瞬时功率聚合传输的低电容值大功率级联型风力发电系统  

Low-capacitance High-power Cascaded Wind Turbine System With Instantaneous Power Convergence and Transition

作　　者：张永磊[1] 朱朋 原熙博[1] 彭新 李炎[1] 伍小杰[1] ZHANG Yonglei;ZHU Peng;YUAN Xibo;PENG Xin;LI Yan;WU Xiaojie(School of Electrical Engineering,China University of Mining and Technology,Xuzhou 221008,Jiangsu Province,China)

机构地区：[1]中国矿业大学电气工程学院,江苏省徐州市221008

出　　处：《电网技术》2022年第7期2759-2767,共9页Power System Technology

基　　金：国家自然科学基金项目(52107218,52177201);中国博士后科学基金项目(2019M652004)。

摘　　要：随着海上风电机组单机容量的不断增加,传统低压两电平背靠背变流器存在额定电流过大、解揽困难等问题,难以满足10~20MW大型海上风电机组功率变换需求。为此,提出了一种基于瞬时功率聚合传输的中压大容量级联H桥风电变流器拓扑结构。该拓扑利用四端口DC/DC变换器进行电气隔离。并给出了一种基于瞬时功率聚合传输的控制方法,将级联H桥三相H桥单元的低频脉动功率进行聚合传输,消除级联H桥的直流侧低频脉动电压。相比于常规级联H桥风电变流器,所提拓扑不需要多绕组工频变压器隔离,并且可以大幅降低所需的低频滤波电容,具有功率密度高、成本低、可靠性高(直流滤波电容)的优势。最后搭建了小功率模拟实验平台,验证了所提拓扑及控制策略的有效性。With the increase of the unit capacities of offshore wind turbines,the conventional low-voltage two-level back-to-back converters suffers from the problems like overlarge current,difficulties in twisting cables,and so on,which is not suitable for the demands of the 10~20MW large offshore wind turbines.This paper proposes a medium-voltage high-power cascaded H-bridge wind power converter topology based on the instantaneous power aggregation and transmission.A four-port isolated DC/DC converter is used at each cascaded stage to converge and transmit the instantaneous power of the three-phase H-bridge in this stage,where the low-frequency pulsating power of the three-phase H-bridge cell can be mutual cancellation thereby solving the low-frequency voltage pulsation problem in the cascaded H-bridge.Compared with the conventional cascaded H-bridge wind power converters,the proposed topology has significant advantages such as higher power density,lower costs and higher reliability by operating the multi-winding low-frequency transformers and reducing greatly the required low-frequency filter capacitors in each unit,especially for the filter capacitors.A low-power experiment prototype is built to verify the proposed topology and control approach.

关 键 词：风力发电 低频脉动功率 级联H桥 低电容值 

分 类 号：TM614[电气工程—电力系统及自动化]