Abstract：This paper is focused on the analysis of the stability problems in a master-slave control based microgrid under islanded mode. The mathematic model of the considered microgrid based on discrete-time state equations is built firstly. Then through eigenvalues analysis, a pair of the high-frequency complex conjugate eigenvalues of the system characteristic matrix will move outside the unit cycle in the z plane with the variation of the proportion gain of the voltage loop of the master inverter. The number of slave converters and the local load parameters, which is shown by the PSCAD simulation results, where high-frequency oscillatory components occur in the AC bus voltage and the output currents of both the master and slave inverters. Consequently, band-pass filter based on a second-order generalized integrator(SOGI) is adopted for the feedback loop of the master converter voltage control, in order to improve the system stability and ensure the stable operation of the microgrid, which eventually verified on the master-slave microgrid built in the PSCAD simulation software.
李霞林, 郭力, 王成山. 微网主从控制模式下的稳定性分析[J]. 电工技术学报, 2014, 29(2): 24-34.
Li Xialin, Guo Li, Wang Chengshan. Stability Analysis in a Master-Slave Control Based Microgrid. Transactions of China Electrotechnical Society, 2014, 29(2): 24-34.
[1] 王成山, 肖朝霞, 王守相. 微网中分布式电源逆变器的多环反馈控制策略[J]. 电工技术学报, 2009, 24(2): 100-106. Wang Chengshan, Xiao Zhaoxia, Wang Shouxiang. Multiple Feedback loop control scheme for inverters of the micro source in microgrids[J]. Transactions of China Electrotechnical Society, 2009, 24(2): 100-106. [2] Loh P C, Li D, Chai Y K, et al. Hybrid AC-DC microgrids with energy storages and progressive energy flow tuning[J]. IEEE Transactions on Power Electronics, 2013, 28(4): 1533-1542. [3] 陆晓楠, 孙凯, 等. 适用于交直流混合微电网的直流分层控制系统[J]. 电工技术学报, 2013, 8(4): 3-42. Lu Xiaonan, Sun Kai, et al. DC hierarchical control system for microgrid applications[J]. Transactions of China Electrotechnical Society, 2013, 8(4): 3-42. [4] Wang C S, Li Y, Peng K, et al. Coordinated optimal design of inverter controllers in a micro-grid with multiple distributed generation units[J]. IEEE Transac- tions on Power Systems, 2013, 28(3): 2679-2686. [5] Pogaku N, Prodanovic M, Green T C. Modeling, analysis and testing of autonomous operation of an inverter-based microgrid[J]. IEEE Transactions on Power Electronics, 2007, 22(2): 613-624. [6] Iyer S V, Belur M N, Chandorkar M C. A generalized computational method to determine stability of a multi-inverter microgrid[J]. IEEE Transactions on Power Electronics, 2010, 25(9): 2420-2432. [7] Zhou X, Fan J W, Alex Q Huang. High-frequency resonance mitigation for plug-in hybrid electric vehicles’ integration with a wide range of grid conditions[J]. IEEE Transactions on Power Electronics, 2012, 27(11): 4459-4470. [8] 许津铭, 谢少军, 肖华锋. LCL滤波器有源阻尼控制机制研究[J]. 中国电机工程学报, 2012, 3(25): 27-32. Xu Jinming, Xie Shaojun, Xiao Huafeng. Research on control mechanism of active damping for LCL filters[J]. Proceedings of the CSEE, 2012, 3(25): 27-32. [9] 陆晓楠, 孙凯, 等. 微电网系统中基于双二阶滤波器的主动阻尼方法[J]. 电工技术学报, 2013, 28(3): 261-267. Lu Xiaonan, Sun Kai, et al. Active damping method based on bi-quad filter for microgrid applications[J]. Transactions of China Telectrotechnical Society, 2013, 28(3): 261-267. [10] Lu X N, Liserre M, Sun K, et al. Resonance propagation of parallel-operated DC-AC converters with LCL filters[C]. Applied Power Electronics Conference and Exposition(APEC), 2012: 877-883. [11] He J, Li Y W, Bosnjak D, et al. Investigation and active damping of multiple resonances in a parallel-inverter-based microgrid[J]. IEEE Transac- tions on Power Electronics, 2013, 28(1): 234-245. [12] Rodriguez P, Timbus A V, Blaabjerg F, et al. Flexible active power control of distributed power generation systems during grid faults[J]. IEEE Transactions on Power Electronics, 2007, 54(5): 2583-2591. [13] Weng S H, Chen Q, Cheng C K. Time-domain analysis of large-scale circuits by matrix exponen-tial method with adaptive control[J]. IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 2012, 31(8): 1180-1192. [14] Wang C S, Li X L, Guo L, et al. A seamless operation mode transition control strategy for a microgrid based on master-slave control[J]. Science China(Techno. Sciences), 2012, 55(6): 1644-1654. [15] 王成山, 李霞林, 郭力. 基于功率平衡及时滞补偿相结合的双级式变流器协调控制[J]. 中国电机工程学报, 2012, 32(25): 109-117. Wang Chengshan, Li Xialin, Guo Li. Coordinated control of two-stage power converters based on power balancing and time-delay compensation[J]. Procee- dings of the CSEE, 2012, 32(25): 109-117.
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