海上风电场三电平VSC-HVDC系统仿真研究

随着土地资源紧缺和海上风电成本的不断降低,海上风电开发与建设受到各国重视,且随着海上风电场规模的扩大,急需采用柔性直流输电变流器装置.这里研究了海上风电场柔性直流输电变流器拓扑结构及控制方式,其中,主电路采用中点箝位式三电平结构,通过建立该结构的等效数学模型,根据空间矢量调制算法,检测交流侧电流方向以及直流侧电容电压,...

Simulation of Offshore Wind Farms Three-level VSC-HVDC System

With the shortage of land and the declining cost of wind power generation on the sea,offshore wind farm grows popular in more and more countries.This paper studies topology structure and control strategies of the converter.The main circuit adopts a three-level neutral point clamped structure whose equivalent mathematical model has been established.According to the space vector modulation algorithm,by testing the AC current direction and DC side capaci-tor voltage,the method of midpoint voltage balance control to guarantee the balance of capacitor voltage is given.The control system adoptes double closed loop vector control strategy,in which both of converters work in step with DC voltage controlled by wind farm lateral and active power controlled by grid side.Inner loop used current feed-forward decoupling method to realize active power and reactive power independently control.Finally,simulation model is set up in Matlab,results show the topological structure advantageous and control strategies correct.