三端口CLLC固态变压器的设计与优化

doi:10.19595/j.cnki.1000-6753.tces.231875

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Abstract The three-port CLLC solid-state transformer (TP-CLLC-SST) consists of input and output capacitors, a full-bridge circuit, a distributed resonant tank, and a three-winding high-frequency transformer. The converter can be operated open-loop at a fixed switching frequency and close to 50% duty cycle. When the switching frequency is close to the resonant frequency, the LLC series resonant structure is commonly used in three-port solid-state transformers due to its many advantages such as soft switching over the full load range, inherent load regulation characteristics, high power density, high efficiency, and the ability to achieve open-loop operation. The TP-CLLC-SST can be applied in a DC microgrid system containing multiple renewable energy generation systems (RESs), energy storage systems (ESSs), and AC or DC loads to achieve efficient integration and control of RESs, ESSs, loads and the grid.
The existing literature on the design method of resonant parameters for distributed resonant tanks of the TP-CLLC-SST is complex and unclear, the impedance matching degree of distributed resonant tanks is not high, and the dead time and magnetizing inductance of the converter in various operating modes has not been optimized. In order to solve the problems of determining the resonant parameters, the impedance matching of distributed resonant tanks and the optimization of dead time and magnetizing inductance, this paper proposes an optimized design method for the TP-CLLC-SST applied in a DC microgrid system.
Firstly, the impedance matching and resonant parameter determination method of distributed resonant tanks is proposed in this paper. First, establish the equivalent characteristic circuit of the distributed resonant tanks of TP-CLLC-SST. Then, sequentially calculate the characteristic impedance of each port to one port, and calculate the equivalent characteristic impedance of each port. Finally, make the equivalent characteristic impedance of each port equal to obtain the characteristic impedance and resonant inductance relationship of each port. This method simplifies the impedance matching and resonant parameter design process. The maximum port voltage offset of the converter was reduced from 5.6% to 1.02%, thus enhancing the load regulation characteristics of the converter and reducing the port voltage change rate. Secondly, the RMS of the distributed resonant tank input and output currents of the TP-CLLC-SST under different operating modes and load conditions are derived. Moreover, the optimized selection method of dead time and magnetizing inductance of TP-CLLC-SST is given by combining the input current RMS equations of resonant tank, i.e., to find out the range of dead time corresponding to smaller RMS input current of resonant tank in each operation mode, and take the intersection of these optimized dead time ranges to get the optimal dead time and magnetizing inductance of the converter in three operation modes. In the experimental prototype constructed with three port voltages of 100 V, 400 V and 600 V and a power of 1 kW, the optimal dead time determined by this way enables the converter to achieve an average efficiency of 98.15% at full load and a peak efficiency of 98.3%, which improves the operating efficiency of the converter in the three operation modes.

Key words： Multi-port solid-state transformer distributed resonant tanks impedance matching CLLC series resonant soft switching

Received: 08 November 2023

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TM46

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	Zhao Jian
	Zhang Zhe
	Li Zhaoduan
	Song Weibo

Cite this article:

Zhao Jian,Zhang Zhe,Li Zhaoduan等. Design and Optimization of Three-Port CLLC Solid-State Transformer[J]. Transactions of China Electrotechnical Society, 2024, 39(23): 7542-7553.

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https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.231875 OR https://dgjsxb.ces-transaction.com/EN/Y2024/V39/I23/7542

[1] 廖志贤, 李彬彬, 索之闻, 等. 磁集成三端口电力电子变压器的改进控制方法[J].电力系统自动化, 2023, 47(11): 133-143.
Liao Zhixian, LiBinbin, SuoZhiwen, et al. Improved control method for three-port power electronic transformer based on magnetic integration[J]. Automation of Electric Power Systems, 2023, 47(11): 133-143.
[2] 万家伟, 陈汉超, 廖承, 等. 用于智能电网含电力电子变换器的混合型变压器设计[J/OL]. 电源学报2022: 1-9[2024-08-05].
WanJiawei, ChenHanchao, Liao Cheng,et al. Hybrid high voltage transformer design with power electronic converter for smart grid[J/OL]. Journal of Power Supply, 2022: 1-9[2024-08-05].
[3] 刘基业, 郑泽东, 李驰,等. 基于准串联SiC MOSFET的高增益直流电力电子变压器[J]. 中国电机工程学报, 2022, 42(8): 2987-2996.
Liu Jiye, Zheng Zedong, Li Chi, et al.A high voltage-gain DC power electronic transformer based on quasi-series-connected SiC MOSFET[J]. Proceedings of the CSEE, 2022, 42(8): 2987-2996.
[4] 赵聪, 胡钰杰, 胡洋, 等. 间接矩阵谐振型电力电子变压器高频环节特性分析与开关频率设计方法[J/OL]. 中国电机工程学报, 2024: 1-10[2024-08-06].
ZhaoCong, Hu Yujie, Hu Yang, et al. High-frequency-link characteristics analysis and switching frequency design method of an indirect matrix resonant type power electronic transformer[J/OL]. Proceedings of the CSEE, 2024: 1-10[2024-08-06].
[5] 王武, 雷文浩, 蔡逢煌,等. 结合电流应力优化的双有源全桥DC-DC变换器自抗扰控制[J]. 电工技术学报, 2022, 37(12): 3073-3086.
Wang Wu, Lei Wenhao, Cai Fenghuang, et al.Active disturbance rejection control of dual-active-bridge DC-DC converter with current stress optimization[J]. Transactions of China Electrotechnical Society, 2022, 37(12): 3073-3086.
[6] 江凌峰, 龚邻骁, 金新宇, 等. 基于遗传算法的多模块IPOP双有源全桥DC-DC变换器总电流有效值优化策略[J]. 电工技术学报, 2023, 38(24): 6782-6797.
Jiang Lingfeng, Gong Linxiao, Jin Xinyu, et al.Total root mean square current optimization of IPOP dual active bridge DC-DC converter based on genetic algorithm[J]. Transactions of China Electrotechnical Society, 2023, 38(24): 6782-6797.
[7] 李加明, 任小永, 周治成,等. 基于谐振网络优化的双向LLC-DCX多模块并联系统均流优化研究[J]. 电工技术学报, 2023, 38(10): 2720-2730, 2756.
Li Jiaming, Ren Xiaoyong, Zhou Zhicheng, et al.Research on current sharing optimization of bidirectional LLC-DCX multi-module parallel system based on resonant network optimization[J]. Transactions of China Electrotechnical Society, 2023, 38(10): 2720-2730, 2756.
[8] 杨勇, 宋大威, 顾占彪,等. 星载1 MHz GaN LLC变换器低反向导通损耗控制[J]. 电工技术学报, 2022, 37(24): 6183-6190.
Yang Yong, Song Dawei, Gu Zhanbiao, et al.Low reverse conduction loss control for 1 MHz GaN-based LLC converter used in satellite application[J]. Transactions of China Electrotechnical Society, 2022, 37(24): 6183-6190.
[9] Zhao Biao, Song Qiang, Li Jianguo, et al.Modular multilevel high-frequency-link DC transformer based on dual active phase-shift principle for medium-voltage DC power distribution application[J]. IEEE Transactions on Power Electronics, 2017, 32(3): 1779-1791.
[10] Khanzadeh B, Serdyuk Y, Thiringer T.Evaluation of core losses in transformers for three-phase multi-level DAB converters[C]//2022 24th European Conference on Power Electronics and Applications (EPE'22 ECCE Europe), Hanover, Germany, 2022: 1-11.
[11] 程启明, 陈颖, 孙英豪, 等.电网电压不平衡下MMC-SST反馈线性化滑模控制策略[J]. 南方电网技术, 2024, 18(3): 129-137.
Cheng Qiming, Chen Ying, Sun Yinghao, et al.Feedback linearization sliding-mode control strategy for MMC-SST under unbalanced power grid voltage[J]. Southern Power System Technology, 2024, 18(3): 129-137.
[12] 刘子薇, 孙兆龙, 刘宝龙,等. 基于直接功率控制的双有源桥暂态直流偏置抑制策略[J]. 电工技术学报, 2023, 38(12): 3234-3247.
Liu Ziwei, Sun Zhaolong, Liu Baolong, et al.Transient DC bias suppression strategy of dual active bridge based on direct power control[J]. Transactions of China Electrotechnical Society, 2023, 38(12): 3234-3247.
[13] 康薇, 肖飞, 任强,等. 双有源桥DC-DC变换器三移相调制及其死区效应分析和补偿[J]. 电工技术学报, 2024, 39(6): 1907-1922.
Kang Wei, Xiao Fei, Ren Qiang, et al.Three-phase-shift modulation and its dead band effect analysis and compensation of dual-active-bridge DC-DC converter[J]. Transactions of China Electrotechnical Society, 2024, 39(6): 1907-1922.
[14] 刘文强, 刘春喜, 蔡金汕. 基于动态矩阵控制的混合三电平双有源桥变换器回流功率优化[J/OL]. 电气工程学报, 2024: 1-10[2024-08-06].
Liu Wengqiang, Liu Chunxi, Ca Jinshan, et al. Optimization of backflow power of hybrid three-level dual active bridge converter based on dynamic matrix control[J/OL]. Journal of Electrical Engineering, 2024: 1-10[2024-08-06].
[15] 赖纪东, 姚娴, 苏建徽, 等. 死区影响下双有源桥DC-DC变换器的改进型协同三移相控制[J].高电压术, 2023, 49(11): 4827-4838.
LaiJidong, Yao Xian,Su Jianhui, et al. Improved CTPS control for dual active bridge DC-DC converter under dead time influence[J].High Voltage Engineering, 2023, 49(11): 4827-4838.
[16] 高宇, 李若愚, 李林柘,等. 三重移相调制模式下双有源变换器的直接功率控制[J]. 电工技术学报, 2022, 37(18): 4707-4719.
Gao Yu, Li Ruoyu, Li Linzhe, et al.Triple phase shift modulation-based direct power control strategy for a dual active bridge converter[J]. Transactions of China Electrotechnical Society, 2022, 37(18): 4707-4719.
[17] 杨康诣, 陈帝发, 陈艳慧. 双有源桥直流变换器三移相下回流功率和电感电流峰值优化策略[J/OL].电源学报, 2023: 1-10[2024-08-06].
Yang Kangyi, Chen Difa, Chao, Chen Yanhui. Back-flow power and inductance peak current optimization strategy of dual-acvtive-bridge DC/DC converter with triple-phase-shift[J]. Journal of Power Supply, 2023: 1-10[2024-08-06].
[18] 曾进辉, 饶尧, 兰征, 等. 三重移相控制的DAB变换器多目标统一优化控制策略[J]. 电源学报, 2024, 22(5): 74-85.
ZengJinhui, RaoYao, LanZheng, et al. Multi-objective unified optimal control strategy for DAB converter with triple-phase-shift control[J]. Journal of Power Supply, 2024, 22(5): 74-85.
[19] Tran Y K, Dujić D, Barrade P.Multiport resonant DC-DC converter[C]//IECON 2015-41st Annual Conference of the IEEE Industrial Electronics Society, Yokohama, Japan, 2015: 3839-3844.
[20] Tomas-Manez K, Zhang Zhe, Ouyang Ziwei.Unregulated series resonant converter for interlinking DC nanogrids[C]//2017 IEEE 12th International Conference on Power Electronics and Drive Systems (PEDS), Honolulu, HI, USA, 2017: 647-654.
[21] Tomas-Manez K, Zhang Zhe, Ouyang Ziwei.Multi-port isolated LLC resonant converter for distributed energy generation with energy storage[C]//2017 IEEE Energy Conversion Congress and Exposition (ECCE), Cincinnati, OH, USA, 2017: 2219-2226.
[22] Lee I O, Moon G W.The k-Q analysis for an LLC series resonant converter[J]. IEEE Transactions on Power Electronics, 2014, 29(1): 13-16.
[23] Manez K T, Zhang Zhe, Xiao Yudi.Three-port series-resonant converter DC transformer with integrated magnetics for high efficiency operation[C]//2018 IEEE Energy Conversion Congress and Exposition (ECCE), Portland, OR, USA, 2018: 5622-5629.