基于自抗扰控制的单相光伏并网逆变控制器设计

Controller Design of Single Phase PV Grid-connected Inverter Based on Active Disturbance Rejection Control

传统的双环PI控制无法满足LCL并网逆变器电流谐波,输出电压扰动大;线性自抗扰技术可以通过线性扩张状态观测器和线性控制律对总扰动进行实时估计和补偿,大大提高并网逆变控制器的性能.为提高系统输出对电网电压扰动的抑制能力和系统的起动性能,引入电网电压前馈控制策略,提出基于自抗扰控制的电网电压前馈控制策略,采用MATLAB软件进行仿真.仿真结果表明,基于线性自抗扰控制下的单相光伏并网控制系统可实现对入网电流的无静差跟踪,提高了系统抑制电网电压扰动的能力,入网电流的总谐波失真小.

The traditional double loop PI control can not satisfy the large current harmonic and output voltage disturbance of LCL grid connected inverter,linear active disturbance rejection technology can estimate and compensate the total disturbance in real time through linear extended state observer and linear control law,which greatly improves the performance of grid connected inverse variable controller.In addition,in order to improve the ability of the system output to suppress the grid voltage disturbance and the starting performance of the system,the grid voltage feedforward control strategy is introduced.Therefore,this paper proposes the grid voltage feedforward control strategy based on active disturbance rejection control.MATLAB software is used to simulate and verify that the single-phase photovoltaic grid connected control system based on linear active disturbance rejection control can realize no steady-state error tracking of the incoming current,which improves the ability of the system to suppress the grid voltage disturbance,the total harmonic distortion of the incoming current is small.