Abstract：In this paper, an optimal control strategy was proposed according to the problems of the full-bridge three level (FBTL) DC-DC converter, such as coordinated control of two duty cycles, small output power of the FBTL DC-DC converter and voltage balance of divided capacitors. First, the characteristics of the FBTL DC-DC converter was analyzed in detail and a self-balance modulation scheme for divided capacitor voltage was investigated. Second, a strategy to resist the voltage disturbance of the divided capacitor was proposed. At the same time, a restraint condition for the duty cycles was investigated. Third, taking the harmonics of the transformer input voltage as the objective, and taking the power of the FBTL DC-DC converter and the voltage regulation capacity of the divided capacitor as the constraints, an optimization model for the duty cycles was established. The optimal duty cycles were calculated offline and stored in the digital control system. The look-up table method was adopted to get the optimal duty cycles. The proposed method does not require an accurate model of the converter, and the control process is simple and efficient. Finally, a FBTL DC-DC converter model in Matlab/Simuink and a FBTL DC-DC converter experimental prototype were built to verify the theoretical analysis.
李伟, 王辉, 黄守道, 吴轩. 全桥三电平DC-DC变换器优化控制策略[J]. 电工技术学报, 2021, 36(16): 3342-3353.
Li Wei, Wang Hui, Huang Shoudao, Wu Xuan. Optimal Control for the Full-Bridge Three-Level DC-DC Converter. Transactions of China Electrotechnical Society, 2021, 36(16): 3342-3353.
[1] 张亚超, 黄张浩, 郑峰, 等. 基于风电出力模糊集的电-气耦合系统分布鲁棒优化调度[J]. 电力系统自动化, 2020, 44(4): 44-53. Zhang Yachao, Huang Zhanghao, Zheng Feng, et al.Distributionally robust optimal dispatch for power- gas coupled system based on fuzzy set of wind power output[J]. Automation of Electric Power Systems, 2020, 44(4): 44-53. [2] Dong Huanfeng, Xu Zheng, Song Pengcheng, et al.Optimized power redistribution of offshore wind farms integrated VSC-MTDC transmissions after onshore converter outage[J]. IEEE Transactions on Industrial Electronics, 2017, 64(11): 8948-8958. [3] 王新颖, 汤广福, 贺之渊, 等. 远海风电场直流汇集用 DC-DC 变换器拓扑研究[J]. 中国电机工程学报, 2017, 37(3): 837-847. Wang Xinying, Tang Guangfu, He Zhiyuan, et al.Topology research of DC-DC converters for offshore wind farm DC collection systems[J]. Proceedings of the CSEE, 2017, 37(3): 837-847. [4] 魏晓光, 王新颖, 高冲, 等. 用于直流电网的高压大容量 DC-DC 变换器拓扑研究[J]. 中国电机工程学报, 2014, 34(20): 218-224. Wei Xiaoguang, Wang Xinying, Gao Chong, et al.Topologies research of high voltage and high-power DC-DC converters used in DC grids[J]. Proceedings of the CSEE, 2014, 34(20): 218-224. [5] Juan David Páez, David Frey, Jose Maneiro, et al.Overview of DC-DC converters dedicated to HVDC grids[J]. IEEE Transactions on Power Delivery, 2019, 34(1): 119-128. [6] 鲁静, 同向前, 张嘉翔, 等. L-LLC谐振型双向DC-DC变换器的复合最优轨迹控制策略研究[J]. 电工技术学报, 2020, 35(增刊1): 60-69. Lu Jing, Tong Xiangqian, Zhang Jiaxiang, et al.Research on the hybrid optimal control principle based on the L-LLC resonant bidirectional DC-DC converter[J]. Transactions of China Electrotechnical Society, 2020, 35(S1): 60-69. [7] 杨惠, 晁凯悦, 孙向东, 等. 基于矢量作用时间的双向DC-DC变换器预测电流控制方法[J]. 电工技术学报, 2020, 35(增刊1): 70-80. Yang Hui, Yao Kaiyue, Sun Xiangdong, et al.Predictive current control method for bidirectional DC-DC converter based on optimal operating time of vector[J]. Transactions of China Electrotechnical Society, 2020, 35(S1): 70-80. [8] 何圣仲, 代东雷. 开关变换器数字双功率控制技术[J]. 电机与控制学报, 2020, 24(3): 38-44. He Shengzhong, Dai Donglei.Digital bi-power control technique for switching converters[J]. Electric Machines and Control, 2020, 24(3): 38-44. [9] 王强, 单瑞香, 王天施, 等. 单相全桥谐振直流环节软开关逆变器[J]. 电机与控制学报, 2017, 21(3): 38-47. Wang Qiang, Shan Ruixiang, Wang Tianshi, et al.Single-phase full-bridge resonant DC-link soft-switching inverter[J]. Electric Machines and Control, 2017, 21(3): 38-47. [10] 张洪寅, 童朝南, 王泽庭, 等. 基于临界模态的DCM-LCC谐振变换器的归一化分析与设计[J]. 电工技术学报, 2019, 34(1): 103-115. Zhang Hongyin, Tong Chaonan, Wang Zeting, et al.Normalized analysis and design of DCM-LCC resonant converter based on critical current mode[J]. Transactions of China Electrotechnical Society, 2019, 34(1): 103-115. [11] 阮新波, 严仰光. 软开关PWM三电平直流变换器[J]. 电工技术学报, 2000, 15(6): 24-34. Ruan Xinbo, Yan Yangguang.Soft-switching PWM three-level converters[J]. Transactions of China Electrotechnical Society, 2000, 15(6): 24-34. [12] 陈志英, 阮新波. 零电压开关PWM复合式全桥三电平变换器[J]. 中国电机工程学报, 2004, 24(5): 24-29. Chen Zhiying, Ruan Xinbo.Zero-voltage-switching PWM hybrid full-bridge three-level converter[J]. Proceedings of the CSEE, 2004, 24(5): 24-29. [13] 宋文胜, 冯晓云. 一种单相空间矢量脉宽调制优化方法[J]. 电工技术学报, 2011, 26(4): 107-113. Song Wensheng, Feng Xiaoyun.A single phase SVPWM optimized method[J]. Transactions of China Electrotechnical Society, 2011, 26(4): 107-113. [14] 刘计龙, 肖飞, 陈伟, 等. 一种多电平全桥直流变换器新型控制策略研究[J]. 中国电机工程学报, 2014, 34(33): 5854-5860. Liu Jilong, Xiao Fei, Chen Wei, et al.Research on a novel control scheme for three-level full-bridge converter[J]. Proceedings of the CSEE, 2014, 34(33): 5854-5860. [15] Deng Fujin, Chen Zhe.Control of improved full- bridge three-level DC-DC converter for wind turbines in a DC grid[J]. IEEE Transactions on Power Electronics, 2013, 28(1): 314-324. [16] Liu Peng, Duan Shanxu.Analysis of the neutral-point voltage self-balance mechanism in the three-level full-bridge DC-DC converter by introduction of flying capacitors[J]. IEEE Transactions on Power Electro- nics, 2019, 34(12): 11736-11747. [17] 刘朋, 陈昌松, 段善旭, 等. 带飞跨电容的三电平全桥直流变换器输入中点电压的自平衡分析[J]. 电工技术学报, 2018, 33(18): 4335-4344. Liu Peng, Chen Changsong, Duan Shanxu, et al.Self-balance mechanism analysis of the neutral point voltage in three-level full bridge DC-DC converter with flying capacitors[J]. Transactions of China Electrotechnical Society, 2018, 33(18): 4335-4344. [18] Yang Guorun, Xiao Fei, Fan Xuexin, et al.Three- phase three-level phase-shifted PWM DC-DC converter for electric ship MVDC application[J]. IEEE Transactions on Power Electronics, 2017, 5(1): 162-170. [19] 杨国润, 肖飞, 范学鑫, 等. 中压大容量三重化三电平直流变换器冗余容错控制[J]. 电工技术学报, 2017, 32(1): 186-195. Yang Guorun, Xiao Fei, Fan Xuexin, et al.Redundant and fault tolerant control of a medium-voltage high- power three-phase three-level DC-DC converter[J]. Transactions of China Electrotechnical Society, 2017, 32(1): 186-195. [20] 杨国润, 肖飞, 范学鑫, 等. 一种四管动作的高压大功率三电平变流器双脉冲测试方法[J]. 中国电机工程学报, 2015, 35(3): 695-701. Yang Guorun, Xiao Fei, Fan Xuexin, et al.A novel four-switch action double-pulse test method for high-voltage high-power three-level converters[J]. Proceedings of the CSEE, 2015, 35(3): 695-701. [21] 刘成君, 杨仁刚. 变压器谐波损耗的计算与分析[J].电力系统保护与控制, 2008, 36(13): 33-36. Liu Chengjun, Yang Rengang.Calculation and analysis of transformer’s harmonic loss[J]. Power System Protection and Control, 2008, 36(13): 33-36. [22] Liu Peng, Chen Changsong, Duan Shanxu, et al.An optimized modulation strategy for the three-level DAB converter with five control degrees of free- dom[J]. IEEE Transactions on Industrial Electronics, 2020, 67(1): 254-264. [23] Chen Wu, Ruan Xinbo, Yan Hong, et al.DC-DC conversion systems consisting of multiple converter modules: stability, control, and experimental verifi- cations[J]. IEEE Transactions on Power Electronics, 2009, 24(6): 1463-1474. [24] 石季英, 凌乐陶, 薛飞, 等. 领地粒子群算法在光伏最大功率跟踪的应用[J]. 太阳能学报, 2019, 40(9): 2554-2559. Shi Jiying, Ling Yuetao, Xue Fei, et al.Application of territorial PSO in global MPPT for PV array[J]. Acta Energiae Solaris Sinica, 2019, 40(9): 2554-2559. [25] Wu Jiangling, Sun Xiaodong.Accurate torque modeling with PSO-based recursive robust LSSVR for a segmented-rotor switched reluctance motor[J]. CES Transactions on Electrical Machines and Systems, 2020, 4(2): 96-104. [26] 张弛, 曾杰, 曾嵘, 等. 应用于储能系统的双向DC-DC效率模型研究[J]. 电气传动, 2019, 49(8): 38-42. Zhang Chi, Zeng Jie, Zeng Rong, et al.Research on efficiency model of bidirectional DC-DC applied to energy storage system[J]. Electric Drive, 2019, 49(8): 38-42. [27] 李国栋, 李培, 徐永海, 等. 变压器谐波损耗计算方法比较与仿真[J]. 电力系统保护与控制, 2010, 38(18): 63-68. Liu Guodong, Li Pei, Xu Yonghai, et al.Comparison and simulation of calculation methods for transformer harmonic losses[J]. Power System Protection and Control, 2010, 38(18): 63-68. [28] 唐海燕, 李建泉. DC-DC 变换器中25kW高频功率变压器的设计[J]. 大功率变流技术, 2010, 2(5): 26-30. Tang Haiyan, Li Jianquan.Design of 25kW high frequency power transformer for DC-DC converter[J]. High Power Converter Technology, 2010, 2(5): 26-30. [29] 汤厚涛. DC-DC充电机功率损耗分析及电路设计[D]. 成都: 电子科技大学, 2016. [30] 李琼林, 邹磊, 刘会金, 等. 电力变压器谐波损耗仿真计算与实验研究[J]. 电网技术, 2013, 37(12): 3521-3527. Li Qionglin, Zou Lei, Liu Huijin, et al.Simulation calculation and experimental research on harmonic losses in power transformers[J]. Power System Technology, 2013, 37(12): 3521-3527. [31] 贺威. 电力电子变压器 DC-DC变换器的设计[D]. 徐州: 中国矿业大学, 2016. [32] 郭云翔. 大功率中频变压器特性研究与优化设计[D]. 保定: 华北电力大学, 2017. [33] 王瑞田, 赵治华, 肖飞, 等. 中频变压器并联绕组环流的频率特性及其对等效电阻的影响分析[J]. 电工技术学报, 2020, 35(1): 251-258. Wang Ruitian, Zhao Zhihua, Xiao Fei, et al.Investigation of frequency characteristics and effect on winding equivalent resistance of circulating current in medium-frequency transformer[J]. Transa- ctions of China Electrotechnical Society, 2020, 35(1): 251-258. [34] 黄佩. 大功率中频变压器电磁分析与优化设计[D]. 武汉: 华中科技大学, 2018.
2021, Vol. 36 
