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SoC balancing method for energy storage systems in DC microgrids using simplified droop control

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Abstract

DC microgrids adopt energy storage units to maintain the dynamic power balance between distributed power systems and the load. For DC microgrids in small-scale applications including residential microgrids, to ensure the coordination of the state of charge (SoC) and load current sharing among each of the energy storage units, an improved SoC-balanced control method without interconnection communication is proposed in this paper. The proposed method applies an adaptive droop control expression with a specific SoC-function to regulate its reference voltage in both the charging and discharging processes of the energy storage units. Thus, the balance of the SoC and the load current is achieved autonomously. This method can reduce the bus voltage deviation and weaken the impact of the output current on the bus voltage variation, especially for low-voltage DC microgrids. Moreover, the sampling of the output current is avoided, and both the cost and complexity of controller design are significantly reduced. In addition, a function curves analysis method is proposed to analyze the speed of the SoC balancing and the DC bus voltage deviation, which gives instruction in the choice of the adjustment factor in the adaptive droop equation. A mathematical description of the operating process and a small signal model of the proposed method are established to evaluate the system feasibility and stability. A laboratory-scale DC microgrid is built to verify the proposed method. Finally, simulation and experimental results are presented.

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References

  1. Dragičević, T., Lu, X., Vasquez, J.C., Guerrero, J.M.: DC microgrids-part I: a review of control strategies and stabilization techniques. IEEE Trans. Power Electron. 31(7), 4876–4891 (2016)

    Google Scholar 

  2. Hoang, T.V., Lee, H.H.: Distributed control scheme for accurate reactive power sharing with enhanced voltage quality for islanded microgrids. J. Power Electron. 20(2), 601–613 (2020)

    Article  Google Scholar 

  3. Jafari, M., Malekjamshidi, Z., Zhu, J., Khooban, M.: A novel predictive fuzzy logic-based energy management system for grid-connected and off-grid operation of residential smart microgrids. IEEE J. Emerg. Selected Topics Power Electron 8(2), 1391–1404 (2020)

    Article  Google Scholar 

  4. Meng, L., Shafiee, Q., Trecate, G.F., Karimi, H., Fulwani, D., Lu, X., Guerrero, J.M.: Review on control of DC microgrids and multiple microgrid clusters. IEEE J. Emerg. Selected Topics Power Electron. 5(3), 928–948 (2017)

    Google Scholar 

  5. Mokhtar, M., Marei, M.I., El-Sattar, A.A.: An adaptive droop control scheme for DC microgrids integrating sliding mode voltage and current controlled boost converters. IEEE Trans. Smart Grid. 10(2), 1685–1693 (2019)

    Article  Google Scholar 

  6. Nguyen, D.-L., Lee, H.-H.: Cooperative control strategy for voltage restoration and power allocation in DC microgrids. J. Power Electron. 20(4), 1025–1036 (2020)

    Article  Google Scholar 

  7. Shafiee, Q., Dragičević, T., Vasquez, J.C., Guerrero, J.M.: Hierarchical control for Multiple DC-microgrids clusters. IEEE Trans. Energy Convers. 29(4), 922–933 (2014)

    Article  Google Scholar 

  8. Moayedi, S., Davoudi, A.: Distributed tertiary control of DC microgrid clusters. IEEE Trans. Power Electron. 31(2), 1717–1733 (2016)

    Article  Google Scholar 

  9. Liu, S., Zheng, J., Li, Z., Liu, X.: A general piecewise droop design method for DC microgrid. Int. J. Electron. 1–19 (2020)

  10. Augustine, S., Mishra, M.K., Lakshminarasamma, N.: Adaptive droop control strategy for load sharing and circulating current minimization in low-voltage standalone DC microgrid. IEEE Trans. Sustain. Energy. 6(1), 132–141 (2015)

    Article  Google Scholar 

  11. Liu, S., Liu, R., Zheng, J., Liu, X.: Predictive function control in tertiary level for power flow management of DC microgrid clusters. Electron. Lett. 56(13), 675–676 (2020)

    Article  Google Scholar 

  12. Chen, X., Shi, M., Sun, H., Li, Y., He, H.: Distributed cooperative control and stability analysis of multiple DC electric springs in a DC microgrid. IEEE Trans. Industr. Electron. 65(7), 5611–5622 (2018)

    Article  Google Scholar 

  13. Hoang, K.D., Lee, H.: Accurate power sharing with balanced battery state of charge in distributed DC microgrid. IEEE Trans. Industr. Electron. 66(3), 1883–1893 (2019)

    Article  Google Scholar 

  14. Lu, X., Sun, K., Guerrero, J.M., Vasquez, J.C., Huang, L.: State-of-charge balance using adaptive droop control for distributed energy storage systems in DC microgrid applications. IEEE Trans. Industr. Electron. 61(6), 2804–2815 (2014)

    Article  Google Scholar 

  15. Lu, X., Sun, K., Guerrero, J.M., Vasquez, J.C., Huang, L.: Double-quadrant state-of-charge-based droop control method for distributed energy storage systems in autonomous DC microgrids. IEEE Trans. Smart Grid. 6(1), 147–157 (2015)

    Article  Google Scholar 

  16. Chendan, L., Dragicevic, T., Diaz, N.L., Vasquez, J.C., Guerrero, J.M.: Voltage scheduling droop control for State-of-Charge balance of distributed energy storage in DC microgrids. 2014 IEEE International Energy Conference (ENERGYCON). 1310–1314 (2014)

  17. Rui, H., Weaver, W.W.: Dc microgrid droop control based on battery state of charge balancing. 2016 IEEE Power and Energy Conference at Illinois (PECI). 1–8 (2016)

  18. Eydi, M., Ghazi, R.: Control strategy to improve load/power sharing, DC bus voltage restoration, and batteries SOC balancing in a DC microgrid. IET Renew. Power Gener. 14(14), 2668–2679 (2020)

    Article  Google Scholar 

  19. Zhi, N., Ding, K., Du, L., Zhang, H.: An SOC-based virtual DC machine control for distributed storage systems in DC microgrids. IEEE Trans. Energy Convers. 35(3), 1411–1420 (2020)

    Article  Google Scholar 

  20. Morstyn, T., Savkin, A.V., Hredzak, B., Agelidis, V.G.: Multi-agent sliding mode control for state of charge balancing between battery energy storage systems distributed in a DC microgrid. IEEE Trans. Smart Grid. 9(5), 4735–4743 (2018)

    Article  Google Scholar 

  21. Han, R., Tucci, M., Martinelli, A., Guerrero, J.M., Ferrari, G.: Stability analysis of primary plug-and-play and secondary leader-based controllers for DC microgrid clusters. IEEE Trans. Power Syst. 34(3), 1780–1800 (2019)

    Article  Google Scholar 

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Acknowledgements

This work was supported in part by the Anhui Provincial Natural Science Foundation, China (1708085ME106, KJ2017A067). Besides, the authors wish to thank the Key Lab of Power Electronics & Motion Control Anhui University of Technology for their support.

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Authors and Affiliations

  1. School of Electrical and Information Engineering, Anhui University of Technology, Ma’anshan, China

    Nan Qi, Wei Fang, Wei Wang, Xiaodong Liu & Sucheng Liu

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  1. Nan Qi
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  2. Wei Fang
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  3. Wei Wang
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  4. Xiaodong Liu
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  5. Sucheng Liu
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Correspondence to Wei Fang.

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Qi, N., Fang, W., Wang, W. et al. SoC balancing method for energy storage systems in DC microgrids using simplified droop control. J. Power Electron. 21, 1200–1212 (2021). https://doi.org/10.1007/s43236-021-00260-6

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  • DOI: https://doi.org/10.1007/s43236-021-00260-6

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