中国电力 ›› 2020, Vol. 53 ›› Issue (7): 80-91.DOI: 10.11930/j.issn.1004-9649.202005085

• 远海风电送出关键技术专栏 • 上一篇    下一篇

采用中频不控整流直流系统的远海风电送出方案

张哲任, 唐英杰, 徐政   

  1. 浙江大学 电气工程学院,浙江 杭州 310027
  • 收稿日期:2020-05-11 修回日期:2020-05-25 发布日期:2020-07-05
  • 作者简介:张哲任(1988—),男,博士,特聘副研究员,从事直流输电与柔性交流输电、新能源并网技术研究,E-mail: zhangzheren@zju.edu.cn;唐英杰(1996—),男,博士研究生,从事直流输电和电磁暂态仿真研究,E-mail: 11810049@zju.edu.com;徐政(1962—),男,通信作者,博士,教授,博导,从事大规模交直流电力系统分析、直流输电与柔性交流输电、风力发电技术与风电场并网技术研究,E-mail: xuzheng007@zju.edu.com

Medium Frequency Diode Rectifier Unit Based HVDC Transmission for Offshore Wind Farm Integration

ZHANG Zheren, TANG Yingjie, XU Zheng   

  1. College of Electric Engineering, Zhejiang University, Hangzhou 310027, China
  • Received:2020-05-11 Revised:2020-05-25 Published:2020-07-05

摘要: 远海风电场具有更加丰富和稳定的风能资源,是未来风电发展的主要趋势,目前远海风电主要通过柔性直流系统并网。整流侧采用二极管不控整流单元(diode rectifier unit, DRU)具有明显的经济优势和发展前景,是学术界和工业界的研究热点。为了进一步提高远海风电送出系统的经济性,以整流侧采用DRU的高压直流输电系统为基本拓扑,提出采用中频不控整流直流系统的远海风电送出方案,通过把风电场交流电网的运行频率选为100~400 Hz,可以大幅度减小升压变压器和交流滤波器的体积和重量。同时,提出适用于中频不控整流直流系统的风电机组控制策略,其中,机侧换流器采用定直流电压控制,网侧换流器在全局统一参考坐标系下同时实现定功率控制和定交流侧电压控制。最后,通过PSCAD/EMTDC进行算例仿真,对所提方案的可行性进行验证。

关键词: 远海风电, 中频风电场, 构网型换流器, 二极管不控整流单元, 全局统一参考坐标系

Abstract: The offshore wind farms are the main trend of the wind power development in the future. Till now, the commissioned far offshore wind farms are always connected to the onshore AC system by VSC-HVDC systems. The hybrid HVDC topology with uncontrolled diode rectifier unit (DRU) has drawn attentions from both the academia and the industry, due to its economic benefits. In order to further improve the economic efficiency of far offshore wind power transmission systems, this paper proposed the medium frequency uncontrolled rectifier offshore wind power transmission system based on the DRU at the rectifier side. The offshore ac system rated frequency of the proposed system is set as 100~400 Hz, which could significantly decrease the weight and the volume of the transformer and the AC filters at the offshore platform. The corresponding control scheme of the wind turbine are also proposed, where the machine side converter controls the DC voltage and the grid side converter controls the machine power and the AC side voltage together in the global unified reference coordinate system. Based on time domain simulations in PSCAD/EMTDC, the feasibility of the proposed schemes is verified.

Key words: offshore wind farm, medium frequency wind farm, grid forming converter, diode rectifier unit (DRU), global unified reference coordinate system