海上风电直流送出与并网技术综述

随着深远海风电开发利用的快速发展,风电直流送出与并网成为技术热点.针对风电交流汇集直流送出、低成本直流送出、多端直流送出和多电压等级直流送出技术,全面论述了海上风电直流送出技术在系统拓扑、装备、控制与保护方面的现状和存在的问题,以及研究热点和发展趋势,指出海上风电场集群共享直流集中送出是近期的主流方案,系统的宽频振荡是亟待解决的问题,使整体系统体现主导电源特征是关注的热点.为降低成本,基于二极管整流送出的技术路线具有良好的预期,但纯二极管整流送出需要风电机组的改进.海上风电多端直流并网系统的成熟依赖于低成本直流断路器和暂态控制保护技术的进步,而海上风电多电压等级直流并网系统尚缺乏直流变压器等关键装备的支撑.

Review on Offshore Wind Power Integration via DC Transmission

With the rapid development of deep and distant offshore wind power, the transmission and the grid integration of wind power via HVDC systems have become technical hotspots. Focusing on several vital technologies such as AC collection-based DC transmission, low-cost DC transmission, multi-terminal DC transmission and multi-voltage-level DC transmission, the paper comprehensively discusses the current status, existing problems, research hotspots and development trends of the offshore wind power via DC transmission technologies in terms of system topology, equipment, control and protection. It is pointed out that the transmission and grid integration of offshore wind farms via the centralized HVDC system is the mainstream scheme in the near future. For such a system, the broadband oscillation is an urgent problem to be solved, it is the focus of attention to make the whole system perform the characteristics of dominant power sources. In terms of cost reduction, the technical route of the diode rectifier based HVDC transmission system has good features. However, to use pure diode rectifiers as the sending-end converter requires the improvement of wind turbines. For the multi-terminal DC grid with wind power integration, the development depends on the progress of low-cost DC circuit breaker and transient control and protection technology. And the offshore wind power transmission and grid integration via multi-voltage-level DC grid still lacks the support of the DC transformer and other key equipment.