Diode Rectifier Unit Based LFAC Transmission for Offshore Wind Farm Integration

doi:10.11930/j.issn.1004-9649.202005071

Abstract

Abstract: The offshore wind power, which is high in density and small in fluctuation, will be the focus for wind power development in the future. Up to now, the offshore wind power transmission projects in operation have mostly adopted VSC-HVDC technology, whereas their capital cost is relatively high. So, this paper proposes a diode uncontrolled unit (DRU) based low frequency alternative current (LFAC) transmission scheme for the offshore wind farms, in which the offshore platform of the rectifier is cancelled and the rectifier in the traditional AC-DC-AC frequency converter is substituted by the DRU, thus significantly reducing the project investment and operating cost. Since the DRU is uncontrolled, a corresponding control strategy of the offshore wind turbines is proposed for LFAC transmission system, in which the machine side converter (MSC) controls the DC voltage and the grid side converter (GSC) implements the maximum power point tracking (MPPT) and AC voltage control together in the global unified reference coordinate system. Case simulations in PSCAD/EMTDC were carried out in the end to study the system response to typical operating conditions including wind power fluctuation and three-phase faults in the onshore grid and offshore grid, and the feasibility of the proposed scheme is verified.

Key words: offshore wind power, DRU, LFAC transmission system, fully rated converter based wind turbine, global unified reference coordinate system

TANG Yingjie, ZHANG Zheren, XU Zheng. Diode Rectifier Unit Based LFAC Transmission for Offshore Wind Farm Integration[J]. Electric Power, 2020, 53(7): 44-54,168.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.202005071

https://www.electricpower.com.cn/EN/Y2020/V53/I7/44

References

[1] 李翔宇, Gayan Abeynayake, 姚良忠, 等. 欧洲海上风电发展现状及前景[J]. 全球能源互联网, 2019(2): 116-126
LI Xiangyu, ABEYNAYAKE G, YAO Liangzhong, et al. Recent development and prospect of offshore wind power in Europe[J]. Journal of Global Energy Interconnection, 2019(2): 116-126
[2] 蔡旭, 陈根, 周党生, 等. 海上风电变流器研究现状与展望[J]. 全球能源互联网, 2019(2): 102-115
CAI Xu, CHEN Gen, ZHOU Dangsheng, et al. Review and prospect on key technologies for offshore wind power converters[J]. Journal of Global Energy Interconnection, 2019(2): 102-115
[3] ANDERSSON D, PETERSSON A, AGNEHOLM E, et al. Kriegers flak 640 MW off-shore wind power grid connection: a real project case study[J]. IEEE Transactions on Energy Conversion, 2007, 22(1): 79-85.
[4] LIU W T, WU Y K, LEE C Y, et al. Effect of low-voltage-ride-through technologies on the first Taiwan offshore wind farm planning[J]. IEEE Transactions on Sustainable Energy, 2011, 2(1): 78-86.
[5] 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. 22-26 July 2012, San Diego, CA, USA. IEEE, 2012: 1-7.
[6] BRESESTI P, KLING W L, HENDRIKS R L, et al. HVDC connection of offshore wind farms to the transmission system[J]. IEEE Transactions on Energy Conversion, 2007, 22(1): 37-43.
[7] 王锡凡, 卫晓辉, 宁联辉, 等. 海上风电并网与输送方案比较[J]. 中国电机工程学报, 2014, 34(31): 5459-5466
WANG Xifan, WEI Xiaohui, NING Lianhui, et al. Integration techniques and transmission schemes for off-shore wind farms[J]. Proceedings of the CSEE, 2014, 34(31): 5459-5466
[8] MUYEEN S M, TAKAHASHI R, TAMURA J. Operation and control of HVDC-connected offshore wind farm[J]. IEEE Transactions on Sustainable Energy, 2010, 1(1): 30-37.
[9] MITRA P, ZHANG L D, HARNEFORS L. Offshore wind integration to a weak grid by VSC-HVDC links using power-synchronization control: a case study[J]. IEEE Transactions on Power Delivery, 2014, 29(1): 453-461.
[10] CAI L, KARAAGAC U, MAHSEREDJIAN J. Simulation of startup sequence of an offshore wind farm with MMC-HVDC grid connection[J]. IEEE Transactions on Power Delivery, 2017, 32(2): 638-646.
[11] FUNAKI T, MATSUURA K. Feasibility of the low frequency AC transmission[C]//2000 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.00CH37077). 23-27 Jan. 2000, Singapore, Singapore. IEEE, 2000: 2693-2698.
[12] 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. 26-30 July 2009, Calgary, AB, Canada. IEEE, 2009: 1-8.
[13] WANG X F, CAO C J, ZHOU Z C. Experiment on fractional frequency transmission system[J]. IEEE Transactions on Power Systems, 2006, 21(1): 372-377.
[14] CHEN H, JOHNSON M H, ALIPRANTIS D C. Low-frequency AC transmission for offshore wind power[J]. IEEE Transactions on Power Delivery, 2013, 28(4): 2236-2244.
[15] 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. 29 June-2 July 2015, Eindhoven, Netherlands. IEEE, 2015: 1-6.
[16] CHAITHANYA S, REDDY V N B, KIRANMAYI R. A narrative review on offshore wind power transmission using low frequency AC system[C]//2017 International Conference on Smart Technologies for Smart Nation (SmartTechCon). 17-19 Aug. 2017, Bangalore, India. IEEE, 2017: 52-58.
[17] RUDDY J, MEERE R, O’DONNELL T. Low Frequency AC transmission for offshore wind power: a review[J]. Renewable and Sustainable Energy Reviews, 2016, 56: 75-86.
[18] LIU S Q, WANG X F, NING L H, et al. Integrating offshore wind power via fractional frequency transmission system[J]. IEEE Transactions on Power Delivery, 2017, 32(3): 1253-1261.
[19] XIANG X, MERLIN M M C, GREEN T C. Cost analysis and comparison of HVAC, LFAC and HVDC for offshore wind power connection[C]//12th IET International Conference on AC and DC Power Transmission (ACDC 2016), Beijing, China. Institution of Engineering and Technology, 2016: 1-6.
[20] FOSTER S, XU L, FOX B. Control of an LCC HVDC system for connecting large offshore wind farms with special consideration of grid fault[C]//2008 IEEE Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century. 20-24 July 2008, Pittsburgh, PA, USA. IEEE, 2008: 1-8.
[21] 徐政. 高比例非同步机电源电网面临的三大技术挑战[J]. 南方电网技术, 2020, 14(2): 1-9
XU Zheng. Three technical challenges faced by power grids with high proportion of non-synchronous machine sources[J]. Southern Power System Technology, 2020, 14(2): 1-9
[22] HERRERA D, GALVáN E, CARRASCO J M. Method for controlling voltage and frequency of the local offshore grid responsible for connecting large offshore commercial wind turbines with the rectifier diode-based HVDC-link applied to an external controller[J]. IET Electric Power Applications, 2017, 11(9): 1509-1516.
[23] NERIS A S, VOVOS N A, GIANNAKOPOULOS G B. A variable speed wind energy conversion scheme for connection to weak AC systems[J]. IEEE Transactions on Energy Conversion, 1999, 14(1): 122-127.
[24] 于洋, 徐政, 徐谦, 等. 永磁直驱式风机采用混合直流并网的控制策略[J]. 中国电机工程学报, 2016, 36(11): 2863-2870
YU Yang, XU Zheng, XU Qian, et al. A control strategy for integration of permanent magnet direct-driven wind turbines through a hybrid HVDC system[J]. Proceedings of the CSEE, 2016, 36(11): 2863-2870
[25] 周长春, 徐政. 直流输电准稳态模型有效性的仿真验证[J]. 中国电机工程学报, 2003, 23(12): 33-36
ZHOU Changchun, XU Zheng. Simulation validity test of the hvdc quasi-steady-state model[J]. Proceedings of the CSEE, 2003, 23(12): 33-36
[26] YU L J, LI R, XU L. Distributed PLL-based control of offshore wind turbines connected with diode-rectifier-based HVDC systems[J]. IEEE Transactions on Power Delivery, 2018, 33(3): 1328-1336.
[27] ROCABERT J, LUNA A, BLAABJERG F, et al. Control of power converters in AC microgrids[J]. IEEE Transactions on Power Electronics, 2012, 27(11): 4734-4749.
[28] CHUNG S K. A phase tracking system for three phase utility interface inverters[J]. IEEE Transactions on Power Electronics, 2000, 15(3): 431-438.
[29] DONG D, WEN B, MATTAVELLI P, et al. Grid-synchronization modeling and its stability analysis for multi-paralleled three-phase inverter systems[C]//2013 Twenty-Eighth Annual IEEE Applied Power Electronics Conference and Exposition (APEC). 17-21 March 2013, Long Beach, CA, USA. IEEE, 2013: 439-446.
[30] BURGOS R, BOROYEVICH D, WANG F, et al. On the Ac stability of high power factor three-phase rectifiers[C]//2010 IEEE Energy Conversion Congress and Exposition. 12-16 Sept. 2010, Atlanta, GA, USA. IEEE, 2010: 2047-2054.
[31] RADWAN A A A, MOHAMED Y A R I. Analysis and active-impedance-based stabilization of voltage-source-rectifier loads in grid-connected and isolated microgrid applications[J]. IEEE Transactions on Sustainable Energy, 2013, 4(3): 563-576.
[32] WEN B, BOROYEVICH D, BURGOS R, et al. Analysis of D-Q small-signal impedance of grid-tied inverters[J]. IEEE Transactions on Power Electronics, 2016, 31(1): 675-687.
[33] WEN B, DONG D, BOROYEVICH D, et al. Impedance-based analysis of grid-synchronization stability for three-phase paralleled converters[J]. IEEE Transactions on Power Electronics, 2016, 31(1): 26-38.
[34] YE H, LIU Y, QI Z P, et al. A low-order AC-frequency and DC-voltage response model of HVDC grid connected with wind farms[C]//2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC). 25-28 Oct. 2016, Xi'an, China. IEEE, 2016: 681-686.6.
[35] G?KSU ?, TEODORESCU R, BAK C L, et al. Instability of wind turbine converters during current injection to low voltage grid faults and PLL frequency based stability solution[J]. IEEE Transactions on Power Systems, 2014, 29(4): 1683-1691.
[36] GIERSCHNER M, KNAAK H J, ECKEL H G. Fixed-reference-frame-control: a novel robust control concept for grid side inverters in HVDC connected weak offshore grids[C]//2014 16th European Conference on Power Electronics and Applications. 26-28 Aug. 2014, Lappeenranta, Finland. IEEE, 2014: 1-7.
[37] PRIGNITZ C, ECKEL H G, ACHENBACH S, et al. FixReF: a control strategy for offshore wind farms with different wind turbine types and diode rectifier HVDC transmission[C]//2016 IEEE 7th International Symposium on Power Electronics for Distributed Generation Systems (PEDG). 27-30 June 2016, Vancouver, BC, Canada. IEEE, 2016: 1-7.
[38] SHIN H, JUNG H S, SUL S K. Low Voltage Ride Through(LVRT) control strategy of grid-connected variable speed Wind Turbine Generator System[C]//8th International Conference on Power Electronics - ECCE Asia. 30 May-3 June 2011, Jeju, South Korea. IEEE, 2011: 96-101.
[39] 郭贤珊, 周杨, 梅念, 等. 张北柔直电网的构建与特性分析[J]. 电网技术, 2018, 42(11): 3698-3707
GUO Xianshan, ZHOU Yang, MEI Nian, et al. Construction and characteristic analysis of Zhangbei flexible DC grid[J]. Power System Technology, 2018, 42(11): 3698-3707