自抗扰控制器在动态电压恢复器中的应用

为了提高动态电压恢复器(dynamic voltage restorer,DVR)系统的动态性能和鲁棒性,根据自抗扰控制器(ADRC)的原理设计了DVR自抗扰控制方案.自抗扰控制器的设计不需要精确的DVR参数和数学模型,将电网电压和负载电流视为系统的未知干扰,用扩张状态观测器对未知扰动进行观测,然后利用非线性反馈控制律进行补偿,使系统的控制律今与系统的给定输入和输出有关,减少了控制过程中的检测量,将复杂的控制过程加以简化.仿真和实验表明,自抗扰控制器对系统模型的不确定性和外扰具有较强的适应性和鲁棒性,控制系统具有优良的动态性能.

Active disturbance rejection controller for dynamic voltage restorer

Dynamic voltage restorer(DVR) is a complex nonlinear system that conventional PID control and modern control theories cannot assure a satisfactory behavior.In order to achieve high dynamic performance and robustness of control system,a new strategy for DVR was presented by using auto-disturbance rejection controller(ADRC).The ADRC controller was designed without accurate DVR parameters and model.The source voltage and load current were treated as system disturbances and were estimated by using the expending state observer(ESO).Then the disturbances were compensated by the nonlinear state error feedback control law(NLSEF).The control law has only relationship with the reference and the output,so the control was simplified with fewer variables to be detected.The simulation and experiment results show that the controllers ensure very good robustness and adaptability under modeling uncertainty and external disturbances,and produce good dynamic performance.