宁联辉,王琦晨,杨勇,赵连忠,仪力萌,周治伊
NING Lianhui,WANG Qichen,YANG Yong,ZHAO Lianzhong,YI Limeng,ZHOU Zhiyi

• 1:西安交通大学电气工程学院
• 2:国网甘肃省电力公司电力科学研究院

摘要(Abstract)：

分频输电系统在提升输电容量、改善输电通道末端电压质量等方面具有优越性,在大规模深远海风电送出等场合有着广泛的应用前景。为研究分频海上风电系统中海底电缆的低频特性,利用Comsol Multiphysics有限元分析软件建立了海底电缆的磁电热仿真模型,分析了低频环境对其电流分布、运行损耗、运行温度及金属护套接地方式的影响。仿真结果表明:频率降低可改善导体的电流分布,降低海缆各部分损耗,从而降低海缆的运行温度,提高载流量;同时,分频输电可有效改善2种接地方式下屏蔽层的感应电势和环流损耗,能够有效扩大2种接地方式的适用范围。因此,在长距离输送的场景下,采用分频输电方式有助于提高电缆载流量,减少容性充电功率,实现功率传输大幅增长,提升分频海上风电系统的经济性。
Superior in improving transmission capacity and terminal voltage quality of transmission channel,fractional frequency transmission system(FFTS) has a wide application prospect in large-scale deep-sea wind power transmission. In order to study the low frequency characteristics of submarine cables in fractional frequency offshore wind power system, this paper establishes a magneto-electro-thermal simulation model of submarine cables using Comsol Multiphysics finite element analysis software and analyzes the influence of low-frequency environment on current distribution, operating loss, operating temperature and grounding mode of metal sheath. The simulation results show that the frequency reduction improves the conductor current distribution, reduces the loss of each part of the cable, and thus reduces the operating temperature of the cable and increases the current-carrying capacity. At the same time, the fractional frequency transmission system can effectively improve the induced potential and circulation loss in the shielding layers under the two grounding modes, and can effectively expand the application range of the two grounding modes. Therefore, in the scenario of long-distance transmission, the fractional frequency transmission mode is conducive to the improvement of cable carrying capacity and the reduction of capacitive charging power, thus achieving a substantial increase in power transmission and improving the economy of fractional frequency offshore wind power system.

关键词(KeyWords)： 分频风电系统;海底电缆;频率特性;经济性
fractional frequency wind power system;submarine cable;frequency characteristics;economy

Abstract:

Keywords:

基金项目(Foundation): 2020年国网总部项目（5500-202099509A-0-0-00）

作者(Author): 宁联辉,王琦晨,杨勇,赵连忠,仪力萌,周治伊
NING Lianhui,WANG Qichen,YANG Yong,ZHAO Lianzhong,YI Limeng,ZHOU Zhiyi

DOI: 10.19585/j.zjdl.202112013

参考文献(References)：

• [1]王锡凡.分频输电系统[J].中国电力，1995(1):2-6.
• [2]王锡凡，刘沈全，宋卓彦，等.分频海上风电系统的技术经济分析[J].电力系统自动化，2015,39(3):43-50.
• [3]FISCHER W,BRAUN R,ERLICH I.Low frequency high voltage offshore grid for transmission of renewable power[C]//2012 3rd IEEE PES Innovative Smart Grid Technologies Europe(ISGT Europe),2012:1-6.
• [4]QIN N,YOU S,XU Z,et al.Offshore wind farm connection with low frequency AC transmission technology[C]//2009 IEEE Power&Energy Society General Meeting,[S.l.:s.n.],2009:1-8.
• [5]RUDDY J,MEERE R,O′DONNELL T.A comparison of VSC-HVDC with low frequency AC for offshore wind farm design and interconnection[J].Energy Procedia,2015,80:185-192.
• [6]黄明煌，王秀丽，刘沈全，等.分频输电应用于深远海风电并网的技术经济性分析[J].电力系统自动化，2019,43(5):167-174.
• [7]FISCHER W,BRAUN R,ERLICH I.Low frequency high voltage offshore grid for transmission of renewable power[C]//2012 3rd IEEE PES Innovative Smart Grid Technologies Europe(ISGT Europe),[S.l.:s.n.],2012:1-6.
• [8]WYLLIE P B,TANG Y,RAN L,et al.Low frequency AC transmission-elements of a design for wind farm connection[C]//11th IET International Conference on AC and DC Power Transmission,[S.l.:s.n.],2015:1-5.
• [9]RUDDY J,MEERE R,O'DONNELL T. Low Frequency AC transmission as an alternative to VSC-HVDC for grid interconnection of offshore wind[C]//2015 IEEE Eindhoven PowerTech,[S.l.:s.n.],2015:1-6.
• [10]MAU C N,RUDION K,ORTHS A,et al.Grid connection of offshore wind farm based DFIG with low frequency AC transmission system[C]//2012 IEEE Power and Energy Society General Meeting,[S.l.:s.n.],2012:1-7.
• [11]刘奎.分频风电并网的潮流计算及无功控制策略研究[D].西安：西安交通大学，2010.
• [12]RUDDY J,MEERE R,O′LOUGHLIN C,et al.Design of VSC connected low frequency AC offshore transmission with long HVAC cables[J].IEEE Transactions on Power Delivery,2018,33(2):960-970.
• [13]NGO T,LWIN M,SANTOSO S.Analysis of distance protection in low frequency AC transmission systems[C]//2016IEEE Power and Energy Society General Meeting(PESGM),[S.l.:s.n.],2016:1-5.
• [14]LI J,ZHANG X P.Small signal stability of fractional fre quency transmission system with offshore wind farms[J].IEEE Transactions on Sustainable Energy,2016,7(4):1538-1546.
• [15]DONG J,ATTYA A B,ANAYA-LARA O.Frequency stability analysis in low frequency AC systems for renewables power transmission[C]//2017 6th International Conference on Clean Electrical Power(ICCEP).Santa Margherita Ligure,Italy.IEEE,2017:275-279.
• [16]NGO T,LWIN M,SANTOSO S.Steady-state analysis and performance of low frequency AC transmission lines[J].IEEE Transactions on Power Systems,2016,31(5):3873-3880.
• [17]NGO T,SANTOSO S.Modal-based voltage stability anal ysis of low frequency AC transmission systems[J].2016IEEE Power and Energy Society General Meeting(PESGM),2016:1-5.
• [18]吕超，李赫，王劭，等.基于0.1 Hz超低频的XLPE电缆介质损耗老化评估[J].内蒙古电力技术，2021,39(1):68-71.
• [19]范慧敏.城市电网柔性低频电缆输电系统稳态特性研究[D].北京：华北电力大学，2017.
• [20]汪小清，吴聂根.220 kV交流OF海缆和XLPE海缆绝缘的优劣及国外生产应用情况[J].福建水力发电，2017(2):72-73.
• [21]周厚强，许勇君，张磊，等.沿海风电场用三芯XLPE海底电缆设计方案的可行性分析[J].中国电业（技术版），2012(5):61-63.
• [22]沈佩芳.220 kV大长度光纤复合海底电力电缆的研制[J].电线电缆，2010(6):1-3.
• [23]秦春旭，栗丙典，李国明，等.基于有限元对220 kV三芯海缆温度场的数值计算[J].东北电力大学学报，2019,39(4):5-10.
• [24]陈梦曦.10 kV三芯电缆接头温度场的仿真研究[D].西安：西安科技大学，2019.
• [25]张畅生，刘龙春，陈隽.110 kV海底电缆接地方式对载流量和环流的影响[J].广东电力，2017,30(8):122-127.
• [26]刘杰.高压电缆护套环流分析及防范措施[J].通信电源技术，2013,30(6):58-61.