张哲任,徐政,黄莹,裘鹏,徐文哲
ZHANG Zheren,XU Zheng,HUANG Ying,QIU Peng,XU Wenzhe

• 1:浙江大学电气工程学院
• 2:国网浙江省电力有限公司电力科学研究院

摘要(Abstract)：

藏东南地区光伏资源丰富，其大规模开发利用契合我国“双碳”目标，亟需确定合适的汇集与送出方式。受限于西藏地区自然环境与电网建设条件，具备输送距离远、同电压等级下输送容量大、不存在无功电压支撑问题等优点的全直流汇集与送出方案较传统交流方案更具优势。首先，基于藏东南光伏基地汇集送出场景，提出全直流汇集送出推荐组网方案。然后，针对直流变压器和泄能装置等关键设备的拓扑结构、系统接地方案、系统控制保护策略进行探讨。最后，在PSCAD/EMTDC中搭建10 000 MW光伏全直流汇集送出系统仿真模型，验证了所提藏东南光伏基地全直流系统方案的可行性。
Southeast Tibet is rich in photovoltaic energy, and its large-scale utilization is in line with China's carbon peaking and carbon neutrality goals. Thus, it is urgent to choose an appropriate collection and transmission method.Limited by the natural environment and power grid construction conditions in southeast Tibet, the full DC collection and transmission scheme with the advantages of long transmission distance, no reactive power problems, and high efficiency is superior to the traditional AC scheme. Firstly, a recommended networking mode for a full DC collection and transmission scheme is proposed in view of the collection and transmission scenarios of a photovoltaic base in southeast Tibet. Secondly, the topology of the key equipment, such as DC transformers and energy dissipation devices, the system grounding scheme and its control and protection strategies are discussed. Finally, a simulation model of a 10, 000 MW photovoltaic full DC collection and transmission system is built in PSCAD/EMTDC, and the feasibility of the proposed scheme for the photovoltaic in southeast Tibet is verified.

关键词(KeyWords)： 藏东南地区;光伏基地;全直流组网;直流变压器;控制保护
southeast Tibet;photovoltaic base;full DC networking;DC transformer;control and protection

Abstract:

Keywords:

基金项目(Foundation): 中央高校基本科研业务专项（2021QNA4014）

作者(Author): 张哲任,徐政,黄莹,裘鹏,徐文哲
ZHANG Zheren,XU Zheng,HUANG Ying,QIU Peng,XU Wenzhe

参考文献(References)：

• [1]卓振宇，张宁，谢小荣，等.高比例可再生能源电力系统关键技术及发展挑战[J].电力系统自动化，2021,45(9):171-191.ZHUO Zhenyu,ZHANG Ning,XIE Xiaorong,et al.Key technologies and developing challenges of power system with high proportion of renewable energy[J].Automation of Electric Power Systems,2021,45(9):171-191.
• [2]李鹏.高海拔地区大型电网建设项目后评价体系及实证研究[D].北京：华北电力大学，2016.LI Peng.An empirical study of the post evaluation system for high altitude areas of large power grid construction project[D]. Beijing:North China Electric Power University,2016.
• [3] ECHEVERRíA J,KOURO S,PéREZ M,et al. Multimodular cascaded DC-DC converter for HVDC grid connection of large-scale photovoltaic power systems[C]//IECON 2013-39th Annual Conference of the IEEE Industrial Electronics Society.November 10-13,2013,Vienna,Austria:IEEE,2014:6999-7005.
• [4]姚美齐，蔡旭.大型光伏电站内网拓扑结构比较分析[J].电网技术，2017,41(5):1406-1411.YAO Meiqi,CAI Xu.Comparative analysis of different topologies for large PV plants[J].Power System Technology,2017,41(5):1406-1411.
• [5]杨晓峰，郑琼林，林智钦，等.用于直流电网的大容量DC/DC变换器研究综述[J].电网技术，2016,40(3):670-677.YANG Xiaofeng,ZHENG Trillion Q,LIN Zhiqin,et al.Survey of high-power DC/DC converter for HVDC grid application[J].Power System Technology,2016,40(3):670-677.
• [6] GU B,DOMINIC J,CHEN B F,et al.Hybrid transformer ZVS/ZCS DC-DC converter with optimized magnetics and improved power devices utilization for photovoltaic module applications[J]. IEEE Transactions on Power Electronics,2015,30(4):2127-2136.
• [7]黄欣科，王环，周宇，等.兆瓦级光伏中压直流并网变换器研制及实证应用[J].电力系统自动化，2022,46(14):150-157.HUANG Xinke,WANG Huan,ZHOU Yu,et al.Development and empirical application of megawatt-level mediumvoltage DC photovoltaic grid-connected converter[J].Automation of Electric Power Systems,2022,46(14):150-157.
• [8]顾亦磊.集成模块电源拓扑标准化的研究[D].杭州：浙江大学，2008.GU Yilei. Research of topology standardization for integrated power modules[D]. Hangzhou:Zhejiang University,2008.
• [9]张轩，张翀，陈杰涛，等.LLC谐振型DC/DC变换器在光伏并网系统中的应用研究[J].电子技术，2018,47(11):47-54.ZHANG Xuan,ZHANG Chong,CHEN Jietao,et al.Research on the application of LLC resonant DC/DC converter in photovoltaic grid connected system[J].Electronic Technology,2018,47(11):47-54.
• [10]卢世蕾，孙凯，曹国恩，等.面向光伏直流升压系统的高压大功率LLC谐振变换器设计方法[J/OL].中国电机工程学报：1-14[2023-02-15]. https：//doi. org/10.13334/j.0258-8013.pcsee.222575.LU Shilei,SUN Kai,CAO Guoeng,et al. A design method of high voltage and high power LLC resonant converter for photovoltaic DC voltage boosting system[J/OL].Proceedings of the CSEE,2023:1-14.[2023-02-15].https：//doi.org/10.13334/j.0258-8013.pcsee.222575.
• [11] KENZELMANN S,RUFER A,DUJIC D,et al.Isolated DC/DC structure based on modular multilevel converter[J]. IEEE Transactions on Power Electronics,2015,30(1):89-98.
• [12] MERLIN M M C,GREEN T C,MITCHESON P D,et al. The alternate arm converter:a new hybrid multilevel converter with DC-fault blocking capability[J]. IEEE Transactions on Power Delivery,2014,29(1):310-317.
• [13]余滢婷，刘飞，查晓明，等.光伏电站直流汇集系统电压等级序列研究[J].太阳能学报，2020,41(10):182-189.YU Yingting,LIU Fei,ZHA Xiaoming,et al.DC convergence system voltage class series for PV power station[J].Acta Energiae Solaris Sinica,2020,41(10):182-189.
• [14] ROJAS C A,KOURO S,PEREZ M A,et al. DC-DC MMC for HVDC grid interface of utility-scale photovoltaic conversion systems[J].IEEE Transactions on Industrial Electronics,2018,65(1):352-362.
• [15]奚鑫泽，黄文焘，张茗沁，等.大型光伏电站直流升压汇集接入系统协同控保体系与方案研究[J].供用电，2018,35(8):52-60.XI Xinze,HUANG Wentao,ZHANG Mingqin,et al.Research on cooperative control and protection system and scheme of DC step-up collection system for large-scale photovoltaic power plants[J]. Distribution&Utilization,2018,35(8):52-60.
• [16]奚鑫泽，徐志，高尚.直流变压器光伏中压并网故障运行特性研究[J].电力科学与技术学报，2020,35(5):89-95.XI Xinze,XU Zhi,GAO Shang. Fault operation of DC transformer for the PV medium voltage DC grid[J].Journal of Electric Power Science and Technology,2020,35(5):89-95.
• [17]安婷，乐波，杨鹏，等.直流电网直流电压等级确定方法[J].中国电机工程学报，2016,36(11):2871-2879.AN Ting,YUE Bo,YANG Peng,et al.A determination method of DC voltage levels for DC grids[J].Proceedings of the CSEE,2016,36(11):2871-2879.
• [18] KENZELMANN S,RUFER A,DUJIC D,et al.A versatile DC/DC converter based on Modular Multilevel Converter for energy collection and distribution[C]//IET Conference on Renewable Power Generation(RPG2011). September 6-8,2011,Edinburgh,London:IET,2012:1-6.
• [19]索之闻.基于MMC的高压大功率DC/DC变换器拓扑与控制策略研究[D].北京：华北电力大学，2017.SUO Zhiwen. Research on topologies and control strategies of MMC based high-power high-voltage DC/DC converter[D]. Beijing:North China Electric Power University,2017.
• [20]蔡普成，向往，周猛，等.基于混合型MMC和快速真空开关构建的柔性直流电网[J].南方电网技术，2019,13(11):42-50.CAI Pucheng,XIANG Wang,ZHOU Meng,et al.VSCHVDC power grid based on hybrid MMC and fast vacuum breaker[J].Southern Power System Technology,2019,13(11):42-50.
• [21]屈鲁，余占清，陈政宇，等.三端口混合式直流断路器的工程应用[J].电力系统自动化，2019,43(23):141-146.QU Lu,YU Zhanqing,CHEN Zhengyu,et al.Engineering application of three-terminal hybrid DC circuit breaker[J].Automation of Electric Power Systems,2019,43(23):141-146.