用于大容量风机直流并网的二重化三电平软开关变换器  

Dual Three-level Soft Switching Converter for DC Grid-connected of Large-scaled Wind Turbines

作　　者：洪诚程 刘其辉 刘懿欣 樊双婕 田鑫 袁振华 HONG Chengcheng;LIU Qihui;LIU Yixin;FAN Shuangjie;TIAN Xin;YUAN Zhenhua(State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China;State Grid Shandong Economic&Technology Research Institute,Ji’nan 250021,Shandong Province,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206 [2]国网山东省电力公司经济技术研究院,山东省济南市250021

出　　处：《电网技术》2023年第5期2108-2118,共11页Power System Technology

基　　金：国家电网有限公司总部管理科技项目(5100-202199543A-0-5-ZN)。

摘　　要：随着海上风电场容量的扩大和离岸距离的增加,避免了无功电压问题的直流风电场得到了日益广泛的关注。直驱风机作为海上风电开发的主流机型,通过DC/DC变换器的设计可实现直流并网。首先,依据机组直流并网需求提出了一种二重化三电平软开关DC/DC变换器方案,在减小变换器体积的同时有效降低了变换器的开关损耗;其次,在详细分析子变换器工作原理的基础上给出子变换器重要参数的设计方法;然后,依据DC/DC变换器的控制目标,给出了其在稳态和故障阶段的控制策略,实现了机组的安全稳定高效运行;最后,通过仿真算例验证了所设计的DC/DC变换器拓扑的优越性和控制策略的有效性。Along with the increase of their generation capacities and offshore distances,wind farms with DC collection and avoiding overvoltage have been aroused more and more attention.As the mainstream model of the offshore wind power exploitation,the direct-drive wind turbine realizes DC interconnection through the design of the DC/DC converter.Firstly,a scheme for dual three-level soft switching DC/DC converter is proposed considering the demand of the DC wind turbine,which effectively reduces the converter volume and its switching losses.Secondly,through a detailed analysis of the working principle of the sub-converter,a method for designing the important parameters of the sub-converter is given.Then,the control strategies in both the normal and the fault periods are given based on the control objectives of the DC/DC converter,ensuring the safe,stable and efficient operation of the turbine.Finally,the superiority of DC/DC converter topology and the effectiveness of control strategy are verified by simulation results.

关 键 词：直流海上风电场 直流输出型直驱风机 全桥三电平DC/DC变换器 软开关 电流断续模式 

分 类 号：TM614[电气工程—电力系统及自动化]