Abstract：Virtualsynchronous generator(VSG) can make distributed generation connect to power grid friendly. However,in actual operation, there are some low-order harmonics in grid voltage, which will generate the same order harmonics in grid-connected current and worsen the power quality. As for the problem, current harmonics are suppressed by remodeling the admittance at the harmonic frequencies in this paper. Firstly, admittance model of VSG is established. Then the reason that grid voltage harmonics can affect grid-connected current is analyzed. Secondly, according to admittance model, a grid voltage feedforward strategy is proposed based on notch filter, which can suppress current harmonics by remodeling the admittance at the harmonic frequencies. the transfer function of the grid voltage feedforward is obtained. A feedforward partly strategy at the harmonic frequencies is adopted in order to solve the problem that the transfer function of grid voltage feedforward contains differential terms and has a high gain in the base frequency which will cause over modulation. Finally simulation results and experimental results verify the correctness and effectiveness of the proposed strategy.
耿乙文, 田芳芳, 孙帅, 魏晨曦, 张洋. 一种基于虚拟同步发电机的电流谐波抑制方法[J]. 电工技术学报, 2018, 33(5): 1040-1050.
GengYiwen, TianFangfang, SunShuai, Wei Chenxi, Zhang Yang. A Method of Current Harmonics Suppression Based on VSG. Transactions of China Electrotechnical Society, 2018, 33(5): 1040-1050.
[1] Solangi K H, Islam M R, Saidur R, et al.A review on global solar energy policy[J].Renewable and Sustainable Energy Reviews, 2011, 15(4): 2149-2163. [2] TanWS,HassanMY, Majid M S, et al. Optimal distributed renewable generation planning: a review of different approaches[J]. Renewable and Sustainable Energy Reviews, 2013, 18: 626-645. [3] 范明天, 张祖平, 苏傲雪, 等. 主动配电系统可行技术的研究[J].中国电机工程学报, 2013, 33(22): 12-18. Fan Mingtian, Zhang Zuping, Su Aoxue, et al.Enablingtechnologiesfor active distributionsystems[J]. Proceedings of the CSEE, 2013, 33(22): 12-18. [4] Borges C L T, Martins V F. Multistage expansion planning for active distribution networks under demand and distributed generation uncertainties[J]. Electrical Power and Energy Systems, 2012, 36(1): 107-116. [5] 梁才浩, 段献忠. 分布式发电及其对电力系统的影响[J].电力系统自动化, 2001, 25(6): 53-56. Liang Caihao, Duan Xianzhong.Distributed generation and its impact on power system[J]. Automation of Electric Power Systems, 2001, 25(6): 53-56. [6] 张谦, 廖清芬, 唐飞, 等. 计及分布式电源接入的配电网静态电压稳定性评估方法[J]. 电力系统自动化, 2015, 39(15): 42-48. Zhang Qian, Liao Qingfen, Tang Fei, et al.Steady statevoltage stability assessment method of distributionnetwork considering inter-connetction of distributedgenerators[J]. Automation of Electric Power Systems,2015,39(15):42-48. [7] Beck H P, Hesse R.Virtual synchronous machine[C]//9th International Conference on Electrical Power Quality and Utilisation, Barcelona, Spain, 2007: 1-6. [8] 丁明, 杨向真, 苏建徽. 基于虚拟同步发电机思想的微电网逆变电源控制策略[J]. 电力系统自动化, 2009, 33(8): 89-93. Ding Ming, Yang Xiangzhen, Su Jianhui.Control strategies of inverters based on virtual synchronous generator in a microgrid[J]. Automation of Electric Power Systems, 2009, 33(8): 89-93. [9] Chen Yong, Hesse R, Turschner D, et al.Investigation of the virtual synchronous machine in the island mode[C]//3rd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies, Berlin, Germany, 2012: 1-6. [10] Beck H P, Hesse R.Virtual synchronous machine[C]//2007 9th International Conference on Electrical Power Quality and Utilisation, Barcelona, Spain, 2007: 1-6. [11] Gao Fang, Iravatii M R.A control strategy for a distributed generation unit in grid-connected and autonomous modes of operation[J]. IEEE Transactions on Power Delivery, 2008, 23(2): 850-859. [12] Chen Yong, Hesse R, Turschner D, et al.Improving the grid powerquality using virtual synchronous machines[C]//International Conference on Power Engineering, Energy and Electrical Drives, Malaga, Spain, 2011: 1-6. [13] Zhong Qingchang, Weiss G.Synchronverters: inverters that mimic synchronous generators[J]. IEEE Transactions on Industrial Electronics, 2011, 58(4):1259-1267. [14] Zhong Qingchang, Nguyen P L, Ma Zhenyu, et al.Self-synchronized synchronverters: inverters without a dedicated synchronization unit[J]. IEEE Transactions on Power Electronics, 2014, 29(2):617-630. [15] 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. LüZhipeng,Sheng Wanxing,ZhongQingchang,et al. Virtual synchronous generator and its applications in micro-grid[J].Proceedingsof the CSEE, 2014,34(16):2591-2603. [16] Alipoor J, Miura Y, Ise T.Power system stabilization using virtual synchronous generator with alternating moment of inertia[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2015, 3(2):451-458. [17] Sakimoto K, MiuraY, Ise T. Stabilization of a power system with a distributed generator by a virtual synchronous generator function[C]//2011 IEEE 8th International Conference on Power Electronics and ECCE Asia, Jeju, South Korea, 2011: 1498-1505. [18] Sakimoix K I, Sugimoto K, Shindo Y. Low voltageride through capability of a grid connected inverter based on the virtual synchronous generator[C]//2013 IEEE 10th International Conference on Power Electronics and Drive Systems(PEDS), Kitakyushu, Japan, 2013: 1066-1071. [19] Wang Shuo, Hu Jiabing, Yuan Xiaoming.Virtual synchronous control for grid-connected DFIG-based wind turbines[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2015, 3(4):932-944. [20] Zhao Yangyang, Chai Jianyun, Sun Xudong.Virtual synchronous control of grid-connected DFIG-based wind turbines[C]//2015 IEEE Applied Power Electronics Conference and Exposition (APEC), Charlotte, NC, USA, 2015:2980-2983. [21] IEEE Recommended Practice for Utility Interface of Photovoltaic (PV) Systems[S].IEEE Standard 929,2000. [22] IEEE Standard for Interconnecting Distributed Resources with Electric PowerSystems[S]. IEEE Standard 1547,2003. [23] Generating Plants Connected the Medium-Voltage Network. BDEW technicalguideline[S], 2008. [24] 分布式电源接入电网技术规定. 国家电网公司企业标准Q/GDW480[S]. 2010. [25] 光伏电站接入电网技术规定. 国家电网公司企业标准Q/GDW617[S]. 2011. [26] Jia Yaoqin, Zhao Jiqian, Fu Xiaowei.Direct grid current control of LCL-filtered grid-connected inverter mitigating grid voltage disturbance[J]. IEEE Transactions on Power Electronics, 2014, 29(3):1532-1541. [27] Khajehoddin S A, Karimi-Ghartemani M, Jain P, et al.A frequency adaptive resonant controller for fixed point digital implementation at high, sampling frequency[C]//2011 IEEEEnergy Conversion Congress and Exposition, Phoenix, AZ, USA, 2011: 2557-2561. [28] Liserre M, Teodorescu R, Blaabjerg F.Stability of photovoltaic and wind turbinegrid-connected inverters for a large set of grid impedance values[J]. IEEE Transactionson Power Electronics, 2006,21(1): 263-272. [29] 邱晓明, 王明渝, 胡文翠. LLCL滤波的单相光伏并网逆变器控制技术研究[J]. 电力系统保护与控制,2013,41(10): 74-79. Qiu Xiaoming,Wang Mingyu,Hu Wencui.LLCL filter based single-phase photovoltaic grid-connected inverter control strategy[J]. Power System Protection and Control, 2013,41(10):74-79. [30] Wang Xuehua, Ruan Xinbo, Liu Shangwei,et al.Full feedforward of grid voltage for grid-connected inverter with LCL filter to suppress current distortion due to grid voltage harmonics[J]. IEEE Transactions on Power Electronics, 2010, 25(12): 3119-3127. [31] Li Weiwei, Ruan Xinbo, Pan Donghua, et al.full-feedforward schemes of grid voltages for a three-phase-type grid-connected inverter[J]. IEEE Transactions on Industrial Electronics, 2013, 60(6): 2237-2250. [32] Mohamed Y A I. Suppression of low-and high-frequency instabilities and grid-induced disturbances in distributed generation inverters[J]. IEEE Transactions on Power Electronics, 2011, 26(12):3790-3803. [33] 吴云亚, 谢少军, 阚加荣, 等. 逆变器侧电流反馈的LCL并网逆变器电网电压前馈控制策略[J].中国电机工程学报,2013,33(6): 54-60. Wu Yunya,Xie Shaojun,Kan Jiarong,et al.A full grid voltage feed-forward control strategy with inverter-side current feedback for LCL grid-connected inverters[J]. Proceedings of the CSEE, 2013,33(6):54-60. [34] 王学华, 阮新波, 刘尚伟. 抑制电网背景谐波影响的并网逆变器控制策略[J]. 中国电机工程学报,2011,31(6): 7-14. Wang Xuehua,Ruan Xinbo,Liu Shangwei.Control strategy for grid-connected inverter to suppress current distortion effected by background harmonics in grid voltage[J]. Proceedings of the CSEE, 2011, 31(6):7-14. [35] 张玉治, 张辉, 贺大为, 等. 具有同步发电机特性的微电网逆变器控制[J]. 电工技术学报,2014,29(7): 261-268. Zhang Yuzhi,Zhang Hui,He Dawei,et al.Control strategy of micro grid converters with synchronous generator characteristic[J]. Transactions of China Electrotechnical Society, 2014,29(7): 261-268. [36] 吴轩钦, 谭国俊, 何凤有, 等. 变频驱动系统电网接口虚拟同步发电机控制技术[J]. 电工技术学报,2015,30(23): 83-92. WuXuanqin,Tan Guojun, He Fengyou, et al.Virtual synchronous generator control scheme of grid interface for variable frequency drive systems[J]. Transactions of China Electrotechnical Society, 2015, 30(23): 83-92.
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