Controller Design-oriented Analysis of Grid-forming Converters for Stability Robustness Enhancement

doi:10.23919/CJEE.2021.000036

Chinese Journal of Electrical Engineering ›› 2021, Vol. 7 ›› Issue (4): 37-48.doi: 10.23919/CJEE.2021.000036

• Special Issue Papers • Previous Articles Next Articles

扫码分享

Controller Design-oriented Analysis of Grid-forming Converters for Stability Robustness Enhancement

Yicheng Liao¹, Xiongfei Wang^2,*

1. School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Stockholm 10044, Sweden;
2. AAU Energy, Aalborg University, Aalborg 9220, Denmark

Received:2021-07-27 Revised:2021-10-16 Accepted:2021-11-03 Online:2021-12-25 Published:2022-01-07
Contact: *E-mail: xwa@energy.aau.dk
About author:Yicheng Liao (S'16-M'21) received the B.S. and M.S. degrees in Electrical Engineering from Southwest Jiaotong University, Chengdu, China, in 2015 and 2018, respectively, and the Ph.D. degree in Energy Technology from Aalborg University, Aalborg, Denmark, in 2021.She was a Visiting Student with Ecole Polytechnique and French National Institute for Research in Digital Science and Technology, Paris, France, in July 2017. From September 2018 to July 2021, she was with the AAU Energy, Aalborg University, as a Research Assistant and later on a Postdoc. Since August 2021, she has become a Postdoc with the School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Stockholm, Sweden. Her research interests include the modeling, stability analysis, and control of power electronics-based power systems.Dr. Liao was selected as the 2020 Outstanding Reviewer of IEEE Transactions on Power Electronics and the 2020 Star Reviewer of IEEE Journal of Emerging and Selected Topics in Power Electronics. She was the recipient of the 2020 Top Download Paper Award in IEEE Open Journal of the Industrial Electronics Society and the 2021 Ph.D. Thesis Talk Award in IEEE Power Electronics Society.
Xiongfei Wang (S'10-M'13-SM'17) received the B.S. degree from Yanshan University, Qinhuangdao, China, in 2006, the M.S. degree from Harbin Institute of Technology, Harbin, China, in 2008, both in Electrical Engineering, and the Ph.D. degree in Energy Technology from Aalborg University, Aalborg, Denmark, in 2013. From 2009 he has been with the Department of Energy Technology, Aalborg University, where he became an Assistant Professor in 2014, an Associate Professor in 2016, a Professor and Leader of Electronic Power Grid (eGrid) Research Group in 2018. He is also a Visiting Professor at KTH Royal Institute of Technology, Stockholm, Sweden, from 2020. His current research interests include modeling and control of power electronic converters and systems, stability and power quality of power-electronics-dominated power systems, high-power converters. Dr. Wang serves as a Member-at-Large of Administrative Committee for the IEEE Power Electronics Society (PELS) in 2020-2022, a Co-Editor-in-Chief for the IEEE Transactions on Power Electronics Letters, and as an Associate Editor for the IEEE Journal of Emerging and Selected Topics in Power Electronics (JESTPE). He was selected into Aalborg University Strategic Talent Management Program in 2016. He has received 6 Prize Paper Awards in the IEEE Transactions and conferences, the 2018 Richard M. Bass Outstanding Young Power Electronics Engineer Award, the 2019 IEEE PELS Sustainable Energy Systems Technical Achievement Award, the 2020 IEEE Power & Energy Society Prize Paper Award, the 2020 JESTPE Star Associate Editor Award, and the Highly Cited Researcher in the Web of Science in 2019-2020.

Abstract

Abstract: Grid-forming converters can suffer from control interaction problems in grid connections that can result in small-signal instability. Their inner-loop voltage controller tends to interact with the outer-loop power controller, rendering the controller design more difficult. To conduct a design-oriented analysis, a control-loop decomposition approach for grid-forming converters is proposed. Combined with impedance-based stability analysis, the control-loop decomposition approach can reveal how different control loops affect the converter-grid interaction. This results in a robust controller design enabling grid-forming converters to operate within a wider range of grid short-circuit ratios. Finally, simulation and experimental results, which validate the approach, are presented.

Key words: Grid-forming converters, control-loop interaction, robust control design, small-signal stability, grid connection

Yicheng Liao, Xiongfei Wang. Controller Design-oriented Analysis of Grid-forming Converters for Stability Robustness Enhancement[J]. Chinese Journal of Electrical Engineering, 2021, 7(4): 37-48.

References

[1] B Kroposki, B Johnson, Y Zhang, et al.Achieving a 100% renewable grid: Operating electric power systems with extremely high levels of variable renewable energy.IEEE Power and Energy Mag., 2017, 15(2): 61-73.
[2] R H Lasseter, Z Chen, D Pattabiraman.Grid-forming inverters: A critical asset for the power grid.IEEE J. Emerging Sel. Topics Power Electron., 2020, 8(2): 925-935.
[3] J Rocabert, A Luna, F Blaabjerg, et al.Control of power converters in AC microgrids.IEEE Trans. Power Electron., 2012, 27(11): 4734-4749.
[4] L Zhang, L Harnefors, H Nee.Power-synchronization control of grid-connected voltage-source converters.IEEE Trans. Power Syst., 2010, 25(2): 809-820.
[5] X Wang, M G Taul, H Wu, et al.Grid-synchronization stability of converter-based resources: An overview.IEEE O. J. Ind. Appl., 2020, 1: 115-134.
[6] X Wang, F Blaabjerg.Harmonic stability in power electronic based power systems: Concept, modeling, and analysis.IEEE Trans. Smart Grid, 2019, 10(3): 2858-2870.
[7] J Z Zhou, H Ding, S Fan, et al.Impact of short-circuit ratio and phase-locked-loop parameters on the small-signal behavior of a VSC-HVDC converter.IEEE Trans. Power Del., 2014, 29(5): 2287-2296.
[8] H Liu, X Xie, J He, et al.Subsynchronous interaction between direct-drive PMSG based wind farms and weak AC networks.IEEE Trans. Power Syst., 2017, 32(6): 4708-4720.
[9] L Harnefors, M Bongiorno, S Lundberg.Input-admittance calculation and shaping for controlled voltage-source converters.IEEE Trans. Ind. Electron., 2007, 54(6): 3323-3334.
[10] B Wen, D Dong, D Boroyevich, et al.Impedance-based analysis of grid-synchronization stability for three-phase paralleled converters.IEEE Trans. Power Electron., 2016, 31(1): 26-38.
[11] X Wang, L Harnefors, F Blaabjerg.Unified impedance model of grid-connected voltage-source converters.IEEE Trans. Power Electron., 2018, 33(2): 1775-1787.
[12] G Denis, T Prevost, P Panciatici, et al.Improving robustness against grid stiffness, with internal control of an AC voltage-controlled VSC. in Proc. IEEE Power and Energy Society General Meeting (PESGM), 2016, Boston, MA, 2016: 1-5.
[13] T Qoria, F Gruson, F Colas, et al. Analysis of the coupling between the outer and inner control loops of a grid-forming voltage source converter. in Proc. Europ. Conf. Power Electron. and Appl. (EPE), 2020: 1-10.
[14] S D'Arco, J A Suul, O Fosso.Automatic tuning of cascaded controllers for power converters using eigenvalue parametric sensitivities.IEEE Trans. Ind. Appl., 2015, 51(2): 1743-1753.
[15] E Barklund, N Pogaku, M Prodanovic, et al.Energy management in autonomous microgrid using stability-constrained droop control of inverters.IEEE Trans. Power Electron., 2008, 23(5): 2346-2352.
[16] K Yu, Q Ai, S Wang, et al.Analysis and optimization of droop controller for microgrid system based on small-signal dynamic model.IEEE Trans. Smart Grid, 2016, 7(2): 695-705.
[17] Y Prabowo, V M Iyer, B Kim, et al.Modeling and stability assessment of single-phase droop controlled solid state transformer. in Proc. Inter. Conf. on Power Electron. and ECCE Asia, 2019, Busan, Korea, 2019: 3285-3291.
[18] X Wang, F Blaabjerg, W Wu.Modeling and analysis of harmonic stability in an AC power-electronics-based power system.IEEE Trans. Power Electron., 2014, 29(12): 6421-6432.
[19] L Harnefors, X Wang, A G Yepes, et al.Passivity based stability assessment of grid-connected VSCs: An overview.IEEE J. Emerging Sel. Topics Power Electron., 2016, 4(1): 116-125.
[20] Y Liao, X Wang, F Blaabjerg.Passivity-based analysis and design of linear voltage controllers for voltage-source converters.IEEE O. J. Ind. Electron. Soc., 2020, 1: 114-126.
[21] G Denis.From grid-following to grid-forming: The new strategy to build 100% power electronics interfaced transmission system with enhanced transient behavior. Villeneuve-d'Ascq: Ecole Centrale de Lille, 2017.
[22] S Wang, Z Liu, J Liu, et al.Small-signal modeling and stability prediction of parallel droop-controlled inverters based on terminal characteristics of individual inverters.IEEE Trans. Power Electron., 2020, 35(1): 1045-1063.
[23] W Cao, Y Ma, F Wang, et al.Low-frequency stability analysis of inverter-based islanded multiple-bus AC microgrids based on terminal characteristics.IEEE Trans. Smart Grid, 2020, 11(5): 3662-3676.
[24] F Cavazzana, A Khodamoradi, H Abedini, et al.Analysis of an impedance modeling approach for droop-controlled inverters in system DQ frame. in Proc. IEEE Energy Conversion Congress and Exposition (ECCE), 2019, Baltimore, MD, USA, 2019.
[25] W Wu,Y Chen,L Zhou, et al.Sequence impedance modeling and stability comparative analysis of voltage-controlled VSGs and current-controlled VSGs.IEEE Trans. Ind. Electron., 2019, 66(8): 6460-6472.
[26] Y Liao, X Wang, F Liu, et al.Sub-synchronous control interaction in grid-forming VSCs with droop control. in Proc. IEEE Workshop on the Electronic Grid (eGRID), 2019, Xiamen, China, 2019: 1-6.
[27] K Oue, S Sano, T Kato, et al.Stability analysis of grid-forming inverter in DQ frequency domain. in Proc. IEEE Workshop on Control and Modeling for Power Electronics (COMPEL), 2019, Toronto, ON, Canada, Jun. 2019.
[28] S D'Arco, J A Suul.Equivalence of virtual synchronous machines and frequency-droops for converter-based microgrids.IEEE Trans. Smart Grid, 2014, 5(1): 394-395.
[29] P C Loh, M J Newman, D N Zmood, et al.A comparative analysis of multiloop voltage regulation strategies for single and three-phase UPS systems.IEEE Trans. Power Electron., 2003, 18(5): 1176-1185.
[30] I Postlethwaite.A generalized inverse Nyquist stability criterion.Int. J. Control, 1977, 26(3): 325-340.
[31] J Bao, F Wang, P L Lee, et al.New frequency-domain phase-related properties of MIMO LTI passive systems and robust controller synthesis. in Proc. 13th World Congr. of IFAC, 1996, San Francisco, USA, 1996: 3276-3281.
[32] A J Agbemuko, J L Dominguez-Garcia, O Gomis-Bellmunt, et al. Passivity-based analysis and performance enhancement of a vector controlled VSC connected to a weak ac grid.IEEE Trans. Power Delivery, 2021, 36(1): 156-167.
[33] Y Liao, X Wang.Impedance-based stability analysis for interconnected converter systems with open-loop RHP poles.IEEE Trans. Power Electron., 2020, 35(4): 4388-4397.
[34] M Bongiorno.Challenges and opportunities in power electronics dominated grids.in KTH Workshop on Emerging Topics in Control of Power Systems, 2020.

Controller Design-oriented Analysis of Grid-forming Converters for Stability Robustness Enhancement

PDF

Knowledge

Abstract

Cite this article

share this article

References

Related Articles 4

Recommended Articles

Metrics

Comments

[1]	Yuxi Men, Yuhua Du, Xiaonan Lu. Distributed Control Framework and Scalable Small-signal Stability Analysis for Dynamic Microgrids [J]. Chinese Journal of Electrical Engineering, 2021, 7(4): 49-59.
[2]	ZHU Zuobin,HUANG Shaoping,LI Zhenxing,XIAO Yinan. Research on Off Grid / Grid Switching Control Strategy of Micro-grid Power Converter System [J]. Journal of Electrical Engineering, 2019, 14(2): 92-96.
[3]	Guoen Cao, Kai Sun, Siyue Jiang, Shilei Lu, Yibo Wang. A Modular DC/DC Photovoltic Generation System for HVDC Grid Connection [J]. Chinese Journal of Electrical Engineering, 2018, 4(2): 56-64.
[4]	Chen Feng,Ying Hong,Xu Kunpeng,Zhang Haibo,Hu Xiaoyue. Research on Grid Connected Seamless Switching Technology of Multi-Level Parallel Connection of Ship's Shore Power Supply [J]. Journal of Electrical Engineering, 2017, 12(4): 33-37.