基于有源阻尼的单相LCL光伏并网逆变器优化控制器设计
|
摘要
LCL型滤波器广泛用于并网逆变器,然而,仅对注入电网电流控制,不能解决由LCL谐振峰值引起的电流谐波和低带宽问题。本文提出了一种并网LCL逆变器的主动阻尼(AD)控制方法,该方法仅基于注入到电网中的电流的反馈,反馈环节采用了一阶高通滤波器加一阶低通滤波器进行选频,从而抑制住谐振峰值。由于拓宽了反馈环节的带宽,此方法适用于电网阻抗引发的谐振频率偏移现象。同时,本文还采用一种带有阻尼的谐波补偿控制策略,并分析该策略对逆变器性能的影响,结果表明它可以有效抑制低频谐波,提高系统电网阻抗变化环境下的稳定性。通过MATLAB/Simulink仿真模拟与2kW实验平台验证了所提控制方法的有效性。
LCL filters are widely used in grid-connected inverters. However, the injected grid current control does not solve the problem of current harmonics and low bandwidth caused by the LCL resonance peak. The paper proposes an AD control method for LCL inverters, which is only based on the feedback of the grid current. The feedback loop uses the first-order HPF plus the first-order LPF for frequency selection, thereby suppressing the resonance peak. Due to the widening of the bandwidth of the feedback loop, this method is suitable for the resonance frequency shift phenomenon caused by the impedance of the grid. The paper also uses a harmonic compensation control strategy with damping, and analyzes the influence of this strategy on the performance of the inverter. The results show that it can effectively suppress low-frequency harmonics and improve the stability of the system under the impedance change environment. The effectiveness of the proposed control and design has been verified by MATLAB/Simulink simulation and 2 kW experimental platform.
LCL filters are widely used in grid-connected inverters. However, the injected grid current control does not solve the problem of current harmonics and low bandwidth caused by the LCL resonance peak. The paper proposes an AD control method for LCL inverters, which is only based on the feedback of the grid current. The feedback loop uses the first-order HPF plus the first-order LPF for frequency selection, thereby suppressing the resonance peak. Due to the widening of the bandwidth of the feedback loop, this method is suitable for the resonance frequency shift phenomenon caused by the impedance of the grid. The paper also uses a harmonic compensation control strategy with damping, and analyzes the influence of this strategy on the performance of the inverter. The results show that it can effectively suppress low-frequency harmonics and improve the stability of the system under the impedance change environment. The effectiveness of the proposed control and design has been verified by MATLAB/Simulink simulation and 2 kW experimental platform.
引文
[1] 梁毅,谢运祥,关远鹏(Liang Yi,Xie Yunxiang,Guan Yuanpeng).LCL并网逆变器双闭环控制策略及其参数设计(Double closed-loop control strategy and parameter design of LCL grid-connected inverter)[J].电工电能新技术(Advanced Technology of Electrical Engineering and Energy),2018,38(4):30-38.
[2] 刘飞,查晓明,段善旭(Liu Fei,Zha Xiaoming,Duan Shanxu).三相并网逆变器LCL滤波器的参数设计与研究(Parameter design and research of three-phase grid-connected inverter LCL filter)[J].电工技术学报(Transactions of China Electrotechnical Society),2010,25(3):110-116.
[3] 鲍陈磊,阮新波,王学华,等(Bao Chenlei,Ruan Xinbo,Wang Xuehua,et al.).基于PI调节器和电容电流反馈有源阻尼的LCL型并网逆变器闭环参数设计(Closed-loop parameter design of LCL-type grid-connected inverter based on PI regulator and capacitive current feedback active damping)[J].中国电机工程学报(Proceedings of the CSEE),2012,32(25):133-142.
[4] 胡雪峰,韦徵,陈轶涵,等(Hu Xuefeng,Wei Zheng,Chen Yihan,et al.).LCL滤波并网逆变器的控制策略(Control strategy of LCL filtered grid-connected inverter)[J].中国电机工程学报(Proceedings of the CSEE),2012,32(27):142-148.
[5] Miskovic V,Blasko V,Jahns T,et al.Observer-based active damping of LCL resonance in grid-connected voltage source converters[J].IEEE Transactions on Industry Applications,2014,50(6):3977-3985.
[6] 王海松,王晗,张建文,等(Wang Haisong,Wang Han,Zhang Jianwen,et al.).LCL型并网逆变器的分裂电容无源阻尼控制(Split-capacitor passive damping control of LCL grid-connected inverter)[J].电网技术(Power System Technology),2014,38(4):895-902.
[7] 雷一,赵争鸣,鲁思兆(Lei Yi,Zhao Zhengming,Lu Sizhao).LCL滤波的光伏并网逆变器有源阻尼与无源阻尼混合控制(LCL-filtered photovoltaic grid-connected inverter active damping and passive damping hybrid control)[J].电力自动化设备(Electric Power Automation Equipment),2012,32(11):23-27.
[8] 许晓笛,李子欣,楚遵方,等(Xu Xiaodi,Li Zixin,Chu Zunfang,et al.).三相四线三电平APF并联运行有源阻尼方法(Active damping method for three-phase,four-wire and three-level APF parallel operation)[J].电工电能新技术(Advanced Technology of Electrical Engineering and Energy),2017,36(7):16-23.
[9] Geng Y,Yun Y,Chen R,et al.Parameters design and optimization for LC-type off-grid inverter with inductor-current-feedback active-damping [J].IEEE Transactions on Power Electronics,2018,33(1):703-715.
[10] 李宗鉴,戴瑜兴,郑崇伟,等(Li Zongjian,Dai Yuxing,Zheng Chongwei,et al.).单相并网变流器的离散PR控制设计(Design of discrete PR control for single-phase grid-connected converter)[J].现代电子技术(Modern Electronic Technology),2014,37(17):154-156.
[11] Zhang X,Chen P,Yu C,et al.Study of current control strategy based on multi-sampling for high-power grid-connected inverters with LCL-filter[J].IEEE Transactions on Power Electronics,2017,32(7):5023-5034.
[12] Xu J,Xie S,Tang T.Active damping-based control for grid-connected LCL-filtered inverter with injected grid current feedback only [J].IEEE Transactions on Industrial Electronics,2014,61(9):4746-4758.
[13] 周乐明,杨苓,陈燕东,等(Zhou Leming,Yang Ling,Chen Yandong,et al.).降低谐振频率偏差和电网阻抗影响的单逆变器电流反馈谐振抑制方法(Single inverter current feedback resonance suppression method for reducing resonance frequency deviation and grid impedance)[J].中国电机工程学报(Proceedings of the CSEE),2018,38(15):4490-4503.
[14] 滕宇,王学华,余辉,等(Teng Yu,Wang Xuehua,Yu Hui,et al.).提高LCL型并网逆变器对电网阻抗鲁棒性的阻抗调节方法(Impedance adjustment method for improving the robustness of LCL type grid-connected inverter to grid impedance)[J].中国电机工程学报(Proceedings of the CSEE),2015,35(Suppl.):197-204.
[15] IEEE Std 519-1992,IEEE recommended practices and requirements for harmonic control in electrical power systems[S].
[16] 尹靖元,金新民,吴学智,等(Yin Jingyuan,Jin Xinmin,Wu Xuezhi,et al.).基于带通滤波器的LCL型滤波器有源阻尼控制(Active damping control of LCL type filter based on bandpass filter)[J].电网技术(Power System Technology),2013,37(8):2376-2382.
[17] 李建林,徐少华,惠东(Li Jianlin,Xu Shaohua,Hui Dong).一种适合于储能PCS的PI与准PR控制策略研究(A PI and quasi-PR control strategy for energy storage PCS)[J].电工电能新技术(Advanced Technology of Electrical Engineering and Energy),2016,35(2):54-61.
[2] 刘飞,查晓明,段善旭(Liu Fei,Zha Xiaoming,Duan Shanxu).三相并网逆变器LCL滤波器的参数设计与研究(Parameter design and research of three-phase grid-connected inverter LCL filter)[J].电工技术学报(Transactions of China Electrotechnical Society),2010,25(3):110-116.
[3] 鲍陈磊,阮新波,王学华,等(Bao Chenlei,Ruan Xinbo,Wang Xuehua,et al.).基于PI调节器和电容电流反馈有源阻尼的LCL型并网逆变器闭环参数设计(Closed-loop parameter design of LCL-type grid-connected inverter based on PI regulator and capacitive current feedback active damping)[J].中国电机工程学报(Proceedings of the CSEE),2012,32(25):133-142.
[4] 胡雪峰,韦徵,陈轶涵,等(Hu Xuefeng,Wei Zheng,Chen Yihan,et al.).LCL滤波并网逆变器的控制策略(Control strategy of LCL filtered grid-connected inverter)[J].中国电机工程学报(Proceedings of the CSEE),2012,32(27):142-148.
[5] Miskovic V,Blasko V,Jahns T,et al.Observer-based active damping of LCL resonance in grid-connected voltage source converters[J].IEEE Transactions on Industry Applications,2014,50(6):3977-3985.
[6] 王海松,王晗,张建文,等(Wang Haisong,Wang Han,Zhang Jianwen,et al.).LCL型并网逆变器的分裂电容无源阻尼控制(Split-capacitor passive damping control of LCL grid-connected inverter)[J].电网技术(Power System Technology),2014,38(4):895-902.
[7] 雷一,赵争鸣,鲁思兆(Lei Yi,Zhao Zhengming,Lu Sizhao).LCL滤波的光伏并网逆变器有源阻尼与无源阻尼混合控制(LCL-filtered photovoltaic grid-connected inverter active damping and passive damping hybrid control)[J].电力自动化设备(Electric Power Automation Equipment),2012,32(11):23-27.
[8] 许晓笛,李子欣,楚遵方,等(Xu Xiaodi,Li Zixin,Chu Zunfang,et al.).三相四线三电平APF并联运行有源阻尼方法(Active damping method for three-phase,four-wire and three-level APF parallel operation)[J].电工电能新技术(Advanced Technology of Electrical Engineering and Energy),2017,36(7):16-23.
[9] Geng Y,Yun Y,Chen R,et al.Parameters design and optimization for LC-type off-grid inverter with inductor-current-feedback active-damping [J].IEEE Transactions on Power Electronics,2018,33(1):703-715.
[10] 李宗鉴,戴瑜兴,郑崇伟,等(Li Zongjian,Dai Yuxing,Zheng Chongwei,et al.).单相并网变流器的离散PR控制设计(Design of discrete PR control for single-phase grid-connected converter)[J].现代电子技术(Modern Electronic Technology),2014,37(17):154-156.
[11] Zhang X,Chen P,Yu C,et al.Study of current control strategy based on multi-sampling for high-power grid-connected inverters with LCL-filter[J].IEEE Transactions on Power Electronics,2017,32(7):5023-5034.
[12] Xu J,Xie S,Tang T.Active damping-based control for grid-connected LCL-filtered inverter with injected grid current feedback only [J].IEEE Transactions on Industrial Electronics,2014,61(9):4746-4758.
[13] 周乐明,杨苓,陈燕东,等(Zhou Leming,Yang Ling,Chen Yandong,et al.).降低谐振频率偏差和电网阻抗影响的单逆变器电流反馈谐振抑制方法(Single inverter current feedback resonance suppression method for reducing resonance frequency deviation and grid impedance)[J].中国电机工程学报(Proceedings of the CSEE),2018,38(15):4490-4503.
[14] 滕宇,王学华,余辉,等(Teng Yu,Wang Xuehua,Yu Hui,et al.).提高LCL型并网逆变器对电网阻抗鲁棒性的阻抗调节方法(Impedance adjustment method for improving the robustness of LCL type grid-connected inverter to grid impedance)[J].中国电机工程学报(Proceedings of the CSEE),2015,35(Suppl.):197-204.
[15] IEEE Std 519-1992,IEEE recommended practices and requirements for harmonic control in electrical power systems[S].
[16] 尹靖元,金新民,吴学智,等(Yin Jingyuan,Jin Xinmin,Wu Xuezhi,et al.).基于带通滤波器的LCL型滤波器有源阻尼控制(Active damping control of LCL type filter based on bandpass filter)[J].电网技术(Power System Technology),2013,37(8):2376-2382.
[17] 李建林,徐少华,惠东(Li Jianlin,Xu Shaohua,Hui Dong).一种适合于储能PCS的PI与准PR控制策略研究(A PI and quasi-PR control strategy for energy storage PCS)[J].电工电能新技术(Advanced Technology of Electrical Engineering and Energy),2016,35(2):54-61.