Secondary Frequency Control Including Delay Compensation in Microgrids Based on Virtual Synchronous Generator
Chen Meng1, Xiao Xiangning1, Luo Chao2
1. State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources North China Electric Power University Beijing 102206 China; 2. Electric Power Research Institute, CSG Guangzhou 510663 China
Abstract Virtual synchronous generators can provide the virtual inertia for the power network to improve the frequency stability. However, the delays in communication lines will deteriorate the performance of the traditional secondary frequency control. The whole small-signal model including secondary frequency control and communication delay was built and used to investigate the impacts of the virtual synchronous generator on microgrid stability. The effects of the important control parameters such as virtual inertia on the delay margin were discussed. In terms of the negative effects of the communication delay, a corresponding delay compensation strategy for virtual synchronous generator was proposed to compensate the impacts of communication delay, where a predicting loop was added to the control. The comparisons of simulation results in PSCAD/EMTDC on dynamics with and without the communication delay compensation were carried out. It is shown that the proposed control strategy can effectively improve robustness of the microgrid frequency control on the communication delay, and enhance the frequency stability.
Chen Meng,Xiao Xiangning,Luo Chao. Secondary Frequency Control Including Delay Compensation in Microgrids Based on Virtual Synchronous Generator[J]. Transactions of China Electrotechnical Society, 2018, 33(16): 3845-3854.
[1] Rocabert J, Luna A, Blaabjerg F, et al.Control of power converters in AC microgrids[J]. IEEE Transactions on Power Electronics, 2012, 27(11): 4734-4749. [2] 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 Xinfa, Su Jian, Lü Zhipeng, et al.Overview on micro-grid technology[J]. Proceedings of the CSEE, 2014, 34(1): 57-70. [3] IEEE-PES Task Force on Microgrid Control. Trends in microgrid control[J]. IEEE Transactions on Smart Grid, 2014, 5(4): 1905-1919. [4] 肖湘宁. 新一代电网中多源多变换复杂交直流系统的基础问题[J]. 电工技术学报, 2015, 30(15): 1-14. Xiao Xiangning.Basic problems of the new complex AC-DC power grid with multiple energy resources and multiple conversions[J]. Transactions of China Electrotechnical Society, 2015, 30(15): 1-14. [5] 郑天文, 陈来军, 陈天一, 等. 虚拟同步发电机技术及展望[J]. 电力系统自动化, 2015, 39(21): 165-175. Zheng Tianwen, Chen Laijun, Chen Tianyi, et al.Review and prospect of virtual synchronous generator technologies[J]. Automation of Electric Power Systems, 2015, 39(21): 165-175. [6] Zhong Q C, Nguyen P L, Ma Z, et al.Self- synchronized synchronverters: Inverters without a dedicated synchronization unit[J]. IEEE Transactions on Power Electronics, 2014, 29(2): 617-630. [7] 吕志鹏, 盛万兴, 钟庆昌, 等. 虚拟同步发电机及其在微电网中的应用[J]. 中国电机工程学报, 2014, 34(16): 2591-2603. Lü Zhipeng, Sheng Wanxing, Zhong Qingchang, et al.Virtual synchronous generator and its applications in micro-grid[J]. Proceedings of the CSEE, 2014, 34(16): 2591-2603. [8] Frack P F, Mercado P E, Molina M G, et al.Control strategy for frequency control in autonomous micro- grids[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2015, 3(4): 1046-1055. [9] 石荣亮, 张兴, 刘芳, 等. 虚拟同步发电机及其在多能互补微电网中的运行控制策略[J]. 电工技术学报, 2016, 31(20): 170-180. Shi Rongliang, Zhang Xing, Liu Fang, et al.Control technologies of multi-energy complementary microgrid operation based on virtual synchronous generators[J]. Transactions of China Electrotechnical Society, 2016, 31(20): 170-180. [10] Guerrero J M, Vasquez J C, Matas J, et al.Hierarchical control of droop-controlled AC and DC microgrids-A general approach toward standardi- zation[J]. IEEE Transactions on Industrial Elec- tronics, 2011, 58(1): 158-172. [11] Zuo S, Davoudi A, Song Y, et al.Distributed finit- time voltage and frequency restoration in islanded AC microgrids[J]. IEEE Transactions on Industrial Electronics, 2016, 63(10): 5988-5997. [12] 鲍薇, 胡学浩, 李光辉, 等. 基于同步电压源的微电网分层控制策略设计[J]. 电力系统自动化, 2013, 37(23): 20-26. Bao Wei, Hu Xuehao, Li Guanghui, et al.Synchronous voltage source based design of hierarchical control strategy for microgrid[J]. Automation of Electric Power Systems, 2013, 37(23): 20-26. [13] 梁英, 盛万兴, 钟庆昌, 等. 基于同步逆变器的微电网二次调频策略及特性分析[J]. 中国电机工程学报, 2017, 37(2): 391-402. Liang Ying, Sheng Wanxing, Zhong Qingchang, et al.Secondary frequency regulation strategies and characteristics analysis of synchronverter-based microgrids[J]. Proceedings of the CSEE, 2017, 37(2): 391-402. [14] 张羽, 李咸善. 基于频率调整策略的微电网多目标优化自愈控制[J]. 电网技术, 2017, 41(3): 831-839. Zhang Yu, Li Xianshan.Multi-objective optimization for microgrid self-healing control based on frequency regulation strategy[J]. Power System Technology, 2017, 41(3): 831-839. [15] 李斌, 周林, 余希瑞, 等. 基于改进虚拟同步发电机算法的微网逆变器二次调频方案[J]. 电网技术, 2017, 41(8): 1-8. Li Bin, Zhou Lin, Yu Xirui, et al.Secondary frequency regulation for microgrid inverters based on improving virtual synchronous generator[J]. Power System Technology, 2017, 41(8): 1-8. [16] Bidram A, Davoudi A, Lewis F L, et al.Distributed cooperative secondary control of microgrids using feedback linearization[J]. IEEE Transactions on Power Systems, 2013, 28(3): 3463-3470. [17] Zhang C K, Jiang L, Wu Q H, et al.Delay-dependent robust load frequency control for time delay power systems[J]. IEEE Transactions on Power Systems, 2013, 28(3): 2192-2201. [18] Liu S, Wang X, Liu P X.Impact of communication delays on secondary frequency control in an islanded microgrid[J]. IEEE Transactions on Industrial Elec- tronics, 2015, 62(4): 2021-2031. [19] Ahumada C, Cárdenas R, Sáez D, et al.Secondary control strategies for frequency restoration in islanded microgrids with consideration of communication delays[J]. IEEE Transactions on Smart Grid, 2016, 7(3): 1430-1441. [20] 张波, 颜湘武, 黄毅斌, 等. 虚拟同步机多机并联稳定控制及其惯量匹配方法[J]. 电工技术学报, 2017, 32(10): 42-52. Zhang Bo, Yan Xiangwu, Huang Yibin, et al.Stability control and inertia matching method of multi-parallel virtual synchronous generators[J]. Transactions of China Electrotechnical Society, 2017, 32(10): 42-52. [21] D’Arco S, Suul J A, Fosso O B. Small-signal modelling and parametric sensitivity of a virtual synchronous machine in islanded operation[J]. Electrical Power Energy Systems, 2015, 72: 3-15. [22] 蒋文韬, 付立军, 王刚, 等. 直驱永磁风电机组虚拟惯量控制对系统小干扰稳定性影响分析[J]. 电力系统保护与控制, 2015, 43(11): 33-40. Jiang Wentao, Fu Lijun, Wang Gang, et al.Impact of direct-drive permanent magnet wind turbines virtual inertia control on power system small signal stability analysis[J]. Power System Protection and Control, 2015, 43(11): 33-40. [23] Jia H, Yu X.A simple method for power system stability analysis with multiple time delays[C]//IEEE Power and Energy Society General Meeting, Pittsburgh, PA, USA, 2008, DOI: 10.1109/PES.2008.4596157.
2018, Vol. 33 
