基于相位补偿的直流配电系统频振荡抑制策略

doi:10.19595/j.cnki.1000-6753.tces.241488

摘要
图/表
参考文献
相关文章 (15)

全文: PDF (1361 KB)
输出: BibTeX | EndNote (RIS)

摘要

直流配电系统中电力电子设备分布集中,总体呈现弱阻尼特性,易引发一系列小信号稳定性问题,随着AI集群计算等供电需求的大幅增长,供电密度相应提升,使得阻抗不匹配点逐渐向高频段移动,尤其是数字控制延时所导致的高频振荡问题逐渐凸显。针对此问题,本文提出一种基于相位补偿器的直流配电系统高频振荡抑制策略,首先考虑了系统中的数字控制延时,构建级联直流系统的修正阻抗小信号模型,提升高频段建模结果的准确性;其次,基于修正模型,对配电系统进行了高频振荡机理的分析;最后,考虑高频振荡的主要影响因素,提出了相位补偿器策略,通过修改系统的控制回路重塑负载变换器的闭环输入阻抗,对直流配电系统中的高频振荡进行有效抑制,提升系统的供电稳定性。在240V直流配电系统中对该方法进行了测试,实验结果验证了系统稳定性分析结果的正确性以及相位补偿策略的性能。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	王彤鹭
	王跃
	樊囿麟
	李宇飞
	赵笔安

关键词 ：相位补偿, 直流配电系统, 高频振荡, 小信号稳定性, 数字控制

Abstract：

With the access of a large number of distributed power supplies and various types of DC loads, the distribution of power electronic equipment in the DC distribution system becomes more concentrated, leading to the inertia and damping of the system being reduced, which makes it easy that small-signal stability problems occur, divided into low-frequency oscillation and high-frequency oscillation. Among them, the problem of low-frequency oscillation caused by the negative impedance characteristic of constant power load has been concerned and solved widely. However, with the substantial growth of power supply demand of AI cluster computing and so on, the system power supply density requirements are increased correspondingly, so the input capacitance of the converter is reduced constantly, making the impedance mismatch point move to the high-frequency band gradually. Because the digital control is flexible and reliable, it is often used for the control of converters, which makes the high-frequency oscillation problem become more and more prominent. Therefore, in order to promote the improvement of the next generation of high-density and high-efficiency power supply, the high-frequency oscillation problem in the DC distribution system needs to be solved.
To solve this issue, the mechanism of high-frequency oscillation in DC distribution system was analyzed. Firstly, considering the influence of each link in the digital control loop of the actual system, the modified small- signal model of the load converter impedance was constructed, making the accuracy range of the model be extended to the kHz level. Secondly, based on the modified model, the stability problem of DC distribution system was further analyzed, and the classification of low-frequency oscillation and high-frequency oscillation of small-signal oscillation problem was proposed, and the main factors of high-frequency oscillation problem were analyzed. The digital control delay includes control delay and voltage and current sampling delay, in which the calculation delay is the main factor affecting the stability of the system, the current loop sampling delay is the second, and the voltage loop sampling delay can be negligible.
A phase compensation-based high-frequency oscillation suppression method was proposed for DC power distribution system. Firstly, the phase compensator was added to the control loop to compensate the dominant factor of high-frequency oscillation in DC distribution system. Secondly, the compensator parameters were designed to compensate the phase of the system in the high-frequency band and improve the stability of the system, so as to solve the high-frequency oscillation problem in the DC distribution system. Finally, the influence of the added strategy on the stability and dynamic performance of the system was analyzed theoretically.
The experimental results based on 3kW, 240-400V experimental platform validated the correctness of the stability analysis results and the performance of the phase compensation strategy. The results show that the proposed small-signal model of modified impedance converter can reflect the digital control link in the actual system, and ensure the accuracy of the system modeling in high-frequency band. At the same time, the proposed phase compensation strategy can improve the small-signal stability of DC distribution system, solve the problem of high-frequency oscillation of cascaded DC system, and ensure the excellent dynamic performance of the system. In addition, when the load power, input voltage, switching frequency or equivalent inductance of the cable changes, the proposed control strategy can ensure good stability and robustness of the system.

Key words： Phase compensation DC distribution power system high-frequency oscillation small-signal stability digital control

收稿日期: 2024-08-23

PACS:	TM721.1
	TM712

通讯作者: 王跃, 男,1972年生,教授,博士生导师,研究方向为新能源变流器控制与稳定性分析、柔性直流输电等。E-mail：davidwangyue@mail.xjtu.edu.cn

作者简介: 王彤鹭, 女,2000年生,硕士研究生,研究方向为直流配电系统的阻抗建模、控制及稳定性分析。E-mail：tlwang@stu.xjtu.edu.cn

引用本文:

王彤鹭, 王跃, 樊囿麟, 李宇飞, 赵笔安. 基于相位补偿的直流配电系统频振荡抑制策略[J]. 电工技术学报, 0, (): 1488-9. Wang Tonglu, Wang Yue, Fan Youlin, Li Yufei, Zhao Bi'an. A Phase Compensation-Based High-Frequency Oscillation Suppression Method for DC Power Distribution Systems. Transactions of China Electrotechnical Society, 0, (): 1488-9.

链接本文:

https://dgjsxb.ces-transaction.com/CN/10.19595/j.cnki.1000-6753.tces.241488 https://dgjsxb.ces-transaction.com/CN/Y0/V/I/1488

[1] 张泽华, 宋桂英, 张晓璐, 等. 考虑恒功率负载的直流微电网稳定性与鲁棒性控制策略[J]. 电工技术学报, 2023, 38(16): 4391-4405.
Zhang Zehua, Song Guiying, Zhang Xiaolu, et al.Stability and robustness control strategy of DC microgrid considering constant power load[J]. Transactions of China Electrotechnical Society, 2023, 38(16): 4391-4405.
[2] 刘笑, 杨建, 李力, 等. 基于机器学习的带被动阻尼直流微电网系统的稳定性检测[J]. 电工技术学报, 2024, 39(8): 2281-2293, 2324.
Liu Xiao, Yang Jian, Li Li, et al.Stability detection of DC microgrid systems with passive damping based on machine learning[J]. Transactions of China Electrotechnical Society, 2024, 39(8): 2281-2293, 2324.
[3] 李霞林, 郭力, 王成山, 等. 直流微电网关键技术研究综述[J]. 中国电机工程学报, 2016, 36(1): 2-17.
Li Xialin, Guo Li, Wang Chengshan, et al.Key technologies of DC microgrids: an overview[J]. Proceedings of the CSEE, 2016, 36(1): 2-17.
[4] 王晴, 刘增, 韩鹏程, 等. 基于变流器输出阻抗的直流微电网下垂并联系统振荡机理与稳定边界分析[J]. 电工技术学报, 2023, 38(8): 2148-2161.
Wang Qing, Liu Zeng, Han Pengcheng, et al.Analysis of oscillation mechanism and stability boundary of droop-controlled parallel converters based on output impedances of individual converters in DC microgrids[J]. Transactions of China Electrotechnical Society, 2023, 38(8): 2148-2161.
[5] 吴翔宇, 张晓红, 尚子轩, 等. 基于频域阻抗网络建模分析的交直流微电网振荡问题研究[J]. 电工技术学报, 2024, 39(8): 2294-2310.
Wu Xiangyu, Zhang Xiaohong, Shang Zixuan, et al.Research on the oscillation problem of AC-DC microgrids based on frequency domain impedance network modeling and analysis[J]. Transactions of China Electrotechnical Society, 2024, 39(8): 2294-2310.
[6] 李周, 王宇涵, 顾伟, 等. 直流电网及其运行控制策略发展趋势[J/OL]. 电力系统自动化, 2024 (2024-08-07). https://kns.cnki.net/kcms/detail/32.1180.TP.20240806.1914.004.html.
Li Zhou, Wang Yuhan, Gu Wei, et al. Development trend of DC power grid and its operation and control strategy [J/OL]. Automation of Electric Power Systems, 2024 (2024-08-07). https://kns.cnki.net/kcms/detail/32.1180.TP.20240806.1914.004.html.
[7] 郑凯元, 杜文娟, 王海风. 聚合恒功率负荷对直流微电网稳定性影响的阻抗法分析[J]. 电网技术, 2021, 45(1): 134-148.
Zheng Kaiyuan, Du Wenjuan, Wang Haifeng.DC microgrid StabilityAffected by aggregated constant power loads based on impedance method[J]. Power System Technology, 2021, 45(1): 134-148.
[8] 庄莹, 裴玮, 刘子奇, 等. 提升低压直流配电稳定性的时滞模型预测附加控制[J]. 电工技术学报, 2023, 38(12): 3248-3263.
Zhuang Ying, Pei Wei, Liu Ziqi, et al.Time-delay model predictive additional control strategy to improve the stability of low-voltage DC distribution system[J]. Transactions of China Electrotechnical Society, 2023, 38(12): 3248-3263.
[9] 杜韦静, 张军明, 钱照明. Buck变流器级联系统直流母线电压补偿控制策略[J]. 电工技术学报, 2015, 30(1): 135-142.
Du Weijing, Zhang Junming, Qian Zhaoming.Compensation methodology for DC bus voltage of cascaded system formed by buck converters[J]. Transactions of China Electrotechnical Society, 2015, 30(1): 135-142.
[10] Cespedes M, Xing Lei, Sun Jian.Constant-power load system stabilization by passive damping[J]. IEEE Transactions on Power Electronics, 2011, 26(7): 1832-1836.
[11] 王成山, 李微, 王议锋, 等. 直流微电网母线电压波动分类及抑制方法综述[J]. 中国电机工程学报, 2017, 37(1): 84-98.
Wang Chengshan, Li Wei, Wang Yifeng, et al.DC bus voltage fluctuation classification and restraint methods review for DC microgrid[J]. Proceedings of the CSEE, 2017, 37(1): 84-98.
[12] Zhang Xin, Ruan Xinbo, Zhong Qingchang.Improving the stability of cascaded DC/DC converter systems via shaping the input impedance of the load converter with a parallel or series virtual impedance[J]. IEEE Transactions on Industrial Electronics, 2015, 62(12): 7499-7512.
[13] He Bangbang, Chen Wu, Li Xin, et al.A power adaptive impedance reshaping strategy for cascaded DC system with buck-type constant power load[J]. IEEE Transactions on Power Electronics, 2022, 37(8): 8909-8920.
[14] Wu Mingfei, Lu D D C, Tse C K. Direct and optimal linear active methods for stabilization of LC input filters and DC/DC converters under voltage mode control[J]. IEEE Journal on Emerging and Selected Topics in Circuits and Systems, 2015, 5(3): 402-412.
[15] Zeng Chengbi, Wang Hanwen, Li Sudan, et al.Grid-voltage-feedback active damping with lead compensation for LCL-type inverter connected to weak grid[J]. IEEE Access, 2021, 9: 106813-106823.
[16] 谢文浩, 刘一琦, 王建赜, 等. 提高LCL型并网逆变器阻抗重塑控制鲁棒性的延时补偿方法[J]. 电工技术学报, 2017, 32(增刊1): 178-185.
Xie Wenhao, Liu Yiqi, Wang Jianze, et al.A delay compensation method of the grid-connected inverter with LCL filter to improve robustness of the impedance shaping control[J]. Transactions of China Electrotechnical Society, 2017, 32(S1): 178-185.
[17] Yao Wenli, Yang Yongheng, Zhang Xiaobin, et al.Design and analysis of robust active damping for LCL filters using digital Notch filters[J]. IEEE Transactions on Power Electronics, 2017, 32(3): 2360-2375.
[18] 金国彬, 苑忠奇, 李国庆, 等. 基于无源性的并网逆变器扩展阻尼区域方法研究[J]. 电力系统保护与控制, 2022, 50(19): 25-35.
Jin Guobin, Yuan Zhongqi, Li Guoqing, et al.A method of extending the damping region of a grid-connected inverter based on passivity[J]. Power System Protection and Control, 2022, 50(19): 25-35.
[19] 王林, 孙鹏菊, 薛统宇, 等. 一种提高LCL型并网逆变器电流控制性能的延时补偿方法[J]. 中国电机工程学报, 2020, 40(19): 6320-6330.
Wang Lin, Sun Pengju, Xue Tongyu, et al.A delay compensation method to improve the current control performance of the LCL-type grid-connected inverter[J]. Proceedings of the CSEE, 2020, 40(19): 6320-6330.
[20] 姜鑫, 易皓, 卓放, 等. 基于直流电压同步的构网型变流器低频振荡分析与阻尼控制[J]. 电力系统自动化, 2024, 48(16): 30-39.
Jiang Xin, Yi Hao, Zhuo Fang, et al.Low-frequency oscillation analysis and damping control for grid-forming converters based on DC voltage synchronization[J]. Automation of Electric Power Systems, 2024, 48(16): 30-39.
[21] 刘海春, 过仕安, 钱强, 等. 基于基准频率自适应谐波准谐振控制器的宽变频逆变电源控制研究[J]. 电工技术学报, 2024, 39(20): 6462-6474.
Liu Haichun, Guo Shian, Qian Qiang, et al.Research on control of wideband variable-frequency inverters based on harmonics quasi resonant controller with frequency reference adapting[J]. Transactions of China Electrotechnical Society, 2024, 39(20): 6462-6474.
[22] 杨龙月, 郭锐, 张乐, 等. 非理想电网下逆变器并网电流质量改善策略[J]. 电力系统保护与控制, 2020, 48(15): 10-18.
Yang Longyue, Guo Rui, Zhang Le, et al.Improvement strategy for grid-connected current quality of an inverter under non-ideal grid conditions[J]. Power System Protection and Control, 2020, 48(15): 10-18.
[23] 熊小玲, 罗博晨, 刘京波, 等. 计及SVG的双馈风电场高频阻抗建模及振荡分析[J]. 电网技术, 2023, 47(7): 2905-2917.
Xiong Xiaoling, Luo Bochen, Liu Jingbo, et al.High frequency impedance modeling and oscillation analysis of DFIG-based station considering SVG[J]. Power System Technology, 2023, 47(7): 2905-2917.
[24] Sun Jian.Impedance-based stability criterion for grid-connected inverters[J]. IEEE Transactions on Power Electronics, 2011, 26(11): 3075-3078.
[25] Agorreta J L, Borrega M, López J, et al.Modeling and control of $N$-paralleled grid-connected inverters with LCL filter coupled due to grid impedance in PV plants[J]. IEEE Transactions on Power Electronics, 2011, 26(3): 770-785.
[26] 曹子恒, 肖先勇, 马俊鹏, 等. 提高LCL型并网逆变器鲁棒性的改进型电容电流反馈有源阻尼策略[J]. 高电压技术, 2020, 46(11): 3781-3790.
Cao Ziheng, Xiao Xianyong, Ma Junpeng, et al.Novel capacitor current feedback active damping strategy for enhancing robustness of LCL-type grid-connected inverters[J]. High Voltage Engineering, 2020, 46(11): 3781-3790.
[27] Su Xinyang, Wang Minghao, Zhao Bi'an, et al. An adaptive compensated virtual impedance method for oscillation suppression in DC distribution power systems[J]. IEEE Transactions on Industrial Electronics, 2024, PP(99): 1-11.