Journal of Electrical Engineering and Technology

The Korean Institute of Electrical Engineers (대한전기학회)
권호 표지
DOI QR코드

DOI QR Code

Sensorless Active Damping Method for an LCL Filter in Grid-Connected Parallel Inverters for Battery Energy Storage Systems

  • Sung, Won-Yong (Department of Electrical and Computer Engineering, Sungkyunkwan University) ;
  • Ahn, Hyo Min (Department of Electrical and Computer Engineering, Sungkyunkwan University) ;
  • Ahn, Jung-Hoon (Department of Electrical and Computer Engineering, Sungkyunkwan University) ;
  • Lee, Byoung Kuk (Department of Electrical and Computer Engineering, Sungkyunkwan University)
  • Received : 2017.09.18
  • Accepted : 2017.10.20
  • Published : 2018.01.01
Download PDF
⟨ Previous Next ⟩

Abstract

A sensorless active damping scheme for LCL filters in grid-connected parallel inverters for battery energy storage systems is proposed. This damping method is superior to the conventional notch filter and virtual damping methods with respect to robustness against the variation of the resonance of the filter and unnecessary additional current sensors. The theoretical analysis of the proposed damping method is explained in detail, along with the characteristic comparison to the conventional active damping methods. The performance verification of the proposed sensorless active damping method shows that its performance is comparable to that of the conventional virtual damping method, even without additional current sensors. Finally, simulation and experimental results are provided to examine the overall characteristics of the proposed method.

Keywords

E1EEFQ_2018_v13n1_280_f0001.png 이미지

Fig. 1. Configuration of parallel connected inverters withLCL-filters

E1EEFQ_2018_v13n1_280_f0002.png 이미지

Fig. 2. Circuit diagram of a single grid-connected inverter

E1EEFQ_2018_v13n1_280_f0003.png 이미지

Fig. 3. Thevenin equivalent model of a single grid-connected inverter

E1EEFQ_2018_v13n1_280_f0004.png 이미지

Fig. 4. Thevenin equivalent model of parallel-connectedinverters with LCL-filters

E1EEFQ_2018_v13n1_280_f0005.png 이미지

Fig. 5. Variation of admittance of conventional parallel connected inverters

E1EEFQ_2018_v13n1_280_f0006.png 이미지

Fig. 6. Block diagram of the conventional notch filter active damping method

E1EEFQ_2018_v13n1_280_f0007.png 이미지

Fig. 7. Block diagram of conventional virtual resistor active damping

E1EEFQ_2018_v13n1_280_f0008.png 이미지

Fig. 8. Block diagram of proposed sensorless damping method

E1EEFQ_2018_v13n1_280_f0009.png 이미지

Fig. 9. Admittance of parallel connected inverters withnotch filter method

E1EEFQ_2018_v13n1_280_f0010.png 이미지

Fig. 10. Admittance of parallel connected inverters withproposed sensorless active damping method

E1EEFQ_2018_v13n1_280_f0011.png 이미지

Fig. 11. Estimated capacitor current and actual capacitor current

E1EEFQ_2018_v13n1_280_f0012.png 이미지

Fig. 12. Simulation waveforms of 8-parallel-connectedinverter with conventional notch filter method

E1EEFQ_2018_v13n1_280_f0013.png 이미지

Fig. 13. Simulation waveforms of 8-parallel-connectedinverter with conventional virtual resistor method

E1EEFQ_2018_v13n1_280_f0014.png 이미지

Fig. 14. Simulation waveforms of 8-parallel-connectedinverter with proposed active damping method

E1EEFQ_2018_v13n1_280_f0015.png 이미지

Fig. 15. Experimental results of the 3-parallel connectedinverter with proposed active damping method

Table 1. System parameters of inverter system

E1EEFQ_2018_v13n1_280_t0001.png 이미지

References

  1. H. M. Ahn, C. Y. Oh, W. Y. Sung, J. H. Ahn, and B. K. Lee, "Analysis and design of LCL filter with passive damping circuits for three-phase gridconnected inverters," ICPE 2015-ECCE Asia, Seoul, South Korea, pp. 652-658, 1-5 June 2015.
  2. W. Wu, Y. He and T. Tang, "A New Design Method for the Passive Damped LCL and LLCL Filter-Based Single-Phase Grid-Tied Inverter," IEEE Trans. Ind. Electron., vol. 60, no. 10, pp. 4339-4350, Oct. 2013. https://doi.org/10.1109/TIE.2012.2217725
  3. H. M. Ahn, C. Y. Oh, W. Y. Sung, J. H. Ahn, and B.K. Lee, "Analysis and design of LCL filter with passive damping circuits for three-phase grid-connected inverters," J. Elect. Eng. Tech., vol. 12, no. 1, pp. 217-224, Jan. 2017. https://doi.org/10.5370/JEET.2017.12.1.217
  4. Z. Wenqiang and C. Guozhu, "Comparison of Active and Passive Damping Methods for Application in High Power Active Power Filter with LCL-filter," in Sustainable Power Generation and Supply, 2009. SUPERGEN '09. International Conference on, pp. 1- 6, 2009.
  5. L. Poh Chiang and D. G. Holmes, "Analysis of Multiloop Control Strategies for LC/CL/LCL-Filtered Voltage-Source and Current-Source Inverters," Industry Applications, IEEE Transactions on, vol. 41, pp. 644- 654, 2005. https://doi.org/10.1109/TIA.2005.844860
  6. K. Jalili and S. Bernet, "Design of LCL Filters of Active-Front-End Two-Level Voltage-Source Converters," Industrial Electronics, IEEE Transactions on, vol. 56, pp. 1674-1689, 2009.
  7. K. H. Ahmed, S. J. Finney, and B. W. Williams, "Passive Filter Design for Three-Phase Inverter Interfacing in Distributed Generation," in Compatibility in Power Electronics, 2007. CPE '07, 2007, pp. 1-9.
  8. A. A. Rockhill, M. Liserre, R. Teodorescu, and P. Rodriguez, "Grid-Filter Design for a Multimegawatt Medium-Voltage Voltage-Source Inverter," Industrial Electronics, IEEE Transactions on, vol. 58, pp. 1205- 1217, 2011.
  9. C. Byung-Geuk and S. Seung-Ki, "LCL Filter Design for Grid-Connected Voltage Source Converters in High Power Systems," in Energy Conversion Congress and Exposition (ECCE), 2012 IEEE, 2012, pp. 1548-1555.
  10. H. Jinwei, Y. W. Li, D. Bosnjak, and B. Harris, "Investigation and Active Damping of Multiple Resonances in a Parallel-Inverter-Based Microgrid," IEEE Trans. Power Electron., vol. 28, no. 1, pp. 234- 246, Jan. 2013. https://doi.org/10.1109/TPEL.2012.2195032
  11. J. He and Y. W. Li, "Generalized Closed-Loop Control Schemes with Embedded Virtual Impedances for Voltage Source Converters with LC or LCL Filters," IEEE Trans. Power Electron., vol. 27, no. 4, pp. 1850-1861, Apr. 2012. https://doi.org/10.1109/TPEL.2011.2168427
  12. J. M. Guerrero, L. GarciadeVicuna, J. Matas, M. Castilla, and J. Miret, "Output Impedance Design of Parallel-Connected UPS Inverters with Wireless Load-Sharing Control," IEEE Trans. Ind. Electron., vol. 52, no. 4, pp. 1126-1135, Aug. 2005. https://doi.org/10.1109/TIE.2005.851634
  13. Zhiyong Chen, An Luo, Yandong Chen, Mingshen Li, "Resonance Features of Multi-Paralleled Grid- Connected Inverters and Its Damping Method", Electronics and Application Conference and Exposition (PEAC), 2014 International, 5-8, pp. 120-125, Nov. 2014.
  14. R. Juntunen, J. Korhonen, T. Musikka, L. Smirnova, O. Pyrhonen, and P. Silventoinen, "Identification of Resonances in Parallel Connected Grid Inverters with LC- and LCL-Filters," in Proc. IEEE Appl. Power Electron. Conf. Expo., 2015, pp. 2122-2127.