercial hybrid inverter. It has been proven that the proposed solutions make it possible to limit the current in both islanded and grid-connected modes while ensuring stable operation and reliable power supply to the load.
References
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13. Erdocia J., Urtasun A., Marroyo L. Dual Voltage–Current Control to Provide Grid-Forming Inverters With Current Limiting Capability. – IEEE Journal of Emerging and Selected Topics in Power Electronics, 2021, 3950–3962, DOI: 10.1109/JESTPE.2021.3133806.
14. Bottrell N., Green T.C. Comparison of Current-Limiting Strategies During Fault Ride-Through of Inverters to Prevent Latch-Up and Wind-Up. – IEEE Transactions on Power Electronics, 2014, vol. 29, No. 7, pp. 3786–3797, DOI: 10.1109/TPEL.2013.2279162.
15. Teodorescu R. et al. A New Control Structure for Grid-Connected LCL PV Inverters with Zero Steady-State Error and Selective Harmonic Compensation. – 19th Annual IEEE Applied Power Electronics Conference and Exposition, 2004, DOI: 10.1109/APEC.2004.1295865.
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18. Gkountaras A., Dieckerhoff S., Sezi T. Evaluation of Current Limiting Methods for Grid Forming Inverters in Medium Voltage Microgrids. – IEEE Energy Conversion Congress and Exposition (ECCE), 2015, pp. 1223–1230, DOI: 10.1109/ECCE.2015.7309831.
19. Fan L. Modeling Type-4 Wind in Weak Grids. – IEEE Transactions on Sustainable Energy, 2019, vol. 10, No. 2, pp. 853–864, DOI: 10.1109/TSTE.2018.2849849.
20. Xin H. et al. Synchronous Instability Mechanism of P-f Dro-op-Controlled Voltage Source Converter Caused by Current Saturation. – IEEE Transactions on Power Systems, 2016, vol. 31, No. 6, pp. 5206–5207, DOI: 10.1109/TPWRS.2016.2521325.
21. Rokrok E. et al. Transient Stability Assessment and Enhancement of Grid-Forming Converters Embedding Current Reference Saturation as Current Limiting Strategy. – IEEE Transactions on Power Systems, 2022, vol. 37, No. 2, pp. 1519–1531, DOI: 10.1109/TPWRS.2021.3107959.
22. Илюшин П.В., Симонов А.В. О функционировании распределенных источников энергии с силовыми преобразователями в составе энергосистем и изолированных энергорайонов. – Релейная защита и автоматизация, 2020, № 2 (39), с. 30–38.
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Работа выполнена в рамках Программы стратегического академического лидерства «Приоритет - 2030» ТПУ (№ Приоритет-2030-ЭЭЗЦ-015-198-2025).
#
1. Voropay N.I. Elektrichestvo – in Russ. (Electricity), 2020, No. 7, pp. 12–21.
2. Kroposki B. et al. Achieving a 100% Renewable Grid: Operating Electric Power Systems with Extremely High Levels of Variable Renewable Energy. – IEEE Power and Energy Magazine, 2017, vol. 15, No. 2, pp. 61–73, DOI: 10.1109/MPE.2016.2637122.
3. Hatziargyriou N. et al. Definition and Classification of Power System Stability – Revisited & Extended. – IEEE Transactions on Power Systems, 2021, vol. 36, No. 4, pp. 3271–3281, DOI: 10.1109/TPWRS.2020.3041774.
4. North American Electric Reliability Corporation (NERC). Grid Forming Functional Specifications for BPS-Connected Battery Energy Storage Systems, 2023 [Electron. resource], URL: https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_GFM_Functional_Specification.pdf (Accessed on 15.06.25).
5. Australian Energy Market Operator (AEMO). Voluntary Specifications for Grid-Fomring Inverters, 2023 [Electron. resource], URL: https://aemo.com.au/-/media/files/initiatives/ primary-frequency-response/2023/gfm-voluntary-spec.pdf (Accessed on 15.06.25).
6. EU. Migrate consortium – 2020 [Electron. resource], URL: https://www. h2020-migrate.eu/ (Accessed on 15.06.25).
7. Suvorov A.A. et al. Elektricheskie stantsii – in Russ. (Electrical Stations), 2022, No. 3 (1088), pp. 43–57.
8. Lin Y. et al. Research Roadmap on Grid-Forming Inverters. Technical Report NREL/TP-5D00-73476, 2020, 60 p.
9. Fan B. et al. A Review of Current-Limiting Control of Grid-Forming Inverters Under Symmetrical Disturbances. – IEEE Open Journal of Power Electronics, 2022, vol. 3, pp. 955–969, DOI: 10.1109/OJPEL.2022.3227507.
10. Lu M. et al. Dispatchable Virtualoscillator-Controlled Inverters with Current-Limiting and MPPT Capabilities. – IEEE Energy Conversion Congress and Exposition (ECCE), 2021, pp. 3316–3323, DOI: 10.1109/ECCE47101.2021.9595530.
11. Du W., Mohiuddin S.M. A Two-Stage Current Limiting Control Strategy for Improved Low-Voltage Ride-Through Capability of Direct-Droop-Controlled, Grid-Forming Inverters. – IEEE Energy Conversion Congress and Exposition (ECCE), 2023, pp. 2886–2890, DOI: 10.1109/ECCE53617.2023.10362015.
12. Li Z., Hu J., Chan K.W. A New Current Limiting and Overload Protection Scheme for Distributed Inverters in Microgrids Under Grid Faults. – IEEE Transactions on Industry Applications, 2021, vol. 57, No. 6, pp. 6362–6374, DOI: 10.1109/TIA.2021.3104269.
13. Erdocia J., Urtasun A., Marroyo L. Dual Voltage–Current Control to Provide Grid-Forming Inverters With Current Limiting Capability. – IEEE Journal of Emerging and Selected Topics in Power Electronics, 2021, 3950–3962, DOI: 10.1109/JESTPE.2021.3133806.
14. Bottrell N., Green T.C. Comparison of Current-Limiting Strategies During Fault Ride-Through of Inverters to Prevent Latch-Up and Wind-Up. – IEEE Transactions on Power Electronics, 2014, vol. 29, No. 7, pp. 3786–3797, DOI: 10.1109/TPEL.2013.2279162.
15. Teodorescu R. et al. A New Control Structure for Grid-Connected LCL PV Inverters with Zero Steady-State Error and Selective Harmonic Compensation. – 19th Annual IEEE Applied Po-wer Electronics Conference and Exposition, 2004, DOI: 10.1109/APEC.2004.1295865.
16. Askarov A.B. et al. Elektrichestvo – in Russ. (Electricity), 2024, No. 1, pp. 18–36.
17. Suvorov A.A. et al. Elektrichestvo – in Russ. (Electricity), 2023, No. 3, pp. 35–51.
18. Gkountaras A., Dieckerhoff S., Sezi T. Evaluation of Current Limiting Methods for Grid Forming Inverters in Medium Voltage Microgrids. – IEEE Energy Conversion Congress and Exposition (ECCE), 2015, pp. 1223–1230, DOI: 10.1109/ECCE.2015.7309831.
19. Fan L. Modeling Type-4 Wind in Weak Grids. – IEEE Transactions on Sustainable Energy, 2019, vol. 10, No. 2, pp. 853–864, DOI: 10.1109/TSTE.2018.2849849.
20. Xin H. et al. Synchronous Instability Mechanism of P-f Droop-Controlled Voltage Source Converter Caused by Current Saturation. – IEEE Transactions on Power Systems, 2016, vol. 31, No. 6, pp. 5206–5207, DOI: 10.1109/TPWRS.2016.2521325.
21. Rokrok E. et al. Transient Stability Assessment and Enhancement of Grid-Forming Converters Embedding Current Reference Saturation as Current Limiting Strategy. – IEEE Transactions on Power Systems, 2022, vol. 37, No. 2, pp. 1519–1531, DOI: 10.1109/TPWRS.2021.3107959.
22. Ilyushin P.V., Simonov A.V. Releynaya zashchita i avtomatizatsiya – in Russ. (Relay Protection and Automation), 2020, No. 2 (39), pp. 30–38
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This study was carried out within the framework of the Tomsk Polytechnic University Strategic Academic Leadership Program "Priority-2030" (No. Priority-2030-EEZTs-015-198-2025).
2. Kroposki B. et al. Achieving a 100% Renewable Grid: Operating Electric Power Systems with Extremely High Levels of Variable Renewable Energy. – IEEE Power and Energy Magazine, 2017, vol. 15, No. 2, pp. 61–73, DOI: 10.1109/MPE.2016.2637122.
3. Hatziargyriou N. et al. Definition and Classification of Power System Stability – Revisited & Extended. – IEEE Transactions on Power Systems, 2021, vol. 36, No. 4, pp. 3271–3281, DOI: 10.1109/TPWRS.2020.3041774.
4. North American Electric Reliability Corporation (NERC). Grid Forming Functional Specifications for BPS-Connected Battery Energy Storage Systems, 2023 [Электрон. ресурс], URL: https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_GFM_Functional_Specification.pdf (дата обращения 15.06.25).
5. Australian Energy Market Operator (AEMO). Voluntary Specifications for Grid-Fomring Inverters, 2023 [Электрон. ресурс], URL: https://aemo.com.au/-/media/files/initiatives/ primary-frequency-response/2023/gfm-voluntary-spec.pdf (дата обращения 15.06.25).
6. EU. Migrate consortium – 2020 [Электрон. ресурс], URL: https://www. h2020-migrate.eu/ (дата обращения 15.06.25).
7. Суворов А.А. и др. Синтез и тестирование типовых структур систем автоматического управления на основе виртуального синхронного генератора для генерирующих установок с силовым преобразователем. – Электрические станции, 2022, № 3 (1088), с. 43–57.
8. Lin Y. et al. Research Roadmap on Grid-Forming Inverters. Technical Report NREL/TP-5D00-73476, 2020, 60 p.
9. Fan B. et al. A Review of Current-Limiting Control of Grid-Forming Inverters Under Symmetrical Disturbances. – IEEE Open Journal of Power Electronics, 2022, vol. 3, pp. 955–969, DOI: 10.1109/OJPEL.2022.3227507.
10. Lu M. et al. Dispatchable Virtualoscillator-Controlled Inverters with Current-Limiting and MPPT Capabilities. – IEEE Energy Conversion Congress and Exposition (ECCE), 2021, pp. 3316–3323, DOI: 10.1109/ECCE47101.2021.9595530.
11. Du W., Mohiuddin S.M. A Two-Stage Current Limiting Control Strategy for Improved Low-Voltage Ride-Through Capability of Direct-Droop-Controlled, Grid-Forming Inverters. – IEEE Energy Conversion Congress and Exposition (ECCE), 2023, pp. 2886–2890, DOI: 10.1109/ECCE53617.2023.10362015.
12. Li Z., Hu J., Chan K.W. A New Current Limiting and Overload Protection Scheme for Distributed Inverters in Microgrids Under Grid Faults. – IEEE Transactions on Industry Applications, 2021, vol. 57, No. 6, pp. 6362–6374, DOI: 10.1109/TIA.2021.3104269.
13. Erdocia J., Urtasun A., Marroyo L. Dual Voltage–Current Control to Provide Grid-Forming Inverters With Current Limiting Capability. – IEEE Journal of Emerging and Selected Topics in Power Electronics, 2021, 3950–3962, DOI: 10.1109/JESTPE.2021.3133806.
14. Bottrell N., Green T.C. Comparison of Current-Limiting Strategies During Fault Ride-Through of Inverters to Prevent Latch-Up and Wind-Up. – IEEE Transactions on Power Electronics, 2014, vol. 29, No. 7, pp. 3786–3797, DOI: 10.1109/TPEL.2013.2279162.
15. Teodorescu R. et al. A New Control Structure for Grid-Connected LCL PV Inverters with Zero Steady-State Error and Selective Harmonic Compensation. – 19th Annual IEEE Applied Power Electronics Conference and Exposition, 2004, DOI: 10.1109/APEC.2004.1295865.
16. Аскаров А.Б. и др. Улучшение демпфирующих свойств виртуального синхронного генератора с помощью корректирующего согласно-параллельного регулятора. – Электричество, 2024, № 1, с. 18–36.
17. Суворов А.А. и др. Управление сетевым инвертором на основе виртуального синхронного генератора при изменении плотности электрической сети. – Электричество, 2023, № 3, с. 35–51.
18. Gkountaras A., Dieckerhoff S., Sezi T. Evaluation of Current Limiting Methods for Grid Forming Inverters in Medium Voltage Microgrids. – IEEE Energy Conversion Congress and Exposition (ECCE), 2015, pp. 1223–1230, DOI: 10.1109/ECCE.2015.7309831.
19. Fan L. Modeling Type-4 Wind in Weak Grids. – IEEE Transactions on Sustainable Energy, 2019, vol. 10, No. 2, pp. 853–864, DOI: 10.1109/TSTE.2018.2849849.
20. Xin H. et al. Synchronous Instability Mechanism of P-f Dro-op-Controlled Voltage Source Converter Caused by Current Saturation. – IEEE Transactions on Power Systems, 2016, vol. 31, No. 6, pp. 5206–5207, DOI: 10.1109/TPWRS.2016.2521325.
21. Rokrok E. et al. Transient Stability Assessment and Enhancement of Grid-Forming Converters Embedding Current Reference Saturation as Current Limiting Strategy. – IEEE Transactions on Power Systems, 2022, vol. 37, No. 2, pp. 1519–1531, DOI: 10.1109/TPWRS.2021.3107959.
22. Илюшин П.В., Симонов А.В. О функционировании распределенных источников энергии с силовыми преобразователями в составе энергосистем и изолированных энергорайонов. – Релейная защита и автоматизация, 2020, № 2 (39), с. 30–38.
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Работа выполнена в рамках Программы стратегического академического лидерства «Приоритет - 2030» ТПУ (№ Приоритет-2030-ЭЭЗЦ-015-198-2025).
#
1. Voropay N.I. Elektrichestvo – in Russ. (Electricity), 2020, No. 7, pp. 12–21.
2. Kroposki B. et al. Achieving a 100% Renewable Grid: Operating Electric Power Systems with Extremely High Levels of Variable Renewable Energy. – IEEE Power and Energy Magazine, 2017, vol. 15, No. 2, pp. 61–73, DOI: 10.1109/MPE.2016.2637122.
3. Hatziargyriou N. et al. Definition and Classification of Power System Stability – Revisited & Extended. – IEEE Transactions on Power Systems, 2021, vol. 36, No. 4, pp. 3271–3281, DOI: 10.1109/TPWRS.2020.3041774.
4. North American Electric Reliability Corporation (NERC). Grid Forming Functional Specifications for BPS-Connected Battery Energy Storage Systems, 2023 [Electron. resource], URL: https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_GFM_Functional_Specification.pdf (Accessed on 15.06.25).
5. Australian Energy Market Operator (AEMO). Voluntary Specifications for Grid-Fomring Inverters, 2023 [Electron. resource], URL: https://aemo.com.au/-/media/files/initiatives/ primary-frequency-response/2023/gfm-voluntary-spec.pdf (Accessed on 15.06.25).
6. EU. Migrate consortium – 2020 [Electron. resource], URL: https://www. h2020-migrate.eu/ (Accessed on 15.06.25).
7. Suvorov A.A. et al. Elektricheskie stantsii – in Russ. (Electrical Stations), 2022, No. 3 (1088), pp. 43–57.
8. Lin Y. et al. Research Roadmap on Grid-Forming Inverters. Technical Report NREL/TP-5D00-73476, 2020, 60 p.
9. Fan B. et al. A Review of Current-Limiting Control of Grid-Forming Inverters Under Symmetrical Disturbances. – IEEE Open Journal of Power Electronics, 2022, vol. 3, pp. 955–969, DOI: 10.1109/OJPEL.2022.3227507.
10. Lu M. et al. Dispatchable Virtualoscillator-Controlled Inverters with Current-Limiting and MPPT Capabilities. – IEEE Energy Conversion Congress and Exposition (ECCE), 2021, pp. 3316–3323, DOI: 10.1109/ECCE47101.2021.9595530.
11. Du W., Mohiuddin S.M. A Two-Stage Current Limiting Control Strategy for Improved Low-Voltage Ride-Through Capability of Direct-Droop-Controlled, Grid-Forming Inverters. – IEEE Energy Conversion Congress and Exposition (ECCE), 2023, pp. 2886–2890, DOI: 10.1109/ECCE53617.2023.10362015.
12. Li Z., Hu J., Chan K.W. A New Current Limiting and Overload Protection Scheme for Distributed Inverters in Microgrids Under Grid Faults. – IEEE Transactions on Industry Applications, 2021, vol. 57, No. 6, pp. 6362–6374, DOI: 10.1109/TIA.2021.3104269.
13. Erdocia J., Urtasun A., Marroyo L. Dual Voltage–Current Control to Provide Grid-Forming Inverters With Current Limiting Capability. – IEEE Journal of Emerging and Selected Topics in Power Electronics, 2021, 3950–3962, DOI: 10.1109/JESTPE.2021.3133806.
14. Bottrell N., Green T.C. Comparison of Current-Limiting Strategies During Fault Ride-Through of Inverters to Prevent Latch-Up and Wind-Up. – IEEE Transactions on Power Electronics, 2014, vol. 29, No. 7, pp. 3786–3797, DOI: 10.1109/TPEL.2013.2279162.
15. Teodorescu R. et al. A New Control Structure for Grid-Connected LCL PV Inverters with Zero Steady-State Error and Selective Harmonic Compensation. – 19th Annual IEEE Applied Po-wer Electronics Conference and Exposition, 2004, DOI: 10.1109/APEC.2004.1295865.
16. Askarov A.B. et al. Elektrichestvo – in Russ. (Electricity), 2024, No. 1, pp. 18–36.
17. Suvorov A.A. et al. Elektrichestvo – in Russ. (Electricity), 2023, No. 3, pp. 35–51.
18. Gkountaras A., Dieckerhoff S., Sezi T. Evaluation of Current Limiting Methods for Grid Forming Inverters in Medium Voltage Microgrids. – IEEE Energy Conversion Congress and Exposition (ECCE), 2015, pp. 1223–1230, DOI: 10.1109/ECCE.2015.7309831.
19. Fan L. Modeling Type-4 Wind in Weak Grids. – IEEE Transactions on Sustainable Energy, 2019, vol. 10, No. 2, pp. 853–864, DOI: 10.1109/TSTE.2018.2849849.
20. Xin H. et al. Synchronous Instability Mechanism of P-f Droop-Controlled Voltage Source Converter Caused by Current Saturation. – IEEE Transactions on Power Systems, 2016, vol. 31, No. 6, pp. 5206–5207, DOI: 10.1109/TPWRS.2016.2521325.
21. Rokrok E. et al. Transient Stability Assessment and Enhancement of Grid-Forming Converters Embedding Current Reference Saturation as Current Limiting Strategy. – IEEE Transactions on Power Systems, 2022, vol. 37, No. 2, pp. 1519–1531, DOI: 10.1109/TPWRS.2021.3107959.
22. Ilyushin P.V., Simonov A.V. Releynaya zashchita i avtomatizatsiya – in Russ. (Relay Protection and Automation), 2020, No. 2 (39), pp. 30–38
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This study was carried out within the framework of the Tomsk Polytechnic University Strategic Academic Leadership Program "Priority-2030" (No. Priority-2030-EEZTs-015-198-2025).
Published
2025-09-29
Section
Article
