Method to Extend the Small-Signal Stability Power Boundary of GCI Considering PLL Effects Under Weak Grid
Source abstract
Abstract
Renewable energy is being increasingly integrated into power grids. As a result, the three-phase grid-connected inverter (GCI) faces power transfer limitations caused by small-signal stability issues. To improve energy utilization and enhance stability, this paper employs an impedance-based method to analyze the small-signal stability power boundary of the GCI. This boundary is then quantified using the generalized Nyquist criterion (GNC). Our analysis reveals that the power boundary decreases as the grid short-circuit ratio (SCR) decreases or the phase-locked loop (PLL) bandwidth increases. To address this problem, we propose an impedance reshaping method that cancels the negative resistance effect introduced by PLL feedforward. This approach raises the small-signal stability power limit to the rated power and ensures stable operation under grid impedance variations and high PLL bandwidth. Finally, impedance analysis and experimental verification confirm both the theoretical correctness and the practical effectiveness of the proposed method in extending the stability power boundary.
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Research context
OpenAlex topics: Microgrid Control and Optimization · Power System Optimization and Stability · Wind Turbine Control Systems
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Affiliations
College of Information Science and Engineering, Northeastern University, Shenyang 110819, China
References (34)
Show source-provided references
1. Power System Stability with High Penetration of Renewable Energy Sources: Challenges, Assessment, and Mitigation Strategies10.1109/ACCESS.2025.3546491 ↗
2. Large-Scale Renewable Energy Transmission by HVDC: Challenges and Proposals10.1016/j.eng.2022.04.017 ↗
3. Bryant, J.S., McGrath, B., Meegahapola, L., and Sokolowski, P. (2021). Small-Signal Stability Analysis of Voltage Source Inverters Operating under Low Short-Circuit Ratios. 2021 IEEE Madrid PowerTech, IEEE.10.1109/PowerTech46648.2021.9494811 ↗
4. A Current Controller Gain Characterization of Weak Grid Coupled Solar Inverter Through Impedance Interaction Modeling10.1109/TIE.2022.3170633 ↗
5. Analysis of Middle Frequency Resonance in DFIG System Considering Phase-Locked Loop10.1109/TPEL.2017.2672867 ↗
6. Real-World Subsynchronous Oscillation Events in Power Grids with High Penetrations of Inverter-Based Resources10.1109/TPWRS.2022.3161418 ↗
7. Stability Analysis of the Grid-Connected Inverter Considering the Asymmetric Positive-Feedback Loops Introduced by the PLL in Weak Grids10.1109/TIE.2021.3086716 ↗
8. A Tight Grid-Forming Control Framework for Grid-Connected Inverters Under Large Grid Frequency Drops with Wide Range of SCR and X/R10.1109/TPEL.2025.3643503 ↗
9. Voltage Support Strategy for Improving Power Transfer Capability of Grid-Connected Converter Under Unbalanced Conditions10.1109/TPEL.2024.3380626 ↗
10. Stability Analysis of the Grid-Tied VSC Considering the Influence of Short Circuit Ratio and X/R
11. Huang, L., Wu, C., Zhou, D., and Blaabjerg, F. (2021). Impact of Grid Strength and Impedance Characteristics on the Maximum Power Transfer Capability of Grid-Connected Inverters. Appl. Sci., 11.10.3390/app11094288 ↗
12. Impedance-compensated grid synchronisation for extending the stability range of weak grids with voltage source converters10.1049/iet-gtd.2015.0879 ↗
13. Small-Signal Stability Analysis of Offshore AC Network Having Multiple VSC-HVDC Systems10.1109/TPWRD.2017.2725982 ↗
14. Impedance-Based Analysis of Interconnected Power Electronics Systems: Impedance Network Modeling and Comparative Studies of Stability Criteria10.1109/JESTPE.2019.2914560 ↗
15. Unified Impedance Model of Grid-Connected Voltage-Source Converters10.1109/TPEL.2017.2684906 ↗
16. Capacitor-Voltage Feedforward with Full Delay Compensation to Improve Weak Grids Adaptability of LCL-Filtered Grid-Connected Converters for Distributed Generation Systems10.1109/TPEL.2017.2665483 ↗
17. Impedance-Based Analysis of Digital Control Delay in Grid-Tied Voltage Source Inverters10.1109/TPEL.2020.2987198 ↗
18. Constant-Coupling-Effect-Based PLL for Synchronization Stability Enhancement of Grid-Connected Converter Under Weak Grids10.1109/TIE.2022.3227268 ↗
19. Impedance-Phase and Magnitude Control Method to Improve Stability of Grid-Connected Inverters in Weak Grid
20. Zhang, Y., Pen, H., and Zhang, X. (2024). Stability Control of Grid-Connected Converter Considering Phase-Locked Loop Frequency Coupling Effect. Energies, 17.10.3390/en17143438 ↗
21. Stability Improvement for Three-Phase Grid-Connected Converters Through Impedance Reshaping in Quadrature-Axis10.1109/TPEL.2017.2777972 ↗
22. The Control Strategy for the Grid-Connected Inverter Through Impedance Reshaping in q-Axis and its Stability Analysis Under a Weak Grid10.1109/JESTPE.2020.3024863 ↗
23. Improving Small-Signal Stability of Grid-Connected Inverter Under Weak Grid by Decoupling Phase-Lock Loop and Grid Impedance10.1109/TIE.2021.3095791 ↗
24. Improved Weak Grids Synchronization Unit for Passivity Enhancement of Grid-Connected Inverter10.1109/JESTPE.2022.3168655 ↗
25. Harmonic Instability and Amplification for Grid-Connected Inverter with Voltage Harmonics Compensation Considering Phase-Locked Loop10.1109/JESTPE.2019.2936257 ↗
26. PCC Voltage Perturbation Path Analysis and Compensation for Grid-Connected Voltage-Source Converter Under Weak Grid10.1109/TIE.2020.3045593 ↗
27. A Passivity-Based Weighted Proportional-Derivative Feedforward Scheme for Grid-Connected Inverters with Enhanced Harmonic Rejection Ability10.1109/JESTPE.2021.3121410 ↗
28. Robust Technique Using the Optimized Grid Voltage Feedforward to Conquer the Impact Induced by Dual Factors for Grid-Connected Inverter in Weak Grid10.1109/TIE.2023.3299011 ↗
29. Huang, L., Wu, C., Zhou, D., and Blaabjerg, F. (2021). Comparison of Three Small-Signal Stability Analysis Methods for Grid-Following Inverter. 2021 International Aegean Conference on Electrical Machines and Power Electronics (ACEMP) & 2021 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM), IEEE.10.1109/OPTIM-ACEMP50812.2021.9590036 ↗
30. Impedance-Based Stability Criterion for Grid-Connected Inverters10.1109/TPEL.2011.2136439 ↗
31. Analysis of D-Q Small-Signal Impedance of Grid-Tied Inverters10.1109/TPEL.2015.2398192 ↗
32. Aggregated-Impedance-Based Stability Analysis for a Parallel-Converter System Considering the Coupling Effect of Voltage Feedforward Control and Reactive Power Injection10.1109/TPEL.2020.3031342 ↗
33. Passivity-Based Analysis and Performance Enhancement of a Vector Controlled VSC Connected to a Weak AC Grid10.1109/TPWRD.2020.2982498 ↗
34. Mechanism Analysis and Stabilization of Three-Phase Grid-Inverter Systems Considering Frequency Coupling