Synchronization optimization method of adaptive frequency-locked loop without DC component interference
-
摘要:
电网同步是提高并网换流器故障穿越能力的关键技术之一。为实现电网不平衡下换流器快速准确的并网跟踪，提出一种改进的一阶广义积分器锁频环（FOGI-FLL）方法。建立并网换流器数学模型，分析了不平衡电网下的正负序分离原理，并给出了正负序基频分量分离简化结构，讨论了简化结构中一阶广义积分器核心模块的实现方法，在一阶广义积分器滤波结构上进行了改进，增加了可以消除直流分量干扰的积分补偿环节。仿真结果表明，本文所提方法在电网电压不平衡环境中可以实现高性能的同步跟踪效果。
Abstract:Grid synchronization is one of the key technologies to improve the fault ride-through capability for grid-connected converter. To achieve fast and accurate phase or frequency tracking under unbalanced grid voltage, a kind of improved first-order generalized integrator based on frequency-locked loop (FOGI-FLL) method is put forward. A mathematical model of grid-connected converter is established. Its separation principle of positive and negative sequences under unbalanced grid is also analyzed. The separation structure of fundamental negative and positive sequence components is simplified. Its core module configuration of FOGI is discussed. Integral compensation function which can eliminate the interference of DC components for FLL tracking is parallelly added to the basic structure of FOGI filter. Finally, the proposed method is verified by contrast simulation under unbalanced grid voltage with DC components. Simulation results present that the proposed method is capable of achieving better performance for synchronization under unbalanced grid voltage.
-
图 2 正负序基频分量分离结构
Figure 2. Separation structure of fundamental positive and negative sequence components
图 4 FOGI分离+50 Hz幅频图
Figure 4. Amplitude frequency diagram of separating +50 Hz based on FOGI
图 11 正负序电压分量分离波形
Figure 11. Separation waveforms of positive and negative sequence voltage component
-
[1] KARIMI G M, MOJIRI M, SAFAEE A, et al.A new phase-locked loop system for three-phase applications[J].IEEE Transactions on Power Electronics, 2013, 28(3):1208-1218. doi: 10.1109/TPEL.2012.2207967 [2] ESCOBAR G, PETTERSSON S, HO C N M.Phase-locked loop for grid synchronization under unbalanced operation and harmonic distortion[C]//IECON 2011-37th Annual Conference on IEEE Industrial Electronics Society.Piscataway, NJ:IEEE Press, 2011:675-680. [3] REYES M, RODRIGUEZ P, VAZQUEZ S, et al.Enhanced decoupled double synchronous reference frame current controller for unbalanced grid-voltage conditions[J].IEEE Transactions on Power Electronics, 2012, 27(9):3934-3943. doi: 10.1109/TPEL.2012.2190147 [4] 黎金英, 艾欣, 邓玉辉.微电网电压不平衡的分层补偿控制策略[J].哈尔滨工业大学学报, 2016, 48(3):46-52. doi: 10.11918/j.issn.0367-6234.2016.03.008LI J Y, AI X, DENG Y H.Hierarchical control strategy for voltage unbalance compensation in micro-grid[J].Journal of Harbin Institute of Technology, 2016, 48(3):46-52(in Chinese). doi: 10.11918/j.issn.0367-6234.2016.03.008 [5] 丁稳房, 李志鹏, 余佳佳, 等.基于光伏并网逆变器锁相环技术研究[J].湖北工业大学学报, 2015, 30(1):5-7. http://cdmd.cnki.com.cn/Article/CDMD-10109-1013183595.htmDING W F, LI Z P, YU J J, et al.On the phase-locked loop technology based on photovoltaic grid inverters[J].Journal of Hebei University of Technology, 2015, 30(1):5-7(in Chinese). http://cdmd.cnki.com.cn/Article/CDMD-10109-1013183595.htm [6] RANI B I, ARAVIND C K, ILANGO G S, et al.A three phase PLL with a dynamic feed forward frequency estimator for synchronization of grid connected converters under wide frequency variations[J].International Journal of Electrical Power & Energy Systems, 2012, 41(1):63-70. http://www.sciencedirect.com/science/article/pii/S0142061512000634 [7] RODRIGUEZ P, LUNA A, MUNOZ R S, et al.A stationary reference frame grid synchronization system for three-phase grid-connected power converters under adverse grid conditions[J].IEEE Transactions on Power Electronics, 2012, 27(1):99-112. doi: 10.1109/TPEL.2011.2159242 [8] 赵新, 金新民, 周飞, 等.采用降阶谐振调节器的并网逆变器锁频环技术[J].中国电机工程学报, 2013, 33(15):38-44. http://www.cnki.com.cn/Article/CJFDTOTAL-ZGDC201315004.htmZHAO X, JIN X M, ZHOU F, et al.A frequency-locked loop technology of grid-connected inverters based on the reduced order resonant controller[J].Proceedings of the CSEE, 2013, 33(15):38-44(in Chinese). http://www.cnki.com.cn/Article/CJFDTOTAL-ZGDC201315004.htm [9] GUO X, WU W, CHEN Z.Multiple-complex coefficient-filter-based phase-locked loop and synchronization technique for three-phase grid-interfaced converters in distributed utility networks[J].IEEE Transactions on Industrial Electronics, 2011, 58(4):1194-1204. doi: 10.1109/TIE.2010.2041738 [10] 郭小强, 邬伟扬, 漆汉宏.电网电压畸变不平衡情况下三相光伏并网逆变器控制策略[J].中国电机工程学报, 2013, 33(3):22-28. http://www.cnki.com.cn/Article/CJFDTOTAL-ZGDC201303003.htmGUO X Q, WU W Y, QI H H.Control strategies of three-phase PV grid-connected inverter under distorted and unbalanced voltage conditions[J].Proceedings of the CSEE, 2013, 33(3):22-28(in Chinese). http://www.cnki.com.cn/Article/CJFDTOTAL-ZGDC201303003.htm [11] RODRIGUEZ P, LUNA A, MUÑOZ-AGUILAR R S, et al.A stationary reference frame grid synchronization system for three-phase grid-connected power converters under adverse grid conditions[J].IEEE Transactions on Power Electronics, 2012, 27(1):99-112. doi: 10.1109/TPEL.2011.2159242 [12] BUSADA C A, JORGE S G, LEON A E, et al.Current controller based on reduced order generalized integrators for distributed generation systems[J].IEEE Transactions on Industrial Electronics, 2012, 59(7):2898-2909. doi: 10.1109/TIE.2011.2167892 [13] 刘鸿鹏, 王卫, 吴辉.光伏逆变器的调制方式分析与直流分量抑制[J].中国电机工程学报, 2010, 30(9):27-32. http://www.cnki.com.cn/Article/CJFDTOTAL-ZGDC201009005.htmLIU H P, WANG W, WU H.Modulation mode analysis and suppressing DC current of PV inverter[J].Proceedings of the CSEE, 2010, 30(9):27-32(in Chinese). http://www.cnki.com.cn/Article/CJFDTOTAL-ZGDC201009005.htm [14] CIOBOTARU M, TEODORESCU R, AGELIDIS V G.Offset rejection for PLL based synchronization in grid-connected converters[C]//IEEE Applied Power Electronics Conference and Exposition.Piscataway, NJ:IEEE Press, 2008:1611-1617. [15] KARIMI G M, KHAJEHODDIN S A, JAIN P K, et al.Addressing DC component in PLL and notch filter algorithms[J].IEEE Transactions on Power Electronics, 2012, 27(1):78-86. doi: 10.1109/TPEL.2011.2158238 -
下载:
点击查看大图
计量
- 文章访问数: 1060
- HTML全文浏览量: 239
- PDF下载量: 628
- 被引次数: 0
