背靠背五电平二极管钳位型变流器直流环节的电压偏移机理及其载波调制均压策略
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摘要
直流电容的均压控制是多电平二极管钳位型变流器的技术难点。该文以背靠背五电平二极管钳位型变流器为例,首先分析不施加均压控制时变流器系统直流环节的电压偏移机理。其次,证明在整流侧和逆变侧分别注入零序电压,对直流环节各悬浮节点平均电流的影响。据此,建立背靠背五电平变流器系统的直流环节均压控制的数学模型,提出一种基于零序电压注入的主从协同均压控制策略,通过模型预测控制在线计算整流侧和逆变侧所需注入的零序电压。仿真和实验结果表明,在整流侧和逆变侧的不同调制比组合、不同基波频率及不同功率因数下,所提均压算法均具备良好的动态和稳态均压性能。
DC-link voltage balance control is the key problem of multilevel diode-clamped converters(DCCs). The back-to-back(BTB) five-level DCC was taken as an example.First, the voltage drift phenomenon of BTB five-level DCC system was mathematically analyzed when no voltage balance methods were employed. Then the effects of zero-sequence voltages on DC-link capacitors were proved, which were injected in both the rectifier and inverter sides. Accordingly, the voltage balance model for BTB five-level DCC system was established. To obtain the optimal zero-sequence voltages in both rectifier and inverter sides, a cascaded carrier-based voltage balance controller based on predictive control was developed. Simulation and experimental results prove that the proposed method can maintain the dc capacitors stable under different power factors, different fundamental frequencies and modulation index combinations of the rectifier and inverter.
DC-link voltage balance control is the key problem of multilevel diode-clamped converters(DCCs). The back-to-back(BTB) five-level DCC was taken as an example.First, the voltage drift phenomenon of BTB five-level DCC system was mathematically analyzed when no voltage balance methods were employed. Then the effects of zero-sequence voltages on DC-link capacitors were proved, which were injected in both the rectifier and inverter sides. Accordingly, the voltage balance model for BTB five-level DCC system was established. To obtain the optimal zero-sequence voltages in both rectifier and inverter sides, a cascaded carrier-based voltage balance controller based on predictive control was developed. Simulation and experimental results prove that the proposed method can maintain the dc capacitors stable under different power factors, different fundamental frequencies and modulation index combinations of the rectifier and inverter.
引文
[1]Kouro S,Malinowski M,Gopakumar K,et al.Recent advances and industrial applications of multilevel converters[J].IEEE Transactions on Industrial Electronics,2010,57(8):2553-2580.
[2]Mazuela M,Baraia I,Sanchez-Ruiz A,et al.DC-link voltage balancing strategy based on SVM and reactive power exchange for a 5L-MPC back-to-back converter for medium-voltage drives[J].IEEE Transactions on Industrial Electronics,2016,63(12):7864-7875.
[3]Akagi H,Fujita H,Yonetani S,et al.A 6.6-kVtransformerless STATCOM based on a five-level diodeclamped PWM converter:system design and experimentation of a 200-V 10-kVA laboratory model[J].IEEE Transactions on Industry Applications,2008,44(2):672-680.
[4]Shu Z L,He X Q,Wang Z Y,et al.Voltage balancing approaches for diode-clamped multilevel converters using auxiliary capacitor-based circuits[J].IEEE Transactions on Power Electronics,2013,28(5):2111-2124.
[5]Marchesoni M,Tenca P.Diode-clamped multilevel converters:a practicable way to balance DC-link voltages[J].IEEE Transactions on Industrial Electronics,2002,49(4):752-765.
[6]Shu Z L,Ding N,Chen J,et al.Multilevel SVPWM with dc-link capacitor voltage balancing control for diode-clamped multilevel converter based STATCOM[J].IEEE Transactions on Industrial Electronics,2013,60(5):1884-1896.
[7]王姿雅,罗隆福,许德伟.具备电容电压平衡和开关频率优化功能的五电平二极管钳位逆变器快速空间矢量调制[J].电工技术学报,2013,28(5):233-242.Wang Ziya,Luo Longfu,Xu Dewei.A fast SVM scheme for five-level diode-clamped inverters with balanced capacitor voltages and reduced switching frequency[J].Transactions of China Electrotechnical Society,2013,28(5):233-242(in Chinese).
[8]Khajehoddin S A,Bakhshai A,Jain P K.A simple voltage balancing scheme for m-level diode-clamped multilevel converters based on a generalized current flow model[J].IEEE Transactions on Power Electronics,2008,23(5):2248-2259.
[9]Saeedifard M,Iravani R,Pou J.Control and dc-capacitor voltage balancing of a space vector-modulated five-level STATCOM[J].IET Power Electronics,2009,2(3):203-215.
[10]Marchesoni M,Tenca P.Theoretical and practical limits in multilevel MPC inverters with passive front ends[C]//European Conference on Power Electronics and Applications.Graz,Austria,2001.
[11]Saeedifard M,Iravani R,Pou J.Analysis and control of dc-capacitor-voltage-drift phenomenon of a passive front-end five-level converter[J].IEEE Transactions on Industrial Electronics,2007,54(6):3255-3266.
[12]赵志宏,赵剑锋,沈凯安,等.二极管钳位型五电平逆变器高调制比高功率因数改进的均压方法[J].中国电机工程学报,2014,34(24):4022-4030.Zhao Zhihong,Zhao Jianfeng,Shen Kaian,et al.An improved dc-capacitor voltage balancing method for a five-level diode-clamped converter with high modulation index and high power factor[J].Proceedings of the CSEE,2014,34(24):4022-4030(in Chinese).
[13]李宁,王跃,厉肃,等.直流电容电压自平衡的新型五电平NPC变流器空间矢量调制策略[J].电工技术学报,2015,30(6):178-189.Li Ning,Wang Yue,Li Su,et al.DC capacitor voltage self-balancing space vector modulation strategy of fivelevel NPC converter[J].Transactions of China Electrotechnical Society,2015,30(6):178-189(in Chinese).
[14]Zhao Z H,Zhao J F,Huang C.An improved capacitor voltage-balancing method for five-level diode-clamped converters with high modulation index and high power factor[J].IEEE Transactions on Power Electronics,2016,31(4):3189-3202.
[15]Adam G P,Finney S J,Ojo O,et al.Quasi-two-level and three-level operation of a diode-clamped multilevel inverter using space vector modulation[J].IET Power Electronics,2012,5(5):542-551.
[16]Saeedifard M,Iravani R,Pou J.A space vector modulation strategy for a back-to-back five-level HVDC converter system[J].IEEE Transactions on Industrial Electronics,2009,56(2):452-466.
[17]Minshull S R,Bingham C,Stone D,et al.Frequency reduction schemes for back-to-back connected,diodeclamped multilevel converters[J].IET Power Electronics,2010,3(1):65-74.
[18]Chaves M,Margato E,Silva J F,et al.Fast optimum-predictive control and capacitor voltage balancing strategy for bipolar back-to-back NPCconverters in high-voltage direct current transmission systems[J].IET Generation,Transmission&Distribution,2011,5(3):368-375.
[19]Busquets-Monge S,Alepuz S,Rocabert J,et al.Pulse width modulations for the comprehensive capacitor voltage balance of n-level three-leg diode-clamped converters[J].IEEE Transactions on Power Electronics,2009,24(5):1364-1375.
[20]Pan Z G,Peng F Z.A sinusoidal PWM method with voltage balancing capability for diode-clamped five-level converters[J].IEEE Transactions on Industry Applications,2009,45(3):1028-1034.
[21]Fazio P,Maragliano G,Marchesoni M,et al.A new capacitor balancing technique in diode-clamped multilevel converters with active front end for extended operation range[C]//Proceedings of the 2011-14th European Conference on Power Electronics and Applications.Birmingham:IEEE,2011.
[22]Marchesoni M,Vaccaro L.Extending the operating range in diode-clamped multilevel inverters with active front ends[C]//2012 IEEE International Energy Conference and Exhibition.Florence:IEEE,2012:63-68.
[23]李国丽,史晓锋,姜卫东,等.二极管钳位型多电平逆变器脉宽调制时电容电压均衡方法[J].电工技术学报,2009,24(7):110-119.Li Guoli,Shi Xiaofeng,Jiang Weidong,et al.Unbalancing capacitor voltage for diode clamped multi-level inverter[J].Transactions of China Electrotechnical Society,2009,24(7):110-119(in Chinese).
[24]Grigoletto F B,Pinheiro H.Generalised pulse width modulation approach for DC capacitor voltage balancing in diode-clamped multilevel converters[J].IET Power Electronics,2011,4(1):89-100.
[25]Pan Z G,Peng F Z,Corzine K A,et al.Voltage balancing control of diode-clamped multilevel rectifier/inverter systems[J].IEEE Transactions on Industry Applications,2005,41(6):1698-1706.
[26]Busquets-Monge S,Filba-Martinez A,Alepuz S,et al.Amodulation strategy to operate multilevel multiphase diode-clamped and active-clamped DC-AC converters at low frequency modulation indices with dc-link capacitor voltage balance[J].IEEE Transactions on Power Electronics,2017,32(10):7521-7533.
[27]Liu Z,Wang Y,Tan G J,et al.A novel SVPWM algorithm for five-level active neutral-point-clamped converter[J].IEEE Transactions on Power Electronics,2016,31(5):3859-3866.
[28]Deng Y,Teo K H,Duan C J,et al.A fast and generalized space vector modulation scheme for multilevel inverters[J].IEEE Transactions on Power Electronics,2014,29(10):5204-5217.
[29]Vazquez S,Rodriguez J,Rivera M,et al.Model predictive control for power converters and drives:Advances and trends[J].IEEE Transactions on Industrial Electronics,2017,64(2):935-947.
[2]Mazuela M,Baraia I,Sanchez-Ruiz A,et al.DC-link voltage balancing strategy based on SVM and reactive power exchange for a 5L-MPC back-to-back converter for medium-voltage drives[J].IEEE Transactions on Industrial Electronics,2016,63(12):7864-7875.
[3]Akagi H,Fujita H,Yonetani S,et al.A 6.6-kVtransformerless STATCOM based on a five-level diodeclamped PWM converter:system design and experimentation of a 200-V 10-kVA laboratory model[J].IEEE Transactions on Industry Applications,2008,44(2):672-680.
[4]Shu Z L,He X Q,Wang Z Y,et al.Voltage balancing approaches for diode-clamped multilevel converters using auxiliary capacitor-based circuits[J].IEEE Transactions on Power Electronics,2013,28(5):2111-2124.
[5]Marchesoni M,Tenca P.Diode-clamped multilevel converters:a practicable way to balance DC-link voltages[J].IEEE Transactions on Industrial Electronics,2002,49(4):752-765.
[6]Shu Z L,Ding N,Chen J,et al.Multilevel SVPWM with dc-link capacitor voltage balancing control for diode-clamped multilevel converter based STATCOM[J].IEEE Transactions on Industrial Electronics,2013,60(5):1884-1896.
[7]王姿雅,罗隆福,许德伟.具备电容电压平衡和开关频率优化功能的五电平二极管钳位逆变器快速空间矢量调制[J].电工技术学报,2013,28(5):233-242.Wang Ziya,Luo Longfu,Xu Dewei.A fast SVM scheme for five-level diode-clamped inverters with balanced capacitor voltages and reduced switching frequency[J].Transactions of China Electrotechnical Society,2013,28(5):233-242(in Chinese).
[8]Khajehoddin S A,Bakhshai A,Jain P K.A simple voltage balancing scheme for m-level diode-clamped multilevel converters based on a generalized current flow model[J].IEEE Transactions on Power Electronics,2008,23(5):2248-2259.
[9]Saeedifard M,Iravani R,Pou J.Control and dc-capacitor voltage balancing of a space vector-modulated five-level STATCOM[J].IET Power Electronics,2009,2(3):203-215.
[10]Marchesoni M,Tenca P.Theoretical and practical limits in multilevel MPC inverters with passive front ends[C]//European Conference on Power Electronics and Applications.Graz,Austria,2001.
[11]Saeedifard M,Iravani R,Pou J.Analysis and control of dc-capacitor-voltage-drift phenomenon of a passive front-end five-level converter[J].IEEE Transactions on Industrial Electronics,2007,54(6):3255-3266.
[12]赵志宏,赵剑锋,沈凯安,等.二极管钳位型五电平逆变器高调制比高功率因数改进的均压方法[J].中国电机工程学报,2014,34(24):4022-4030.Zhao Zhihong,Zhao Jianfeng,Shen Kaian,et al.An improved dc-capacitor voltage balancing method for a five-level diode-clamped converter with high modulation index and high power factor[J].Proceedings of the CSEE,2014,34(24):4022-4030(in Chinese).
[13]李宁,王跃,厉肃,等.直流电容电压自平衡的新型五电平NPC变流器空间矢量调制策略[J].电工技术学报,2015,30(6):178-189.Li Ning,Wang Yue,Li Su,et al.DC capacitor voltage self-balancing space vector modulation strategy of fivelevel NPC converter[J].Transactions of China Electrotechnical Society,2015,30(6):178-189(in Chinese).
[14]Zhao Z H,Zhao J F,Huang C.An improved capacitor voltage-balancing method for five-level diode-clamped converters with high modulation index and high power factor[J].IEEE Transactions on Power Electronics,2016,31(4):3189-3202.
[15]Adam G P,Finney S J,Ojo O,et al.Quasi-two-level and three-level operation of a diode-clamped multilevel inverter using space vector modulation[J].IET Power Electronics,2012,5(5):542-551.
[16]Saeedifard M,Iravani R,Pou J.A space vector modulation strategy for a back-to-back five-level HVDC converter system[J].IEEE Transactions on Industrial Electronics,2009,56(2):452-466.
[17]Minshull S R,Bingham C,Stone D,et al.Frequency reduction schemes for back-to-back connected,diodeclamped multilevel converters[J].IET Power Electronics,2010,3(1):65-74.
[18]Chaves M,Margato E,Silva J F,et al.Fast optimum-predictive control and capacitor voltage balancing strategy for bipolar back-to-back NPCconverters in high-voltage direct current transmission systems[J].IET Generation,Transmission&Distribution,2011,5(3):368-375.
[19]Busquets-Monge S,Alepuz S,Rocabert J,et al.Pulse width modulations for the comprehensive capacitor voltage balance of n-level three-leg diode-clamped converters[J].IEEE Transactions on Power Electronics,2009,24(5):1364-1375.
[20]Pan Z G,Peng F Z.A sinusoidal PWM method with voltage balancing capability for diode-clamped five-level converters[J].IEEE Transactions on Industry Applications,2009,45(3):1028-1034.
[21]Fazio P,Maragliano G,Marchesoni M,et al.A new capacitor balancing technique in diode-clamped multilevel converters with active front end for extended operation range[C]//Proceedings of the 2011-14th European Conference on Power Electronics and Applications.Birmingham:IEEE,2011.
[22]Marchesoni M,Vaccaro L.Extending the operating range in diode-clamped multilevel inverters with active front ends[C]//2012 IEEE International Energy Conference and Exhibition.Florence:IEEE,2012:63-68.
[23]李国丽,史晓锋,姜卫东,等.二极管钳位型多电平逆变器脉宽调制时电容电压均衡方法[J].电工技术学报,2009,24(7):110-119.Li Guoli,Shi Xiaofeng,Jiang Weidong,et al.Unbalancing capacitor voltage for diode clamped multi-level inverter[J].Transactions of China Electrotechnical Society,2009,24(7):110-119(in Chinese).
[24]Grigoletto F B,Pinheiro H.Generalised pulse width modulation approach for DC capacitor voltage balancing in diode-clamped multilevel converters[J].IET Power Electronics,2011,4(1):89-100.
[25]Pan Z G,Peng F Z,Corzine K A,et al.Voltage balancing control of diode-clamped multilevel rectifier/inverter systems[J].IEEE Transactions on Industry Applications,2005,41(6):1698-1706.
[26]Busquets-Monge S,Filba-Martinez A,Alepuz S,et al.Amodulation strategy to operate multilevel multiphase diode-clamped and active-clamped DC-AC converters at low frequency modulation indices with dc-link capacitor voltage balance[J].IEEE Transactions on Power Electronics,2017,32(10):7521-7533.
[27]Liu Z,Wang Y,Tan G J,et al.A novel SVPWM algorithm for five-level active neutral-point-clamped converter[J].IEEE Transactions on Power Electronics,2016,31(5):3859-3866.
[28]Deng Y,Teo K H,Duan C J,et al.A fast and generalized space vector modulation scheme for multilevel inverters[J].IEEE Transactions on Power Electronics,2014,29(10):5204-5217.
[29]Vazquez S,Rodriguez J,Rivera M,et al.Model predictive control for power converters and drives:Advances and trends[J].IEEE Transactions on Industrial Electronics,2017,64(2):935-947.