具有主动阻尼特征的LCL并网逆变器状态反馈控制方法
|
摘要
网侧阻抗波动与数字控制延迟会影响到LCL滤波器型并网逆变电源的稳定运行。针对该问题,在考虑到数字延迟的基础上,建立系统的离散化状态空间模型,并进行状态反馈特征分析,据此研究一种具备主动阻尼特征的状态反馈控制方法。该方法将公共耦合点电压作为系统的状态变量,分析该状态变量反馈对网侧阻抗波动引入的稳定性问题的改善作用。另外,在仅对网侧电感电流采样的基础上,研究对逆变电流进行状态重构与离散系统状态拓展方法,并通过这些状态变量的反馈控制设计,改善系统的稳定裕度与参数适应性。通过仿真与实验进行验证,结果证明分析的正确性以及控制方法的可行性和有效性。
Based on discrete state space model analysis for LCL grid-connected inverter,an active damping method is proposed to settle down the stability problems caused by the grid impedance variation and the digital time delay.The common coupling point voltage vpcc is used as a system state,and its feedback characteristics is studied to reveal its damping effect.In addition,the states feedback characteristics of inverter current ii and grid current ig are evaluated respectively.Consequently,a state reconstruction method is provided,which relies on the sampling values of vpcc and ig.Meanwhile,the order of the space model is virtually enlarged to improve the system stability.The feasibility and effectiveness of the proposed control method are verified by Matlab/Simulink simulations and experiments.
Based on discrete state space model analysis for LCL grid-connected inverter,an active damping method is proposed to settle down the stability problems caused by the grid impedance variation and the digital time delay.The common coupling point voltage vpcc is used as a system state,and its feedback characteristics is studied to reveal its damping effect.In addition,the states feedback characteristics of inverter current ii and grid current ig are evaluated respectively.Consequently,a state reconstruction method is provided,which relies on the sampling values of vpcc and ig.Meanwhile,the order of the space model is virtually enlarged to improve the system stability.The feasibility and effectiveness of the proposed control method are verified by Matlab/Simulink simulations and experiments.
引文
[1]Hanif M,Khadkikar V,Xiao W,et al.Two degrees of freedom active damping technique for LCL filterbased grid connected PV systems[J].IEEE Transactions on Industrial Electronics,2014,61(6):2795-2803.
[2]Wang Jianguo,Yan Jiudun,Jiang Lin.Pseudoderivative-feedback current control for three-phase grid-connected inverters with LCL filters[J].IEEETransactions on Power Electronics,2016,31(5):3898-3912.
[3]Pan Donghua,Ruan Xinbo,Bao Chenlei,et al.Capacitor-current-feedback active damping with reduced computation delay for improving robustness of LCL-type grid-connected inverter[J].IEEETransactions on Power Electronics,2014,29(7):3414-3427.
[4]赵晋斌,张元吉,屈克庆,等.单相LCL并网逆变器控制策略综述[J].电工技术学报,2013,28(10):134-142.Zhao Jinbin,Zhang Yuanji,Qu Keqing,et al.Summary of control strategy for single-phase LCLgrid-connected[J].Transactions of China Electrotechnical Society,2013,28(10):134-142.
[5]侯朝勇,胡学浩,惠东.基于离散状态空间模型的LCL滤波并网变换器控制策略[J].中国电机工程学报,2011,31(36):8-15.Hou Chaoyong,Hu Xuehao,Hui Dong.Control strategy of grid-connected converter with LCL filter based on discrete state-space model[J].Proceedings of the CSEE,2011,31(36):8-15.
[6]Bao Chenlei,Ruan Xinbo,Wang Xuehua,et al.Stepby-step controller design for LCL-type gridconnected inverter with capacitor-current-feedback active-damping[J].IEEE Transactions on Power Electronics,2014,29(3):1239-1253.
[7]Xu Jinming,Xie Shaojun,Huang Liuliu,et al.Design of LCL-filter considering the control impact for gridconnected inverter with one current feedback only[J].IET Power Electronics,2017,10(11):1324-1332.
[8]Yin Jinjun,Duan Shanxu,Liu Bangyin.Stability analysis of grid-connected inverter with LCL filter adopting a digital single-loop controller with inherent damping characteristic[J].IEEE Transactions on Industrial Informatics,2013,9(2):1104-1112.
[9]Wang X,F Blaabjerg,P C Loh.Virtual RC damping of LCL-filtered voltage source converters with extended selective harmonic compensation[J].IEEETransactions on Power Electronics,2015,30(9):4726-4737.
[10]靳伟,李永丽,孙广宇.基于有源阻尼的并网逆变器电流内环H∞重复控制[J].中国电机工程学报,2016,36(17):4685-4693.Jin Wei,Li Yongli,Sun Guangyu.H∞repetitive current controllers for grid-connected inverters based on active damping[J].Proceedings of the CSEE,201636(17):4685-4693.
[11]庄超,叶永强,赵强松,等.基于分裂电容法的LCL并网逆变器控制策略分析与改进[J].电工技术学报,2015,30(16):85-93.Zhuang Chao,Ye Yongqiang,Zhao Qiangsong,et al.Analysis and improvement of LCL grid-connected inverter control strategy based on split capacitance method[J].Transactions of China Electrotechnical Society,2015,30(16):85-93.
[12]杨勇,赵方平,阮毅,等.三相并网逆变器模型电流预测控制[J].电工技术学报,2011,26(6):153-159.Yang Yong,Zhao Fangping,Ruan Yi,et al.The model current prediction control technology Threephase grid-connected inverter[J].Transactions of China Electrotechnical Society,2011,26(6):153-159.
[13]Zhen Xin,Wang Xiongfei,Poh Chiang Loh,et al.Grid-current-feedback control for LCL-filtered grid converters with enhanced stability[J].IEEE Transactions on Power Electronics,2017,32(4):3216-3228.
[14]Pan Donghua,Ruan Xinbo,Bao Chenlei,et al.Optimized controller design for LCL-type gridconnected inverter to achieve high robustness against grid-impedance variation[J].IEEE Transactions on Industrial Electronics,2015,62(3):1537-1547.
[15]Wang Jianguo,Yan Juidun,Jiang Lin,et al.Delaydependent stability of single-loop controlled gridconnected inverters with LCL filters[J].IEEETransactions on Power Electronics,2016,31(7):743-757.
[16]Xing Zhang,Peng Chen,Fei Li,et al.Study of a current control strategy based on multisampling for high-power grid-connected inverters with an LCLfilter[J].IEEE Transactions on Power Electronics,2017,32(7):5023-5034.
[17]Li Xiaoqiang,Fang Jingyang,Tang Yi,et al.Robust design of LCL filters for single-current-loop controlled grid-connected power converters with unit PCC voltage feedforward[J].IEEE Journal of Emerging and Selected Topics in Power Electronics,2017,6(1):54-72.
[18]Xu Jinming,Xie Shaojun,Qian Qiang,et al.Adaptive feedforward algorithm without grid impedance estimarion for inverters to suppress grid current instabilities and harmonics due to grid impedance and grid voltage distortion[J].IEEE Transactions on Industrial Electronics,2017,64(9):7574-7586.
[19]周乐明,罗安,陈燕东,等.LCL型并网逆变器的鲁棒并网电流反馈有源阻尼控制方法[J].中国电机工程学报,2016,36(10):2742-2752.Zhou Leming,Luo An,Chen Yandong,et al.A robust grid-current-feedback-active-damping method for LCL-type grid-connected inverters[J].Proceedings of the CSEE,2016,36(10):2742-2752.
[20]胡书举,龚文明,李丰林,等.一种并网逆变器无交流电压传感器控制策略研究[J].电工技术学报,2015,30(14):325-332.Hu Shuju,Gong Wenming,Li Fenglin,et al.Research on control strategy of a non-AC voltage sensor for grid-connected inverter[J].Transactions of China Electrotechnical Society,2015,30(14):325-332.
[21]Claudio A Busada,Sebastian Gomez Jorge.Full-state feedback equivalent controller for active damping LCL-filtered grid-connected inverters using a reduced number of sensors[J].IEEE Transactions on Industrial Electronics,2015,62(10):5993-6002.
[22]屈克庆,李文旗,叶天凯,等.基于状态反馈的LCL型逆变器解耦控制策略[J].电工技术学报2016,31(20):130-134.Qu Keqing,Li Wenqi,Ye Tiankai,et al.Decoupling control strategy of LCL inverter based on state feedback[J].Transactions of China Electrotechnical Society,2016,31(20):130-134.
[23]李宾,姚文熙,杭丽君,等.基于状态观测器的LCL滤波器型并网逆变器状态反馈最优化设计[J].电工技术学报,2014,29(6):80-90.Li Bin,Yao Wenxi,Hang Lijun,et al.Optimized design of state variable feedback of grid-connected inverter with LCL-filter based on state observer[J].Transactions of China Electrotechnical Society,2014,29(6):80-90.
[2]Wang Jianguo,Yan Jiudun,Jiang Lin.Pseudoderivative-feedback current control for three-phase grid-connected inverters with LCL filters[J].IEEETransactions on Power Electronics,2016,31(5):3898-3912.
[3]Pan Donghua,Ruan Xinbo,Bao Chenlei,et al.Capacitor-current-feedback active damping with reduced computation delay for improving robustness of LCL-type grid-connected inverter[J].IEEETransactions on Power Electronics,2014,29(7):3414-3427.
[4]赵晋斌,张元吉,屈克庆,等.单相LCL并网逆变器控制策略综述[J].电工技术学报,2013,28(10):134-142.Zhao Jinbin,Zhang Yuanji,Qu Keqing,et al.Summary of control strategy for single-phase LCLgrid-connected[J].Transactions of China Electrotechnical Society,2013,28(10):134-142.
[5]侯朝勇,胡学浩,惠东.基于离散状态空间模型的LCL滤波并网变换器控制策略[J].中国电机工程学报,2011,31(36):8-15.Hou Chaoyong,Hu Xuehao,Hui Dong.Control strategy of grid-connected converter with LCL filter based on discrete state-space model[J].Proceedings of the CSEE,2011,31(36):8-15.
[6]Bao Chenlei,Ruan Xinbo,Wang Xuehua,et al.Stepby-step controller design for LCL-type gridconnected inverter with capacitor-current-feedback active-damping[J].IEEE Transactions on Power Electronics,2014,29(3):1239-1253.
[7]Xu Jinming,Xie Shaojun,Huang Liuliu,et al.Design of LCL-filter considering the control impact for gridconnected inverter with one current feedback only[J].IET Power Electronics,2017,10(11):1324-1332.
[8]Yin Jinjun,Duan Shanxu,Liu Bangyin.Stability analysis of grid-connected inverter with LCL filter adopting a digital single-loop controller with inherent damping characteristic[J].IEEE Transactions on Industrial Informatics,2013,9(2):1104-1112.
[9]Wang X,F Blaabjerg,P C Loh.Virtual RC damping of LCL-filtered voltage source converters with extended selective harmonic compensation[J].IEEETransactions on Power Electronics,2015,30(9):4726-4737.
[10]靳伟,李永丽,孙广宇.基于有源阻尼的并网逆变器电流内环H∞重复控制[J].中国电机工程学报,2016,36(17):4685-4693.Jin Wei,Li Yongli,Sun Guangyu.H∞repetitive current controllers for grid-connected inverters based on active damping[J].Proceedings of the CSEE,201636(17):4685-4693.
[11]庄超,叶永强,赵强松,等.基于分裂电容法的LCL并网逆变器控制策略分析与改进[J].电工技术学报,2015,30(16):85-93.Zhuang Chao,Ye Yongqiang,Zhao Qiangsong,et al.Analysis and improvement of LCL grid-connected inverter control strategy based on split capacitance method[J].Transactions of China Electrotechnical Society,2015,30(16):85-93.
[12]杨勇,赵方平,阮毅,等.三相并网逆变器模型电流预测控制[J].电工技术学报,2011,26(6):153-159.Yang Yong,Zhao Fangping,Ruan Yi,et al.The model current prediction control technology Threephase grid-connected inverter[J].Transactions of China Electrotechnical Society,2011,26(6):153-159.
[13]Zhen Xin,Wang Xiongfei,Poh Chiang Loh,et al.Grid-current-feedback control for LCL-filtered grid converters with enhanced stability[J].IEEE Transactions on Power Electronics,2017,32(4):3216-3228.
[14]Pan Donghua,Ruan Xinbo,Bao Chenlei,et al.Optimized controller design for LCL-type gridconnected inverter to achieve high robustness against grid-impedance variation[J].IEEE Transactions on Industrial Electronics,2015,62(3):1537-1547.
[15]Wang Jianguo,Yan Juidun,Jiang Lin,et al.Delaydependent stability of single-loop controlled gridconnected inverters with LCL filters[J].IEEETransactions on Power Electronics,2016,31(7):743-757.
[16]Xing Zhang,Peng Chen,Fei Li,et al.Study of a current control strategy based on multisampling for high-power grid-connected inverters with an LCLfilter[J].IEEE Transactions on Power Electronics,2017,32(7):5023-5034.
[17]Li Xiaoqiang,Fang Jingyang,Tang Yi,et al.Robust design of LCL filters for single-current-loop controlled grid-connected power converters with unit PCC voltage feedforward[J].IEEE Journal of Emerging and Selected Topics in Power Electronics,2017,6(1):54-72.
[18]Xu Jinming,Xie Shaojun,Qian Qiang,et al.Adaptive feedforward algorithm without grid impedance estimarion for inverters to suppress grid current instabilities and harmonics due to grid impedance and grid voltage distortion[J].IEEE Transactions on Industrial Electronics,2017,64(9):7574-7586.
[19]周乐明,罗安,陈燕东,等.LCL型并网逆变器的鲁棒并网电流反馈有源阻尼控制方法[J].中国电机工程学报,2016,36(10):2742-2752.Zhou Leming,Luo An,Chen Yandong,et al.A robust grid-current-feedback-active-damping method for LCL-type grid-connected inverters[J].Proceedings of the CSEE,2016,36(10):2742-2752.
[20]胡书举,龚文明,李丰林,等.一种并网逆变器无交流电压传感器控制策略研究[J].电工技术学报,2015,30(14):325-332.Hu Shuju,Gong Wenming,Li Fenglin,et al.Research on control strategy of a non-AC voltage sensor for grid-connected inverter[J].Transactions of China Electrotechnical Society,2015,30(14):325-332.
[21]Claudio A Busada,Sebastian Gomez Jorge.Full-state feedback equivalent controller for active damping LCL-filtered grid-connected inverters using a reduced number of sensors[J].IEEE Transactions on Industrial Electronics,2015,62(10):5993-6002.
[22]屈克庆,李文旗,叶天凯,等.基于状态反馈的LCL型逆变器解耦控制策略[J].电工技术学报2016,31(20):130-134.Qu Keqing,Li Wenqi,Ye Tiankai,et al.Decoupling control strategy of LCL inverter based on state feedback[J].Transactions of China Electrotechnical Society,2016,31(20):130-134.
[23]李宾,姚文熙,杭丽君,等.基于状态观测器的LCL滤波器型并网逆变器状态反馈最优化设计[J].电工技术学报,2014,29(6):80-90.Li Bin,Yao Wenxi,Hang Lijun,et al.Optimized design of state variable feedback of grid-connected inverter with LCL-filter based on state observer[J].Transactions of China Electrotechnical Society,2014,29(6):80-90.