基于离散迭代模型的DAB变换器等效电路研究
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摘要
双有源全桥(dual active bridge,DAB)变换器能适应直流供电系统中诸多应用场合的需求,作为一种通用变换器,受到广泛关注。通过对其状态转移函数进行等效变换和近似处理,提出一种基于离散迭代模型的DAB变换器等效电路。与传统的降阶等效电路相比,该文所提出的等效电路能同时刻画变换器的电感电流和电容电压的动态,从而避免模型降阶带来的误差,兼具准确性和直观性。在此基础上,分析导通回路上寄生电阻对其功率传输特性的影响,从而更加精确地刻画DAB的稳态特性;然后,考察等效电路在离散域中状态方程的特征根,得到变换器的稳定边界;并且全面分析端口参数(输入电压和负载)与特征根模值的关系,从而得出运行条件对稳定裕度的影响。仿真和实验结果都表明该等效电路的精确性和通用性以及分析结论的正确性。
The dual active bridge(DAB) converter can meet various requirements of the DC power supply system.Then, it can be a general solution for various applications. By approximating the state transition function of DAB converter,this paper developed a discrete-time model based equivalent circuit. In contrast with conventional reduced-order equivalent circuit of DAB converter, the proposed circuit-oriented model can depict the dynamics of the inductor current and the output voltage simultaneously, thereby avoiding the modeling error caused by model simplification. And the resulting model can achieve good combination of accuracy and intuitiveness. On this basis, the equivalent circuit facilitated to derive an improved steady-state expression that offered more accurate predictions of DAB DC characteristics by considering the influence induced by the parasitic resistance upon the output voltage. By investigating the eigenvalues of the state equation of the equivalent circuit, the stability boundary can be obtained. Additionally, it was comprehensively investigated how the input voltage and the load affect the eigenvalues. Therefore, the influence provided by the operating condition upon the stability margin can be concluded.Finally, simulations and experimental measurements provide verification of the proposed equivalent circuit.
The dual active bridge(DAB) converter can meet various requirements of the DC power supply system.Then, it can be a general solution for various applications. By approximating the state transition function of DAB converter,this paper developed a discrete-time model based equivalent circuit. In contrast with conventional reduced-order equivalent circuit of DAB converter, the proposed circuit-oriented model can depict the dynamics of the inductor current and the output voltage simultaneously, thereby avoiding the modeling error caused by model simplification. And the resulting model can achieve good combination of accuracy and intuitiveness. On this basis, the equivalent circuit facilitated to derive an improved steady-state expression that offered more accurate predictions of DAB DC characteristics by considering the influence induced by the parasitic resistance upon the output voltage. By investigating the eigenvalues of the state equation of the equivalent circuit, the stability boundary can be obtained. Additionally, it was comprehensively investigated how the input voltage and the load affect the eigenvalues. Therefore, the influence provided by the operating condition upon the stability margin can be concluded.Finally, simulations and experimental measurements provide verification of the proposed equivalent circuit.
引文
[1]李娟.基于双有源桥的并网双向AC/DC变换器技术研究[D].南京:南京航空航天大学,2015.Li Juan.Research on dual-active-bridge-based grid-tied bidirectional ac/dc converter[D].Nanjing:Nanjing University of Aeronautics and Astronautics,2015(in Chinese).
[2]李建国,赵彪,宋强,等.适用于直流微电网的开关电容接入式双主动移相变换器[J].中国电机工程学报,2017,37(17):4922-4930,5211.Li Jianguo,Zhao Biao,Song Qiang,et al.Dual active bridge converter based on switched capacitor access in micro-grid DC distribution system[J].Proceedings of the CSEE,2017,37(17):4922-4930,5211(in Chinese).
[3]宋强,赵彪,刘文华,等.智能直流配电网研究综述[J].中国电机工程学报,2013,33(25):9-19.Song Qiang,Zhao Biao,Liu Wenhua,et al.An overview of research on smart DC distribution power network[J].Proceedings of the CSEE,2013,33(25):9-19(in Chinese).
[4]Kheraluwala M N,Gascoigne R W,Divan D M,et al.Performance characterization of a high-power dual active bridge DC-to-DC converter[J].IEEE Transactions on Industry Applications,1992,28(6):1294-1301.
[5]Burkart R M,Kolar J W.Comparativeη-ρ-σpareto optimization of Si and SiC multilevel dual-active-bridge topologies with wide input voltage range[J].IEEETransactions on Power Electronics,2017,32(7):5258-5270.
[6]宋强,赵彪,刘文华,等.智能电网中的新一代高频隔离功率转换技术[J].中国电机工程学报,2014,34(36):6369-6379.Song Qiang,Zhao Biao,Liu Wenhua,et al.Next-generation high-frequency-isolation power conversion technology for smart grid[J].Proceedings of the CSEE,2014,34(36):6369-6379(in Chinese).
[7]郭灵瑜,姚钢,周荔丹.全直流海上风电场高升压比DC/DC变换技术综述[J].电力系统保护与控制,2018,46(12):158-69.Guo Lingyu,Yao Gang,Zhou Lidan.Research review on high step-up ratio DC/DC converter for offshore DC wind farm[J].Power System Protection and Control,2018,46(12):158-69(in Chinese).
[8]Middlebrook R D,Cuk S.A general unified approach to modelling switching-converter power stages[C]//1976IEEE Power Electronics Specialists Conference.Cleveland,OH,USA:IEEE,1976:18-34.
[9]Krismer F,Kolar J W.Accurate small-signal model for the digital control of an automotive bidirectional dual active bridge[J].IEEE Transactions on Power Electronics,2009,24(12):2756-2768.
[10]Sanders S R,Noworolski J M,Liu X Z,et al.Generalized averaging method for power conversion circuits[J].IEEETransactions on Power Electronics1991,6(2):251-259.
[11]Caliskan V A,Verghese O C,Stankovic AM.Multi-frequency averaging of DC/DC converters[J].IEEETransactions on Power Electronics,1999,14(1):124-133.
[12]Qin Hengsi,Kimball J W.Generalized average modeling of dual active bridge DC-DC converter[J].IEEETransactions on Power Electronics,2012,27(4):2078-2084.
[13]Li Zhuoqiang,Wang Yue,Shi Ling,et al.Generalized averaging modeling and control strategy for three-phase dual-active-bridge DC-DC converters with three control variables[C]//2017 IEEE Applied Power Electronics Conference and Exposition(APEC).Tampa,FL,USA:IEEE,2017:1078-1084.
[14]Verghese G C,Elbuluk M E,Kassakian J G.A general approach to sampled-data modeling for power electronic circuits[J].IEEE Transactions on Power Electronics,1986,PE-1(2):76-89.
[15]Costinett D.Reduced order discrete time modeling of ZVS transition dynamics in the dual active bridge converter[C]//2015 IEEE Applied Power Electronics Conference and Exposition(APEC).Charlotte,NC,USA:IEEE,2015:365-370.
[16]Shi Ling,Lei Wanjun,Huang Jun,et al.Full discrete-time modeling and stability analysis of the digital controlled dual active bridge converter[C]//2016 IEEE 8th International Power Electronics and Motion Control Conference(IPEMC-ECCE Asia).Hefei,China:IEEE,2016:3813-3817.
[17]Costinett D,Zane R,Maksimovi?D.Discrete-time small-signal modeling of a 1 MHz efficiency-optimized dual active bridge converter with varying load[C]//2012IEEE 13th Workshop on Control and Modeling for Power Electronics(COMPEL).Kyoto,Japan:IEEE,2012:1-7.
[18]Alonso A R,Sebastian J,Lamar D G,et al.An overall study of a dual active bridge for bidirectional DC/DCconversion[C]//2010 IEEE Energy Conversion Congress and Exposition.Atlanta,GA,USA:IEEE,2010:1129-1135.
[19]Zhang Kai,Shan Zhenyu,Jatskevich J.Large-and small-signal average-value modeling of dual-active-bridge DC-DC converter considering power losses[J].IEEETransactions on Power Electronics,2017,32(3):1964-1974.
[20]黄珺,王跃,李卓强,等.基于三重移相控制的双主动全桥直流变换器优化调制策略[J].中国电机工程学报,2016,36(6):1658-1666.Huang Jun,Wang Yue,Li Zhuoqiang,et al.Optimized modulation scheme of dual active bridge DC-DCconverter based on triple-phase-shift control[J].Proceedings of the CSEE,2016,36(6):1658-1666(in Chinese).
[21]Zhang Fan,Ur Rehman M M,Zane R,et al.Improved steady-state model of the dual-active-bridge converter[C]//2015 IEEE Energy Conversion Congress and Exposition(ECCE).Montreal,QC,Canada:IEEE,2015:630-636.
[22]Mattavelli P,Spiazzi G,Tenti P.Predictive digital control of power factor preregulators with input voltage estimation using disturbance observers[J].IEEETransactions on Power Electronics,2005,20(1):140-147.
[23]Elaydi S.An introduction to difference equations[M].3rd ed.New York:Springer,2005.
[2]李建国,赵彪,宋强,等.适用于直流微电网的开关电容接入式双主动移相变换器[J].中国电机工程学报,2017,37(17):4922-4930,5211.Li Jianguo,Zhao Biao,Song Qiang,et al.Dual active bridge converter based on switched capacitor access in micro-grid DC distribution system[J].Proceedings of the CSEE,2017,37(17):4922-4930,5211(in Chinese).
[3]宋强,赵彪,刘文华,等.智能直流配电网研究综述[J].中国电机工程学报,2013,33(25):9-19.Song Qiang,Zhao Biao,Liu Wenhua,et al.An overview of research on smart DC distribution power network[J].Proceedings of the CSEE,2013,33(25):9-19(in Chinese).
[4]Kheraluwala M N,Gascoigne R W,Divan D M,et al.Performance characterization of a high-power dual active bridge DC-to-DC converter[J].IEEE Transactions on Industry Applications,1992,28(6):1294-1301.
[5]Burkart R M,Kolar J W.Comparativeη-ρ-σpareto optimization of Si and SiC multilevel dual-active-bridge topologies with wide input voltage range[J].IEEETransactions on Power Electronics,2017,32(7):5258-5270.
[6]宋强,赵彪,刘文华,等.智能电网中的新一代高频隔离功率转换技术[J].中国电机工程学报,2014,34(36):6369-6379.Song Qiang,Zhao Biao,Liu Wenhua,et al.Next-generation high-frequency-isolation power conversion technology for smart grid[J].Proceedings of the CSEE,2014,34(36):6369-6379(in Chinese).
[7]郭灵瑜,姚钢,周荔丹.全直流海上风电场高升压比DC/DC变换技术综述[J].电力系统保护与控制,2018,46(12):158-69.Guo Lingyu,Yao Gang,Zhou Lidan.Research review on high step-up ratio DC/DC converter for offshore DC wind farm[J].Power System Protection and Control,2018,46(12):158-69(in Chinese).
[8]Middlebrook R D,Cuk S.A general unified approach to modelling switching-converter power stages[C]//1976IEEE Power Electronics Specialists Conference.Cleveland,OH,USA:IEEE,1976:18-34.
[9]Krismer F,Kolar J W.Accurate small-signal model for the digital control of an automotive bidirectional dual active bridge[J].IEEE Transactions on Power Electronics,2009,24(12):2756-2768.
[10]Sanders S R,Noworolski J M,Liu X Z,et al.Generalized averaging method for power conversion circuits[J].IEEETransactions on Power Electronics1991,6(2):251-259.
[11]Caliskan V A,Verghese O C,Stankovic AM.Multi-frequency averaging of DC/DC converters[J].IEEETransactions on Power Electronics,1999,14(1):124-133.
[12]Qin Hengsi,Kimball J W.Generalized average modeling of dual active bridge DC-DC converter[J].IEEETransactions on Power Electronics,2012,27(4):2078-2084.
[13]Li Zhuoqiang,Wang Yue,Shi Ling,et al.Generalized averaging modeling and control strategy for three-phase dual-active-bridge DC-DC converters with three control variables[C]//2017 IEEE Applied Power Electronics Conference and Exposition(APEC).Tampa,FL,USA:IEEE,2017:1078-1084.
[14]Verghese G C,Elbuluk M E,Kassakian J G.A general approach to sampled-data modeling for power electronic circuits[J].IEEE Transactions on Power Electronics,1986,PE-1(2):76-89.
[15]Costinett D.Reduced order discrete time modeling of ZVS transition dynamics in the dual active bridge converter[C]//2015 IEEE Applied Power Electronics Conference and Exposition(APEC).Charlotte,NC,USA:IEEE,2015:365-370.
[16]Shi Ling,Lei Wanjun,Huang Jun,et al.Full discrete-time modeling and stability analysis of the digital controlled dual active bridge converter[C]//2016 IEEE 8th International Power Electronics and Motion Control Conference(IPEMC-ECCE Asia).Hefei,China:IEEE,2016:3813-3817.
[17]Costinett D,Zane R,Maksimovi?D.Discrete-time small-signal modeling of a 1 MHz efficiency-optimized dual active bridge converter with varying load[C]//2012IEEE 13th Workshop on Control and Modeling for Power Electronics(COMPEL).Kyoto,Japan:IEEE,2012:1-7.
[18]Alonso A R,Sebastian J,Lamar D G,et al.An overall study of a dual active bridge for bidirectional DC/DCconversion[C]//2010 IEEE Energy Conversion Congress and Exposition.Atlanta,GA,USA:IEEE,2010:1129-1135.
[19]Zhang Kai,Shan Zhenyu,Jatskevich J.Large-and small-signal average-value modeling of dual-active-bridge DC-DC converter considering power losses[J].IEEETransactions on Power Electronics,2017,32(3):1964-1974.
[20]黄珺,王跃,李卓强,等.基于三重移相控制的双主动全桥直流变换器优化调制策略[J].中国电机工程学报,2016,36(6):1658-1666.Huang Jun,Wang Yue,Li Zhuoqiang,et al.Optimized modulation scheme of dual active bridge DC-DCconverter based on triple-phase-shift control[J].Proceedings of the CSEE,2016,36(6):1658-1666(in Chinese).
[21]Zhang Fan,Ur Rehman M M,Zane R,et al.Improved steady-state model of the dual-active-bridge converter[C]//2015 IEEE Energy Conversion Congress and Exposition(ECCE).Montreal,QC,Canada:IEEE,2015:630-636.
[22]Mattavelli P,Spiazzi G,Tenti P.Predictive digital control of power factor preregulators with input voltage estimation using disturbance observers[J].IEEETransactions on Power Electronics,2005,20(1):140-147.
[23]Elaydi S.An introduction to difference equations[M].3rd ed.New York:Springer,2005.