非线性不平衡负载下四桥臂逆变器的控制策略
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摘要
电力电子变压器输出级逆变器与微电网中的离网逆变器输出特性直接受负载影响,交流负荷中含有大量的非线性与不平衡混合负载,会引起三相逆变器输出电压谐波畸变及不平衡,为了解决这个问题,提出了一种适用于三相四桥臂的电压不平衡和谐波抑制的混合控制策略。首先,基于四桥臂逆变器的数学模型,阐明了桥臂间的耦合关系;然后,详细分析了实现交流信号无差跟踪与抑制谐波对控制器工作性能的需求,并通过对伯德图的幅频特性分析,说明所提控制方法及参数选择的合理性。最后在αβ0坐标系下对非线性、不平衡混合负载接入下的逆变器进行仿真,验证了所提出控制策略及控制参数选择的正确性。
The output characteristics of power electronic transformer output stage inverter and off-grid inverter in microgrid are directly affected by loads. AC loads usually contain a large number of nonlinear and unbalanced mixed loads,which will cause harmonic distortion and imbalance of three-phase inverter output voltage. Aiming at solving those problems,a hybrid control strategy of three-phase four-leg inverter is proposed for unbalanced voltage compensation and harmonic suppression. Firstly,the coupling relationship among the four-leg is clarified,which is based on the mathematical model of the four-leg inverter. Then,the requirements for eliminating AC signal tracking error and suppressing harmonics are analyzed in detail. Meanwhile,the effectiveness of the proposed control method and parameter selection is illustrated by analyzing the amplitude-frequency characteristics of bode diagram. Finally,the correctness and validity of the proposed control strategy and selected control parameters for the inverter with nonlinear and unbalanced mixed load is verified by the simulation results in αβ0 coordinate.
The output characteristics of power electronic transformer output stage inverter and off-grid inverter in microgrid are directly affected by loads. AC loads usually contain a large number of nonlinear and unbalanced mixed loads,which will cause harmonic distortion and imbalance of three-phase inverter output voltage. Aiming at solving those problems,a hybrid control strategy of three-phase four-leg inverter is proposed for unbalanced voltage compensation and harmonic suppression. Firstly,the coupling relationship among the four-leg is clarified,which is based on the mathematical model of the four-leg inverter. Then,the requirements for eliminating AC signal tracking error and suppressing harmonics are analyzed in detail. Meanwhile,the effectiveness of the proposed control method and parameter selection is illustrated by analyzing the amplitude-frequency characteristics of bode diagram. Finally,the correctness and validity of the proposed control strategy and selected control parameters for the inverter with nonlinear and unbalanced mixed load is verified by the simulation results in αβ0 coordinate.
引文
[1]韩民晓,王皓界.直流微电网———未来供用电领域的重要模式[J].电气工程学报,2015,10(5):1-9.
[2]李瑞生,马凯琪,于芃,等.交直流混合微电网系统建模及协调控制研究[J].电测与仪表,2017,54(20):92-99.
[3] Huang A Q,Crow M L,Heydt G T,et al. The Future Re-newable Electric Energy Delivery and Management(FREEDM)System:The Energy Internet[J]. Proceedings of the IEEE,2010,99(1):133-148.
[4]段青,乐健,吕志鹏,等.利用电能路由器的配电网电能质量控制[J].电测与仪表,2017,54(14):57-63.
[5]魏金成,游芳,郭筱瑛,等.光伏发电系统中三相逆变器不平衡控制的分析[J].电测与仪表,2015,52(6):61-65.
[6]孟繁荣,曲林伟.基于前馈补偿控制的四桥臂逆变器研究[J].电测与仪表,2013,50(1):66-70.
[7] Zhang R,Prasad V H,Boroyevich D,et al. Three-dimensional space vector modulation for four-leg voltage-source con-verters[J]. IEEE Transactions on Power Electronics,2002,17(3):314-326.
[8] Vechiu I,Curea O,Camblong H. Transient Operation of a Four-Leg Inverter for Autonomous Applications With Un-balanced Load[J]. IEEE Transactions on Power Electronics,2010,25(2):399-407.
[9]王恒利,付立军,肖飞,等.三相逆变器不平衡负载条件下双环控制策略[J].电网技术,2013,37(2):398-404.
[10]韦徵,茹心芹,石伟,等.适用于不平衡负载工况下的微网逆变器控制策略[J].电力系统自动化,2016,40(20):76-82.
[11]邵宇,马海啸.一种三角波注入的三相四桥臂逆变器控制策略[J].电测与仪表,2014,51(19):81-85.
[12]刘秀翀,张化光,陈宏志.四桥臂逆变器中第四桥臂的控制策略[J].中国电机工程学报,2007,27(33):87-92.
[13]张晓勇,王军,李川,等.基于三维空间矢量中γ分量控制的三相四桥臂逆变器[J].电力自动化设备,2010,30(12):70-73.
[14]闫朝阳,白鹤,张喆,等.不平衡工况下基于虚拟阻抗法的并联三相四桥臂逆变器的桥臂控制[J].电工技术学报,2017,32(23):209-217.
[15]霍群海,孔力,唐西胜.微源逆变器不平衡非线性混合负载的控制[J].中国电机工程学报,2010,30(15):10-15.
[16]Lim K,Choi J,Jang J,et al. P+multiple resonant control for output voltage regulation of microgrid with unbalanced and nonlinear loads[C]//Power Electronics Conference. IEEE,2014:2656-2662.
[17]Hamzeh M,Karimi H,Mokhtari H. Harmonic and Nega-tive-Sequence Current Control in an Islanded Multi-Bus MV Microgrid[J]. IEEE Transactions on Smart Grid,2014,5(1):167-176.
[18]涂春鸣,杨义,肖凡,等.非线性负载下微电网主逆变器输出侧电能质量控制策略[J/OL].电工技术学报:1-9[2018-01-28]. https://doi. org/10. 19595/j. cnki. 1000-6753. tces. 170407.
[19]王亮,王冰,黄存荣.基于多PR控制的并网逆变器设计与参数整定[J].电网与清洁能源,2014,(7):45-51.
[2]李瑞生,马凯琪,于芃,等.交直流混合微电网系统建模及协调控制研究[J].电测与仪表,2017,54(20):92-99.
[3] Huang A Q,Crow M L,Heydt G T,et al. The Future Re-newable Electric Energy Delivery and Management(FREEDM)System:The Energy Internet[J]. Proceedings of the IEEE,2010,99(1):133-148.
[4]段青,乐健,吕志鹏,等.利用电能路由器的配电网电能质量控制[J].电测与仪表,2017,54(14):57-63.
[5]魏金成,游芳,郭筱瑛,等.光伏发电系统中三相逆变器不平衡控制的分析[J].电测与仪表,2015,52(6):61-65.
[6]孟繁荣,曲林伟.基于前馈补偿控制的四桥臂逆变器研究[J].电测与仪表,2013,50(1):66-70.
[7] Zhang R,Prasad V H,Boroyevich D,et al. Three-dimensional space vector modulation for four-leg voltage-source con-verters[J]. IEEE Transactions on Power Electronics,2002,17(3):314-326.
[8] Vechiu I,Curea O,Camblong H. Transient Operation of a Four-Leg Inverter for Autonomous Applications With Un-balanced Load[J]. IEEE Transactions on Power Electronics,2010,25(2):399-407.
[9]王恒利,付立军,肖飞,等.三相逆变器不平衡负载条件下双环控制策略[J].电网技术,2013,37(2):398-404.
[10]韦徵,茹心芹,石伟,等.适用于不平衡负载工况下的微网逆变器控制策略[J].电力系统自动化,2016,40(20):76-82.
[11]邵宇,马海啸.一种三角波注入的三相四桥臂逆变器控制策略[J].电测与仪表,2014,51(19):81-85.
[12]刘秀翀,张化光,陈宏志.四桥臂逆变器中第四桥臂的控制策略[J].中国电机工程学报,2007,27(33):87-92.
[13]张晓勇,王军,李川,等.基于三维空间矢量中γ分量控制的三相四桥臂逆变器[J].电力自动化设备,2010,30(12):70-73.
[14]闫朝阳,白鹤,张喆,等.不平衡工况下基于虚拟阻抗法的并联三相四桥臂逆变器的桥臂控制[J].电工技术学报,2017,32(23):209-217.
[15]霍群海,孔力,唐西胜.微源逆变器不平衡非线性混合负载的控制[J].中国电机工程学报,2010,30(15):10-15.
[16]Lim K,Choi J,Jang J,et al. P+multiple resonant control for output voltage regulation of microgrid with unbalanced and nonlinear loads[C]//Power Electronics Conference. IEEE,2014:2656-2662.
[17]Hamzeh M,Karimi H,Mokhtari H. Harmonic and Nega-tive-Sequence Current Control in an Islanded Multi-Bus MV Microgrid[J]. IEEE Transactions on Smart Grid,2014,5(1):167-176.
[18]涂春鸣,杨义,肖凡,等.非线性负载下微电网主逆变器输出侧电能质量控制策略[J/OL].电工技术学报:1-9[2018-01-28]. https://doi. org/10. 19595/j. cnki. 1000-6753. tces. 170407.
[19]王亮,王冰,黄存荣.基于多PR控制的并网逆变器设计与参数整定[J].电网与清洁能源,2014,(7):45-51.