基于自抗扰控制的网络构建及其协调控制研究

Research on network construction and coordinated control based on enhanced anti-disturbance ability of microgrid

为解决直流微电网中分布式电源输出功率波动、负载突变以及不确定性外界干扰对母线电压造成的不利影响,结合智能PI控制器和自抗扰控制(active disturbance rejection control, ADRC)技术的优势,设计了一种智能自抗扰控制器(intelligent active disturbance rejection control, IADRC)应用于电压外环,有效地增强了系统的鲁棒性。此外,为了提高系统对扰动的估计精度,降低传统线性扩张状态观测器对扰动的估计误差,提出了一种改进线性自抗扰控制(improved linear active disturbance rejection control, ILADRC)策略应用于电流内环,该策略通过构造级联线性扩张状态观测器(linear expansion state observer, LESO),处理扰动估计误差中的稳态偏移,实现了对扰动状态的精确重构。最后,利用MATLAB/Simulink软件与常规PI控制器和传统自抗扰控制器(tradition active disturbance rejection control, TADRC)进行仿真比较。仿真结果表明,在外界不确定因素的干扰下,设计的控制器和提出的控制策略使得直流母线电压超调量更小,稳定时间更短,有效提高系统的动态响应性能和抗干扰能力。

In order to solve the adverse effects of distributed power output power fluctuation,load sudden change and uncertain external interference on the bus voltage in DC microgrid,this paper combines the advantages of intelligent PI controller and automatic disturbance rejection controller(ADRC)to design an intelligent automatic disturbance rejection controller(IADRC),which effectively enhances the robustness of the system.In addition,in order to improve the estimation accuracy of the system for disturbance and reduce the estimation error of the traditional linear expansion state observer,an improved linear automatic disturbance rejection control(ILADRC)strategy is proposed,which realizes the accurate reconstruction of the disturbance state by constructing a cascaded linear expansion state observer(LESO)to process the steady-state offset in the disturbance estimation error.Finally,MATLAB/Simulink software is used to simulate and compare with conventional PI controllers and conventional automatic disturbance rejection controllers(TADRC).The simulation results show that under the interference of external uncertainties,the controller designed and the proposed control strategy make the DC link voltage overshoot smaller,the stability time shorter,and effectively improve the dynamic response performance and anti-interference ability of the system.