光伏直流升压汇集系统的模型降阶启动控制策略
|
摘要
光伏直流升压汇集系统正常运行的前提是系统完成预充电,平稳建立直流母线电压。为了快速且更加稳定地完成该过程,该文研究了光伏直流升压汇集系统的拓扑结构和充电特点,在此基础上提出可控充电阶段电压外环采用比例(P)控制器可实现等效模型降阶,同时利用电容器对电流的积分作用来消除稳态误差。将其与多端模块化多电平换流器(modular multilevel converter,MMC)软启动中常用的电压外环比例积分(PI)控制进行了对比分析,结果表明,其降低了系统等效模型的阶次,且无需直流参考电压斜率控制器,有利于充电过程中系统的稳定及控制参数的选取。最后,通过MATLAB/Simulink仿真验证了所提控制策略的正确性和有效性。
The precondition for the normal operation of the PV system is to complete the pre-charge and establish DC bus voltage. To complete the process fast and more stably,the topological structure and charging characteristics of DC boost system for photovoltaic system are studied in this paper. On this basis,the paper proposes that the proportional controller can be used to reduce the order of the equivalent model in the controlled charging stage. At the same time,the steady-state error is eliminated by the integral action of the capacitor on the current. Compared to the proportion and integral control of the voltage outer loop used in the soft start of multi-terminal MMC,it reduces the order of the equivalent system model and does not need slope controller for DC reference voltage. It is beneficial to the system stability and the selection of control parameters during the charging process. Finally,the correctness and effectiveness of the proposed control strategy is verified by MATLAB/Simulink simulation.
The precondition for the normal operation of the PV system is to complete the pre-charge and establish DC bus voltage. To complete the process fast and more stably,the topological structure and charging characteristics of DC boost system for photovoltaic system are studied in this paper. On this basis,the paper proposes that the proportional controller can be used to reduce the order of the equivalent model in the controlled charging stage. At the same time,the steady-state error is eliminated by the integral action of the capacitor on the current. Compared to the proportion and integral control of the voltage outer loop used in the soft start of multi-terminal MMC,it reduces the order of the equivalent system model and does not need slope controller for DC reference voltage. It is beneficial to the system stability and the selection of control parameters during the charging process. Finally,the correctness and effectiveness of the proposed control strategy is verified by MATLAB/Simulink simulation.
引文
[1]丁若瑜,王毅,付媛,等.二极管钳位型MMC电路的均压控制策略[J].电力建设,2017,38(4):79-85.DING Ruoyu,WANG Yi,FU Yuan,et al. Voltage sharing control strategy of diode clamped M M C circuit[J]. Electric Pow er Construction,2017,38(4):79-85.
[2] WANG Y,HU C,DING R,et al. A nearest level PWM method for the M M C in DC distribution grids[J]. IEEE Transactions on Pow er Electronics,2018,33(11):9209-9218.
[3]姜雪松.隔离升压全桥DC-DC变换器拓扑理论和控制技术研究[D].北京:中国科学院研究生院(电工研究所),2006.JIANG Xuesong. Research on the topology theory and control technology of isolated boost full bride DC-DC converter[D].Beijing:Institute of Electrical Engineering,Chinese Academy of Sciences,2006.
[4]李永庆,孟伟.电动汽车预充电过程研究[J].汽车电器,2013(5):8-10.LI Yongqing,M ENG Wei. On the precharging process for EV[J].Auto Electric Parts,2013(5):8-10.
[5]曲平,李子欣,宋鹏先,等.隔离式双向全桥DC-DC变换器预充电研究[J].电工技术报,2014,29(S1):320-325.QU Ping,LI Zixin,SONG Pengxian,et al. Pre-charge strategy study for isolated dual active bridge DC-DC converter[J].Transactions of China Electrotechnical Society,2014,29(S1):320-325.
[6] XU Jianzhong,ZHAO Chengyong,ZHANG Baoshun,et al. New precharge and submodule capacitor voltage balancing topologies of modular multilevel converter for VSC-HVDC application[C]∥AsiaPacific Pow er and Energy Engineering Conference(APPEEC).2011:1-4.
[7]任涛,张杰,唐剑钊,等. MMC-HVDC模块电容器预充电策略及仿真分析[J].电力系统及其自动化学报,2013,25(5):144-148.REN Tao, ZHANG Jie, TANG Jianzhao, et al. M M C-HVDC charging strategy research and simulation analysis[J]. Proceedings of the CSU-EPSA,2013,25(5):144-148.
[8]王卫安,桂卫华,屠卿瑞,等.模块化多电平换流器型直流输电系统启动控制[J].大功率变流技术,2013(5):37-43.WANG Weian,GUI Weihua,TU Qingrui,et al. Startup control for M M C-HVDC system[J]. High Pow er Converter Technology,2013(5):37-43.
[9]孔明,邱宇峰,贺之渊,等.模块化多电平式柔性直流输电换流器的预充电控制策略[J].电网技术,2011,35(11):67-73.KONG M ing, QIU Yufeng, HE Zhiyuan, et al. Pre-charging control strategies of modular multilevel converter for VSC-HVDC[J]. Power System Technology,2011,35(11):67-73.
[10]周建,苏建徽,王新颖.模块化多电平换流器的预充电控制[J].高压电器,2014,50(4):103-107.ZHOU Jian,SU Jianhui,WANG Xinying. Pre-charging control of modular multilevel converter[J]. High Voltage Apparatus,2014,50(4):103-107.
[11]肖晃庆,徐政,薛英林,等.多端柔性直流输电系统的启动控制策略[J].高电压技术,2014,40(8):2550-2557.XIAO Huangqing,XU Zheng,XUE Yinglin,et al. Start control strategy of M M C-M TDC system[J]. High Voltage Engineering,2014,40(8):2550-2557.
[12]宋平岗,李云丰,王立娜,等. MMC-HVDC电容协同预充电控制策略[J].高电压技术,2014,40(8):2471-2477.SONG Pinggang, LI Yunfeng, WANG Lina, et al. Capacitor coordingating pre-charging control strategy of M M C-HVDC[J].High Voltage Engineering,2014,40(8):2471-2477.
[13]裘鹏,杨美娟,章姝俊,等. MMC-MTDC系统协调启动控制策略[J].电网技术,2015,39(7):1800-1807.QIU Penguin, YANG M eijuan, ZHANG Shujun, et al.Coordinated start-up strategy for M M C-M TDC system[J]. Pow er System Technology 2015,39(7):1800-1807.
[14] ZHANG Zhipeng, WANG Yibo. Simulation studies of DCconnected photovoltaic pow er system[C]//2017 IEEE Conference on Energy Internet and Energy System Integration. Beijing,China:IEEE,2017:1-6.
[15]陈海荣,张静,潘武略.电压源换流器型直流输电系统的启动控制[J].高电压技术,2009,35(5):1164-1169.CHEN Hairong,ZHANG Jing,PAN Wulue. Start-up control of VSC based on HVDC system[J]. High Voltage Engineering,2009,35(5):1164-1169.
[16]李政. PWM整流器阻抗特性研究[D].武汉:华中科技大学,2015.LI Zheng. Research on the impendence characteristics of PWM rectifier[D]. Wuhan:Huazhong University of Science and Technology,2015.
[17] TIAN Yanjun,LOH Poh Chiang,DENG Fujin,et al. DC-link voltage coordinated-proportional control for cascaded converter w ith zero steady-state error and reduced system type[J]. IEEE Transcations on Pow er Electronics,2016,31(4):3177-3188.
[18]阎发友,汤广福,孔明.基于模块化多电平换流器的直流电网预充电控制策略[J].中国电机工程学报,2015,35(20):5147-5154.YAN Fayou,TANG Guangfu,KONG M ing. Pre-charging control strategy for M M C-based DC grid[J]. Proceedings of the CSEE,2015,35(20):5147-5154.
[2] WANG Y,HU C,DING R,et al. A nearest level PWM method for the M M C in DC distribution grids[J]. IEEE Transactions on Pow er Electronics,2018,33(11):9209-9218.
[3]姜雪松.隔离升压全桥DC-DC变换器拓扑理论和控制技术研究[D].北京:中国科学院研究生院(电工研究所),2006.JIANG Xuesong. Research on the topology theory and control technology of isolated boost full bride DC-DC converter[D].Beijing:Institute of Electrical Engineering,Chinese Academy of Sciences,2006.
[4]李永庆,孟伟.电动汽车预充电过程研究[J].汽车电器,2013(5):8-10.LI Yongqing,M ENG Wei. On the precharging process for EV[J].Auto Electric Parts,2013(5):8-10.
[5]曲平,李子欣,宋鹏先,等.隔离式双向全桥DC-DC变换器预充电研究[J].电工技术报,2014,29(S1):320-325.QU Ping,LI Zixin,SONG Pengxian,et al. Pre-charge strategy study for isolated dual active bridge DC-DC converter[J].Transactions of China Electrotechnical Society,2014,29(S1):320-325.
[6] XU Jianzhong,ZHAO Chengyong,ZHANG Baoshun,et al. New precharge and submodule capacitor voltage balancing topologies of modular multilevel converter for VSC-HVDC application[C]∥AsiaPacific Pow er and Energy Engineering Conference(APPEEC).2011:1-4.
[7]任涛,张杰,唐剑钊,等. MMC-HVDC模块电容器预充电策略及仿真分析[J].电力系统及其自动化学报,2013,25(5):144-148.REN Tao, ZHANG Jie, TANG Jianzhao, et al. M M C-HVDC charging strategy research and simulation analysis[J]. Proceedings of the CSU-EPSA,2013,25(5):144-148.
[8]王卫安,桂卫华,屠卿瑞,等.模块化多电平换流器型直流输电系统启动控制[J].大功率变流技术,2013(5):37-43.WANG Weian,GUI Weihua,TU Qingrui,et al. Startup control for M M C-HVDC system[J]. High Pow er Converter Technology,2013(5):37-43.
[9]孔明,邱宇峰,贺之渊,等.模块化多电平式柔性直流输电换流器的预充电控制策略[J].电网技术,2011,35(11):67-73.KONG M ing, QIU Yufeng, HE Zhiyuan, et al. Pre-charging control strategies of modular multilevel converter for VSC-HVDC[J]. Power System Technology,2011,35(11):67-73.
[10]周建,苏建徽,王新颖.模块化多电平换流器的预充电控制[J].高压电器,2014,50(4):103-107.ZHOU Jian,SU Jianhui,WANG Xinying. Pre-charging control of modular multilevel converter[J]. High Voltage Apparatus,2014,50(4):103-107.
[11]肖晃庆,徐政,薛英林,等.多端柔性直流输电系统的启动控制策略[J].高电压技术,2014,40(8):2550-2557.XIAO Huangqing,XU Zheng,XUE Yinglin,et al. Start control strategy of M M C-M TDC system[J]. High Voltage Engineering,2014,40(8):2550-2557.
[12]宋平岗,李云丰,王立娜,等. MMC-HVDC电容协同预充电控制策略[J].高电压技术,2014,40(8):2471-2477.SONG Pinggang, LI Yunfeng, WANG Lina, et al. Capacitor coordingating pre-charging control strategy of M M C-HVDC[J].High Voltage Engineering,2014,40(8):2471-2477.
[13]裘鹏,杨美娟,章姝俊,等. MMC-MTDC系统协调启动控制策略[J].电网技术,2015,39(7):1800-1807.QIU Penguin, YANG M eijuan, ZHANG Shujun, et al.Coordinated start-up strategy for M M C-M TDC system[J]. Pow er System Technology 2015,39(7):1800-1807.
[14] ZHANG Zhipeng, WANG Yibo. Simulation studies of DCconnected photovoltaic pow er system[C]//2017 IEEE Conference on Energy Internet and Energy System Integration. Beijing,China:IEEE,2017:1-6.
[15]陈海荣,张静,潘武略.电压源换流器型直流输电系统的启动控制[J].高电压技术,2009,35(5):1164-1169.CHEN Hairong,ZHANG Jing,PAN Wulue. Start-up control of VSC based on HVDC system[J]. High Voltage Engineering,2009,35(5):1164-1169.
[16]李政. PWM整流器阻抗特性研究[D].武汉:华中科技大学,2015.LI Zheng. Research on the impendence characteristics of PWM rectifier[D]. Wuhan:Huazhong University of Science and Technology,2015.
[17] TIAN Yanjun,LOH Poh Chiang,DENG Fujin,et al. DC-link voltage coordinated-proportional control for cascaded converter w ith zero steady-state error and reduced system type[J]. IEEE Transcations on Pow er Electronics,2016,31(4):3177-3188.
[18]阎发友,汤广福,孔明.基于模块化多电平换流器的直流电网预充电控制策略[J].中国电机工程学报,2015,35(20):5147-5154.YAN Fayou,TANG Guangfu,KONG M ing. Pre-charging control strategy for M M C-based DC grid[J]. Proceedings of the CSEE,2015,35(20):5147-5154.