This paper proposes an improved droop control strategy for DC microgrid based on superimposed frequency. First, the AC voltage is superimposed on the output voltage of the converter to construct the droop characteristics between the AC voltage frequency and the output current. At the same time, the reactive power generated by the AC voltage is used to adjust the output voltage of each DG converter to achieve accurate current distribution; Then, through the introduction of virtual resistance and voltage secondary compensation measures, the bus voltage is restored and the system stability is improved. This control strategy does not require a communication network, and effectively improves the plug-and-play performance of the microgrids. Finally, the feasibility and effectiveness of the control strategy are verified through simulation.
Xue Yang, Huang Xincao, Xi Dongxiang, Chen Yuefan, Ding Zilong.
RESEARCHON IMPROVED DROOP CONTROL STRATEGYOF DC MICROGRID BASED ON SUPERIMPOSED FREQUENCY[J]. Acta Energiae Solaris Sinica. 2022, 43(9): 461-467 https://doi.org/10.19912/j.0254-0096.tynxb.2021-0248
中图分类号:
TM721
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 杨新法, 苏剑, 吕志鹏, 等. 微电网技术综述[J]. 中国电机工程学报, 2014, 34(1): 57-70. YANG X F, SU J, LYU Z P, et al.Overview on micro-grid technology[J]. Proceedings of the CSEE, 2014, 34(1): 57-70. [2] 王成山, 李微, 王议锋, 等. 直流微电网母线电压波动分类及抑制方法综述[J]. 中国电机工程学报, 2017, 37(1): 84-98. WANG C S, LI W, WANG Y F, et al.DC bus voltage fluctuation classification and restraint methods review for DC microgrid[J]. Proceedings of the CSEE, 2017, 37(1): 84-98. [3] JIRDEHI M A, TABAR V S, GHASSEMZADEH S, et al.Different aspects of microgrid management: A comprehensive review[J]. The journal of energy storage, 2020, 30: 101457. [4] HOANG K D, LEE D C, LEE H H.Accurate current sharing and pcc voltage restoration in LVDC Microgrid without communication network[C]//2018 IEEE Energy Conversion Congress and Exposition(ECCE), IEEE, Portland, USA, 2018. [5] 米阳, 陈鑫, 季亮, 等. 基于虚拟额定电流的直流微电网分布式储能单元精确电流分配研究[J]. 电网技术, 2020, 44(3): 823-835. MI Y, CHEN X, JI L, et al.Accurate current sharing of distributed energy storage units in DC microgrid[J]. Power system technology, 2020, 44(3): 823-835. [6] 温春雪, 戴惟, 李建林, 等. 光储一体化并联系统优化控制设计分析[J]. 太阳能学报, 2021, 42(5): 150-159. WEN C X, DAI W, LI J L, et al.Design and analysis for optimal control of integrated with photovoltaic and energy storage parallel system[J]. Acta energiae solaris sinica, 2021, 42(5): 150-159. [7] DRAGICEVIC T, LU X, VASQUEZ J, et al.DC microgrids-Part I:a review of control strategies and stabilization techniques[J]. IEEE transactions on power electronics PE, 2016, 31(7): 4876-4891. [8] 蒋伟明, 赵晋斌, 高明明, 等. 具有电压自恢复特性的独立直流微电网控制策略研究[J]. 电网技术, 2020, 44(9): 3547-3555. JIANG W M, ZHAO J B, GAO M M, et al.Control strategy with voltage self-recovery characteristic for autonomous DC microgrid[J]. Power system technology, 2020, 44(9): 3547-3555. [9] 涂春鸣, 熊诵辉, 肖凡, 等. 基于电流跟踪的多直流微源并联运行主从控制策略[J]. 电网技术, 2017, 41(7): 2205-2215. TU C M, XIONG S H, XIAO F, et al.Master-slave control strategy for parallel operation of multiple DC micro-source based on current tracking[J]. Power system technology, 2017, 41(7): 2205-2215. [10] ANAND S, FERNANDES B G, GUERRERO J, et al.Distributed control to ensure proportional load sharing and improve voltage regulation in low-voltage DC microgrids[J]. IEEE transactions on power electronics, 2013, 28(4): 1900-1913. [11] 朱珊珊, 汪飞, 郭慧, 等. 直流微电网下垂控制技术研究综述[J]. 中国电机工程学报, 2018, 38(1): 72-84,344. ZHU S S, WANG F, GUO H, et al.Overview of droop control in DC microgrid[J]. Proceedings of the CSEE, 2018, 38(1): 72-84,344. [12] WANG P B, LU X N, YANG X, et al.An improved distributed secondary control method for DC microgrids with enhanced dynamic current sharing performance[J]. IEEE transactions on power electronics, 2016, 31(9): 6658-6673. [13] KHORSANDI A, ASHOURLOO M, MOKHTARI H, et al.Automatic droop control for a low voltage DC Microgrid[J]. IET generation transmission & distribution, 2016, 10(1): 41-47. [14] SILVAW W A G, OLIVEIRA T R, DONOSO-GARCIA P F. An improved voltage-shifting strategy to attain concomitant accurate power sharing and voltage restoration in droop-controlled DC microgrids[J]. IEEE transactions on power electronics, 2021, 36(2): 2396-2406. [15] XIAO N L, JOSEP M G, KAI S, et al.An improved droop control method for DC Microgrids based on low bandwidth communication with DC bus voltage restoration and enhanced current sharing accuracy[J]. IEEE transactions on power electronics, 2014, 29(4): 1800-1812. [16] 佟子昂, 武建文, 马速良, 等. 一种基于主动电压扰动的直流微网负载均流控制策略[J]. 电工技术学报, 2019, 34(24): 5199-5208. TONG Z A, WU J W, MA S L, et al.A load current-sharing control strategy for DC Microgrid converters based on active voltage disturbance[J]. Transactions of China Electrotechnical Society, 2019, 34(24): 5199-5208. [17] PEYGHAMI S, MOKHTARI H, LOH P C, et al.Distributed primary and secondary power sharing in a droop-controlled LVDC microgrid with merged AC and DC characteristics[J]. IEEE transactions on smart grid, 2018, 9(3): 2284-2294. [18] PEYGHAMI S, DAVARI P, MOKHTARI H, et al.Synchronverter-enabled DC power sharing approach for LVDC microgrids[J]. IEEE transactions on power electronics, 2016, 32(10): 8089-8099.