Karafan Journal

Karafan Journal

Improving Reactive Power Sharing in Islanded Microgrid with Transient Reactive Current Injection

Document Type : Original Article

Author
Assistant Professor, Department of Electrical Engineering, Technical and Vocational University (TVU), Tehran, Iran.
Abstract
Accurate load power sharing and voltage regulation are two critical control objectives to ensure power quality and reliable operation of islanded microgrids. Although voltage regulation can be achieved using a secondary control loop, the inaccuracy of reactive power sharing is a prominent issue due to the varying impedance of lines connected to distributed generation sources. One of the techniques for accurate sharing of reactive power is to modify the production reference voltage by the droop control method. In this paper, a control strategy is proposed to improve the accuracy of reactive power sharing among distributed generation units of islanded microgrids. The proposed control method was based on transient reactive current injection to modify the production reference voltage of the droop control method. The reactive power-sharing error was reduced by changing the reference voltage. In addition, the proposed controller did not require a communication link between distributed generation sources for implementation. The effect of the proposed controller on the stability of the system was demonstrated using the reduced-order small-signal model. To evaluate the performance and effectiveness of the proposed control strategy, it was implemented on an islanded microgrid consisting of three distributed generation units. The simulation results showed the proper performance and efficiency of the proposed method.
Keywords
Subjects

[1] Ahmadi, S. E., & Rezaei, N. (2020). A new isolated renewable based multi microgrid optimal energy management system considering uncertainty and demand response. International Journal of Electrical Power & Energy Systems, 118, 105760. https://doi.org/10.101 6/j.ijepes.2019.105760
[2] Bouzid, A. E. M., Sicard, P., Chaoui, H., Cheriti, A., Sechilariu, M., & Guerrero, J. M. (2019). A novel Decoupled Trigonometric Saturated droop controller for power sharing in islanded low-voltage microgrids. Electric Power Systems Research, 168, 146-161. https://doi.org/10.1016/j.epsr.2018.11.016
[3] Mohammed, N., Callegaro, L., Ciobotaru, M., & Guerrero, J. M. (2023). Accurate power sharing for islanded DC microgrids considering mismatched feeder resistances. Applied Energy, 340, 121060. https://doi.org/10.1016/j.apenergy.2023.121060
[4] Pan, H., Teng, Q., & Wu, D. (2020). MESO-based robustness voltage sliding mode control for AC islanded microgrid. Chinese Journal of Electrical Engineering, 6(2), 83-93. https://doi.org/10.23919/CJEE.2020.000013
[5] Sabzevari, K., Karimi, S., Khosravi, F., & Abdi, H. (2019). A novel partial transient active-reactive power coupling method for reactive power sharing. International Journal of Electrical Power & Energy Systems, 113(4), 758-771. https://doi.org/10.1016/j.ij epes.2019.06.028
[6] Dragičević, T., Lu, X., Vasquez, J. C., & Guerrero, J. M. (2016). DC Microgrids—Part I: A Review of Control Strategies and Stabilization Techniques. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 31(7), 4876-4891. h ttps://doi.org/10.1109/TPEL.2015.2478859
[7] Wang, H., & Wang, X. (2023). Distributed reactive power control strategy based on adaptive virtual reactance. The Institution of Engineering and Technology Renewable Power Generation, 17(3), 762-773. https://doi.org/10.1049/rpg2.12632
[8] Mahmood, H., Michaelson, D., & Jiang, J. (2015). Accurate Reactive Power Sharing in an Islanded Microgrid Using Adaptive Virtual Impedances. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 30(3), 1605-1617. https:/ /doi.org/10.1109/TPEL.2014.2314721
[9] Sabzevari, K., Karimi, S., Khosravi, F., & Abdi, H. (2019). Modified droop control for improving adaptive virtual impedance strategy for parallel distributed generation units in islanded microgrids. International Transactions on Electrical Energy Systems, 29(1), e2689. https://doi.org/10.1002/etep.2689
[10] Truong, D-N., Pham, X. H. T., Doan, N. X., & Tran, H. V. (2023). Power control in microgrid using improved virtual impedance method. The Journal of Engineering, 2023(5), e12274. https://doi.org/10.1049/tje2.12274
[11] Vijay, A. S., Parth, N., Doolla, S., & Chandorkar, M. C. (2021). An Adaptive Virtual Impedance Control for Improving Power Sharing Among Inverters in Islanded AC Microgrids. Institute of Electrical and Electronics Engineers Transactions on Smart Grid, 12(4), 2991-3003. https://doi.org/10.1109/TSG.2021.3062391
[12] Yao, W., Chen, M., Matas, J., Guerrero, J. M., & Qian, Z. M. (2011). Design and Analysis of the Droop Control Method for Parallel Inverters Considering the Impact of the Complex Impedance on the Power Sharing. Institute of Electrical and Electronics Engineers Transactions on Industrial Electronics, 58(2), 576-588. https://doi.org/1 0.1109/TIE.2010.2046001
[13] Zhang, M., Du, Z., Lin, X., & Chen, J. (2015). Control Strategy Design and Parameter Selection for Suppressing Circulating Current Among SSTs in Parallel. Institute of Electrical and Electronics Engineers Transactions on Smart Grid, 6(4), 1602-1609. https://doi.org/10.1109/TSG.2015.2402835
[14] Li, Y. W., & Kao, C. N. (2009). An Accurate Power Control Strategy for Power-Electronics-Interfaced Distributed Generation Units Operating in a Low-Voltage Multibus Microgrid. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 24(12), 2977-2988. https://doi.org/10.1109/TPEL.2009.2022828
[15] Zhang, Y., & Ma, H. (2012). Theoretical and Experimental Investigation of Networked Control for Parallel Operation of Inverters. Institute of Electrical and Electronics Engineers Transactions on Industrial Electronics, 59(4), 1961-1970. https://doi.org /10.1109/TIE.2011.2165459
[16] Yajuan, G., Vasquez, J. C., & Guerrero, J. M. (2014, may 13-16). A simple autonomous current-sharing control strategy for fast dynamic response of parallel inverters in islanded microgrids. 2014 Institute of Electrical and Electronics Engineers International Energy Conference, Cavtat, Croatia. https://doi.org/10.1109/ENERGYCON.2014.6 850426
[17] Cho, B. G., & Sul, S. K. (2013, June 3-6). Power sharing strategy in parallel operation of inverters for distributed power system under line impedance inequality. 2013 Institute of Electrical and Electronics Engineers Energy Conversion Congress and Exhibition Asia Downunder, Melbourne, Victoria., Australia. https://doi.org/10.1109/ECCE-A sia.2013.6579121
[18] Golestan, S., Mousazadeh, S. Y., Guerrero, J. M., & Vasquez, J. C. (2017). A Critical Examination of Frequency-Fixed Second-Order Generalized Integrator-Based Phase-Locked Loops. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 32(9), 6666-6672. https://doi.org/10.1109/TPEL.2017.2674973
[19] Kim, J-H., Lee, Y-S., Kim, H-J., & Han, B-M. (2017). A New Reactive-Power Sharing Scheme for Two Inverter-Based Distributed Generations with Unequal Line Impedances in Islanded Microgrids. Energies, 10(11), 1800. https://doi.org/10.3390/en10111800
[20] Nazib, A. A., Holmes, D. G., & McGrath, B. P. (2018, May 20-24). Decoupled DSOGI-PLL for Improved Three Phase Grid Synchronisation. 2018 International Power Electronics Conference, Niigata, Japan. https://doi.org/10.23919/IPEC.2018.8507364
[21] Sao, C. K., & Lehn, P. W. (2008). Control and Power Management of Converter Fed Microgrids. Institute of Electrical and Electronics Engineers Transactions on Power Systems, 23(3), 1088-1098. https://doi.org/10.1109/TPWRS.2008.922232
[22] Xiao, F., Dong, L., Li, L., & Liao, X. (2017). A Frequency-Fixed SOGI-Based PLL for Single-Phase Grid-Connected Converters. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 32(3), 1713-1719. https://doi.org/10. 1109/TPEL.2016.2606623
[23] Lee, C. T., Chu, C. C., & Cheng, P. T. (2013). A New Droop Control Method for the Autonomous Operation of Distributed Energy Resource Interface Converters. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 28(4), 1980-1993. https://doi.org/10.1109/TPEL.2012.2205944
[24] Shafiee, Q., Guerrero, J. M., & Vasquez, J. C. (2014). Distributed Secondary Control for Islanded Microgrids—A Novel Approach. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 29(2), 1018-1031. https://doi.org/10.1109/TPE L.2013.2259506
[25] He, J., & Li, Y. W. (2012). An Enhanced Microgrid Load Demand Sharing Strategy. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 27(9), 3984-3995. https://doi.org/10.1109/TPEL.2012.2190099
[26] Ramezani, M., Li, S., & Sun, Y. (2017). Combining droop and direct current vector control for control of parallel inverters in microgrid. The Institution of Engineering and Technology Renewable Power Generation, 11(1), 107-114. https://doi.org/10.1049/iet-rpg.2016 .0107
Volume 20, Issue 3 - Serial Number 64
Engineering
Autumn 2023
Pages 393-417

  • Receive Date 30 April 2023
  • Revise Date 04 October 2023
  • Accept Date 14 November 2023