一种基于二重移相变换的大容量海上直流风机及控制技术  

One Kind of Large-scale DC Wind Turbine and Its Control Technology Based on Dual Phase-shift Power Conversion

作　　者：刘其辉 洪诚程 樊双婕 袁振华 田鑫 LIU Qihui;HONG Chengcheng;FAN Shuangjie;YUAN Zhenhua;TIAN Xin(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,Jinan 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：《中国电机工程学报》2023年第2期507-518,共12页Proceedings of the CSEE

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：海上风电场采取直流汇集方案,相较于交流汇集无需笨重的工频变压器,避免交流电缆带来的过电压问题,系统效率更高。直驱风机作为海上风电场的主流机型,通过直流转直流电源(DC/DC)变换器的设计和机组控制策略的改进可实现直流并网。首先依据机组直流并网需求提出一种二重化移相三电平DC/DC变换器方案,优化设计双占空比调制策略,分析子变换器功率传输特性;其次建立直流风机的控制策略,实现机组正常工作时最大风能跟踪目标,并且保障故障期间机组的安全稳定运行;最后通过仿真算例验证所设计DC/DC变换器拓扑的可行性和直流输出型直驱风机控制策略的有效性。Compared with AC offshore wind farm,the offshore wind farm with DC collection scheme does not require heavy line frequency transformers and avoids the problem of overvoltage caused by the charging power of AC cables,which has higher efficiency.As the main type of offshore wind turbine,a directly-driven wind turbine can realize connection with DC grid through the design of the DC/DC converter and the improvement of the turbine control strategy.First,a dual phase-shifted three-level DC/DC converter is proposed according to the demand of the DC wind turbine(DCWT).An optimized dual duty cycle modulation strategy is designed and the power transmission characteristics of the sub-converter is analyzed.Secondly,the control strategy of the DCWT is designed to achieve MPPT in a normal period and ensure the stable operation of DCWT in a fault period.At last,the feasibility of DC/DC converter topology and the effectiveness of DCWT 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 二重化三电平变换器 双占空比调制策略 

分 类 号：TM614[电气工程—电力系统及自动化]