Transient Control Strategy of Droop-Controlled Inverter Considering Fault Current Limitation
Ge Pingjuan1, Xiao Fan1, Tu Chunming1, Chen Leqi1, Zhou Da2
1. National Electric Power Conversion and Control Engineering Technology Research CenterHunan University Changsha 410082 China; 2. State Grid Jiangsu Electric Power Co. Ltd Nanjing 210019 China
Abstract The droop-controlled inverter can provide voltage and frequency support for the power grid, and its transient stability is important. However, the stability of power angle and fault current affects the safe operation of the droop-controlled inverter under fault conditions. In this paper, the transient characteristics of the droop-controlled inverter are analyzed, and the influence of current limiter and Q-U loop on the transient characteristics of the inverter is described in detail. Accordingly, this paper proposes a transient control method for the droop-controlled inverter which takes into account both fault current limitation and power angle stability. The proposed method considers the variation of the grid voltage and the output voltage of the inverter during the fault period and realizes the power angle stability of the inverter by adjusting the active power reference. In addition, the fault current can be effectively suppressed by the optimal control of the Q-U control loop. Finally, the effectiveness of the proposed method is verified by simulation and experiment.
Ge Pingjuan,Xiao Fan,Tu Chunming等. Transient Control Strategy of Droop-Controlled Inverter Considering Fault Current Limitation[J]. Transactions of China Electrotechnical Society, 2022, 37(14): 3676-3687.
[1] 陈国平, 李明节, 许涛, 等. 关于新能源发展的技术瓶颈研究[J]. 中国电机工程学报, 2017, 37(1): 20-27. Chen Guoping, Li Mingjie, Xu Tao, et al.Study on technical bottleneck of new energy development[J]. Proceedings of the CSEE, 2017, 37(1): 20-27. [2] 钟庆昌, 霍尔尼克. 新能源接入智能电网的逆变控制关键技术[M]. 北京: 机械工业出版社, 2016. [3] 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. [4] 王成山, 王守相. 分布式发电供能系统若干问题研究[J]. 电力系统自动化, 2008, 32(20): 1-4. Wang Chengshan, Wang Shouxiang.Study on some key problems related to distributed generation systems[J]. Automation of Electric Power Systems, 2008, 32(20): 1-4. [5] 曾正, 赵荣祥, 汤胜清, 等. 可再生能源分散接入用先进并网逆变器研究综述[J]. 中国电机工程学报, 2013, 33(24): 1-12. Zeng Zheng, Zhao Rongxiang, Tang Shengqing, et al.An overview on advanced grid-connected inverters used for decentralized renewable energy resources[J]. Proceedings of the CSEE, 2013, 33(24): 1-12. [6] Rocabert J, Luna A, Blaabjerg F, et al.Control of power converters in AC microgrids[J]. IEEE Transa-ctions on Power Electronics, 2012, 27(11): 4734-4749. [7] Milano F, Dörfler F, Hug G, et al.Foundations and challenges of low-inertia systems[C]//Power Systems Computation Conference, Dublin, 2018, DOI: 10.23919/PSCC.2018.8450880. [8] Elkhatib M E, Du W, Lasseter R H.Evaluation of inverter-based grid frequency support using frequency-watt and grid-forming PV inverters[C]//IEEE Power & Energy Society General Meeting, Portland, 2018, DOI: 10.1109/PESGM.2018.8585958. [9] Markovic U, Stanojev O, Aristidou P, et al.Partial grid forming concept for 100% inverter-based trans-mission systems[C]//IEEE Power Energy Soc. General Meeting, Portland, 2018, DOI: 10.1109/PESGM.2018. 8586114. [10] 姜静雅, 王玮, 吴学智, 等. 基于自适应无功功率补偿的虚拟同步机功率解耦策略[J]. 电工技术学报, 2020, 35(13): 2747-2756. Jiang Jingya, Wang Wei, Wu Xuezhi, et al.Power decoupling strategy in virtual synchronous generator based on adaptive reactive power compensation[J]. Transactions of China Electrotechnical Society, 2020, 35(13): 2747-2756. [11] 王晓寰, 张旭东, 郭红强, 等. 基于相位簇扰动的下垂控制并网逆变器孤岛检测[J]. 电工技术学报, 2020, 35(8): 1728-1738. Wang Xiaohuan, Zhang Xudong, Guo Hongqiang, et al.Islanding detection of droop-controlled grid-connected inverters on phase cluster disturbance[J]. Transactions of China Electrotechnical Society, 2020, 35(8): 1728-1738. [12] Arani M F M, Mohamed Y A I. Analysis and impacts of implementing droop control in DFIG-based wind turbines on microgrid/weak-grid stability[J]. IEEE Trans on Power Systems, 2015, 30(1): 385-396. [13] Brabandere K D, Bolsens B, Keybus J V D, et al. A voltage and frequency droop control method for parallel inverters[J]. IEEE Transactions on Power Electronics, 2007, 22(4): 1107-1115. [14] 张健磊, 高湛军, 陈明, 等. 考虑复故障的有源配电网故障定位方法[J]. 电工技术学报, 2021, 36(11): 2265-2276. Zhang Jianlei, Gao Zhanjun, Chen Ming, et al.Fault location method for active distribution networks considering combination faults[J]. Transactions of China Electrotechnical Society, 2021, 36(11): 2265-2276. [15] 刘彦超. 含分布式电源配电网的快速故障区段定位[J]. 电气技术, 2017, 18(9): 61-65, 71. Liu Yanchao.Fast fault section locating for distri-bution network with distributed generations[J]. Electrical Engineering, 2017, 18(9): 61-65, 71. [16] Geng Hua, Liu Cong, Yang Geng.LVRT capability of DFIG-based WECS under asymmetrical grid fault condition[J]. IEEE Transactions on Industrial Elec-tronics, 2013, 60(6): 2495-2509. [17] Alam M R, Muttaqi K M, Bouzerdoum A.Characteri-zing voltage sags and swells using three-phase voltage ellipse parameters[J]. IEEE Transactions on Industry Applications, 2015, 51(4): 2780-2790. [18] 章雷其, 黄林彬, 黄伟, 等. 提高下垂控制逆变器虚拟功角暂态稳定性的控制方法[J]. 电力系统自动化, 2017, 41(12): 56-62, 99. Zhang Leiqi, Huang Linbin, Huang Wei, et al.Control methods for improving virtual power angle transient stability of droop-controlled inverters[J]. Automation of Electric Power Systems, 2017, 41(12): 56-62, 99. [19] D'Arco S, Suul J A. Equivalence of virtual syn-chronous machines and frequency-droops for converter-based microgrids[J]. IEEE Transactions on Smart Grid, 2014, 5(1): 394-395. [20] Simpson-Porco J W, Drfler F, Bullo F. Synchroni-zation and power sharing for droop-controlled inverters in islanded microgrids[J]. Automatica, 2012, 49(9): 2603-2611. [21] Rodriguez P, Timbus A V, Teodorescu R, et al.Flexible active power control of distributed power generation systems during grid faults[J]. IEEE Transactions on Industrial Electronics, 2007, 54(5): 2583-2592. [22] Wu Heng, Wang Xiongfei.Design-oriented transient stability analysis of grid-connected converters with power synchronization control[J]. IEEE Transactions on Industrial Electronics, 2019, 66(8): 6473-6482. [23] Pan Donghua, Wang Xiongfei, Liu Fangcheng, et al.Transient stability of voltage-source converters with grid-forming control: a design-oriented study[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2020, 8(2): 1019-1033. [24] Oureilidis K O, Demoulias C S.A fault clearing method in converter-dominated microgrids with conventional protection means[J]. IEEE Transactions on Power Electronics, 2016, 31(6): 4628-4640. [25] Paquette A D, Divan D M.Virtual impedance current limiting for inverters in microgrids with synchronous generators[J]. IEEE Transactions on Industry Appli-cations, 2014, 51(2): 1630-1638. [26] 黄林彬, 章雷其, 辛焕海, 等. 下垂控制逆变器的虚拟功角稳定机理分析[J]. 电力系统自动化, 2016, 40(12): 117-123, 150. Huang Linbin, Zhang Leiqi, Xin Huanhai, et al.Mechanism analysis of virtual power angle stability in droop-controlled inverters[J]. Automation of Electric Power Systems, 2016, 40(12): 117-123, 150. [27] Huang Linbin, Xin Huanhai, Wang Zhen, et al.Transient stability analysis and control design of droop-controlled voltage source converters con-sidering current limitation[J]. IEEE Transactions on Smart Grid, 2019, 10(1): 578-591.
2022, Vol. 37 
