风电并网逆变器的双闭环自抗扰控制策略研究

Research on Double Closed⁃loop Active Disturbance Rejection Control Strategy of Wind Power Grid⁃connected Inverter

为提高风电并网逆变器在同步旋转坐标系下dq轴电流的解耦效果及电网故障下母线电压的抗扰性能,提出一种新线性自抗扰控制(Linear Active Disturbance Rejection Control,LADRC)的双闭环结构。根据风电并网逆变器的数学模型,得到传统的基于PI控制的电压电流双闭环系统,分析电流内环控制在电流解耦中存在的局限性。将LADRC技术用于内环以削弱dq轴电流间的耦合,外环应用LADRC技术提高系统的抗扰性能。通过仿真对所提出的新型双闭环结构的控制性能进行验证,结果表明该控制结构在解耦效果、抗扰性能等方面均优于传统的PI双闭环结构。对大型风电机组并网的稳定性控制具有实际意义。

In order to improve the decoupling effect of the dq axis current of wind power grid⁃connected inverters in the synchronous rotating coordinate system and the disturbance rejection performance of the bus voltage under grid faults,a new linear active disturbance rejection control(LADRC)double closed loop structure was proposed.According to the mathematical model of the wind power grid⁃connected inverter,the traditional voltage and current double closed⁃loop system based on PI control was obtained,and the limitations of current inner loop control in current decoupling were analyzed.The LADRC technique was used in the inner loop to weaken the coupling between the d⁃axis and q⁃axis currents,and LADRC technology was used in the outer loop to improve the anti⁃interference performance of the system.The control performance of the proposed new double closed⁃loop structure was verified by simulation.The results show that the control structure is superior to the traditional PI double closed⁃loop structure in terms of decoupling effect and anti⁃interference performance,which has actual significance for the stability control of large⁃scale wind turbine grid connection.