Stability Assessment of Current Controller with Harmonic Compensator for LCL-Filtered Grid-Connected Inverter under Distorted Weak Grid
Source abstract
Abstract
An assessment of the stability and performance of current controllers with harmonic compensators is presented for an inductive-capacitive-inductive (LCL)-filtered grid-connected inverter under distorted weak grid conditions. By using two typical current control schemes which are the direct current controller with the capacitor current-based active damping and integral-resonant state feedback current controller, the closed-loop system stability and current control performance are investigated in the presence of both uncertain grid impedance and distorted grid. Even though the controller stability has been investigated under weak grid in several studies, the stability assessment of the entire current control scheme, including the harmonic resonant controllers, still needs a further comprehensive investigation. The system stability is analyzed by obtaining the movement of the closed-loop poles in the discrete-time domain when the grid impedance varies. To fully study the impact of distorted weak grid condition on the LCL filters, three LCL filter parameter sets giving the resonance frequency in different frequency bands are chosen for the purpose of evaluating the system robustness and grid-injected current quality. In order to support the presented theoretical analyses, comprehensive simulation and experimental results based on 32-bit DSP TMS320F28335 to control 2 kVA grid-connected inverter are presented in terms of grid current quality and control stability in the environment of both uncertain grid impedance and distorted grid.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Microgrid Control and Optimization · HVDC Systems and Fault Protection · Islanding Detection in Power Systems
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Electrical and Information Engineering, Seoul National University of Science and Technology, 232 Gongneung-ro, Nowon-gu, Seoul 01811, Korea
Funding
This study was supported by the Research Program funded by the SeoulTech (Seoul National University of Science and Technology).
References (36)
Show source-provided references
1. Overview of control and grid synchronization for distributed power generation systems10.1109/TIE.2006.881997 ↗
2. Achieving a 100% renewable grid: Operating electric power systems with extremely high levels of variable renewable energy10.1109/MPE.2016.2637122 ↗
3. Design and control of an LCL-filter-based three-phase active rectifier10.1109/TIA.2005.853373 ↗
4. Direct realization of digital differentiators in discrete domain for active damping of LCL-type grid-connected inverter10.1109/TPEL.2017.2780174 ↗
5. Modeling and stability analysis of LCL-Type grid-connected inverters a comprehensive overview10.1109/ACCESS.2019.2935806 ↗
6. LCL filter design and performance analysis for grid-interconnected systems10.1109/TIA.2013.2274612 ↗
7. A review of passive power filters for three-phase grid-connected voltage-source converters10.1109/JESTPE.2015.2507203 ↗
8. Stability of photovoltaic and wind turbine grid-connected inverters for a large set of grid impedance values10.1109/TPEL.2005.861185 ↗
9. Control design guidelines for single-phase grid-connected photovoltaic inverters with damped resonant harmonic compensators10.1109/TIE.2009.2017820 ↗
10. Impedance shaping of the grid-connected inverter with LCL filter to improve its adaptability to the weak grid condition10.1109/TPEL.2014.2300235 ↗
11. Damping methods for resonances caused by LCL-filter-based current-controlled grid-tied power inverters: An overview10.1109/TIE.2017.2714143 ↗
12. Design and analysis of robust active damping for LCL filters using digital notch filters10.1109/TPEL.2016.2565598 ↗
13. Direct grid current control of LCL-filtered grid-connected inverter mitigating grid voltage disturbance10.1109/TPEL.2013.2264098 ↗
14. 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 ↗
15. Tran, T.V., Yoon, S.J., and Kim, K.H. (2018). An LQR-based controller design for an LCL-filtered grid-connected inverter in discrete-time state-space under distorted grid environment. Energies, 11.10.3390/en11082062 ↗
16. Bimarta, R., Tran, T.V., and Kim, K.H. (2018). Frequency-adaptive current controller design based on LQR state feedback control for a grid-connected inverter under distorted grid. Energies, 11.10.3390/en11102674 ↗
17. Full-state feedback equivalent controller for active damping in LCL-filtered grid-connected inverters using a reduced number of sensors10.1109/TIE.2015.2424391 ↗
18. Full feedforward of grid voltage for discrete state feedback controlled grid-connected inverter with LCL filter10.1109/TPEL.2012.2190524 ↗
19. Generalized closed-loop control schemes with embedded virtual impedances for voltage source converters with LC or LCL filters10.1109/TPEL.2011.2168427 ↗
20. Ruan, X., Wang, X., Pan, D., Yang, D., Li, W., and Bao, C. (2015). Control Techniques for LCL-Type Grid-Connected Inverters, Science Press. [1st ed.].
21. Variable structure control for three-phase LCL-filtered inverters using a reduced converter model10.1109/TIE.2017.2716881 ↗
22. Model predictive control for power converters in a distorted three-phase power supply10.1109/TIE.2016.2527732 ↗
23. Mitigation of DC and harmonic currents generated by voltage measurement errors and grid voltage distortions in transformerless grid-connected inverters10.1109/TEC.2017.2763240 ↗
24. Optimized design of multiresonant AC current regulators for single-phase grid-connected photovoltaic inverters10.1109/JPHOTOV.2019.2937386 ↗
25. Regions of active damping control for LCL filters10.1109/TIA.2013.2266892 ↗
26. Evaluations of current control in weak grid case for grid-connected LCL-filtered inverter10.1049/iet-pel.2012.0192 ↗
27. Li, M., Zhang, X., and Zhao, W. (2018). A novel stability improvement strategy for a multi-inverter system in a weak grid utilizing dual-mode control. Energies, 11.10.3390/en11082144 ↗
28. Wang, J., Yao, J., Hu, H., Xing, Y., He, X., and Sun, K. (2016, January 20–24). Impedance-based stability analysis of single-phase inverter connected to weak grid with voltage feed-forward control. Proceedings of the IEEE Applied Power Electronics Conference and Exposition (APEC), Long Beach, CA, USA.10.1109/APEC.2016.7468169 ↗
29. Generalized multifrequency current controller for grid-connected converters with LCL filter10.1109/TIA.2018.2829459 ↗
30. Kalmbach, O., Dirscherl, C., and Hackl, C.M. (2020). Discrete-time DC-link voltage and current control of a grid-connected inverter with LCL-filter and very small DC-link capacitance. Energies, 13.10.3390/en13215613 ↗
31. Dirscherl, C., Fessler, J., Hackl, C.M., and Ipach, H. (2015, January 21–23). State-feedback controller and observer design for grid-connected voltage source power converters with LCL-filter. Proceedings of the 2015 IEEE Multi-Conference on Systems and Control (CCA), Sydney, Australia.10.1109/CCA.2015.7320635 ↗
32. A systematic controller design for a grid-connected inverter with LCL filter using a discrete-time integral state feedback control and state observer10.3390/en11020437 ↗
33. Minimal invasive equivalent grid impedance estimation in inductive–resistive power networks using extended Kalman filter10.1109/TPEL.2013.2259507 ↗
34. Tarraso, A., Lai, N.B., Baltas, G.N., and Rodriguez, P. (2019). Power quality services provided by virtually synchronous FACTS. Energies, 12.10.3390/en12173292 ↗
35. Texas Instrument (2008). TMS320F28335 Digital Signal Controller (DSC)—Data Manual, Texas Instrument.
36. IEEE Standards Board (2003). IEEE Standard for Interconnecting Distributed Resources with Electric Power Systems, IEEE Standard.