基于LADRC的双馈风机与SVG协调控制的并网系统研究

Research on grid-connected system with coordinated control of doubly-fed induction generator and SVG based on LADRC

为了解决双馈风机(doubly fed induction generator,DFIG)在并网或运行时给电网带来的稳定性问题,提出了静止无功发生器(static var generator,SVG)与DFIG协同补偿无功的方法,并在此基础上通过线性自抗扰控制(linear active disturbance rejection control,LADRC)代替传统的PI控制来控制变流器,以及加装超级电容储能对DFIG的变流器直流侧控制进行优化。最后结合风电场的实际情况,在MATLAB中搭建了使用LADRC的含超级电容的双馈风机并网模型,并对其并网时的交直流波动以及无功功率的传输进行了仿真分析,实验结果验证了该控制策略可以提高双馈风机稳定运行的能力,解决功率波动时变流器交直流侧功率不平衡的问题,与SVG的协同控制策略可以提高系统的低电压穿越能力,提高了整个风力发电系统的稳定性。

To address the stability issues caused by doubly fed induction generator(DFIG)during grid connection or operation,this paper proposes a coordinated reactive power compensation method utilizing static var generator(SVG)in conjunction with DFIG.Furthermore,the traditional PI control for converters is replaced with linear active disturbance rejection control(LADRC),and supercapacitors are installed to optimize the DC-side control of DFIG converters.Finally,based on the actual conditions of wind farms,a grid-connected DFIG model integrated with supercapacitors and utilizing LADRC is established in MATLAB.A simulation analysis is conducted on the AC-DC fluctuations and reactive power transmission during grid connection.The experimental results verify that this control strategy can enhance the stable operation of DFIG,resolve the issue of AC-DC side power imbalance in converters during power fluctuations,and the coordinated control strategy with SVG can improve the system′s low-voltage ride-through capability,thereby enhancing the overall stability of the wind power generation system.