基于降阶扩张状态观测器的逆变系统重复控制设计

针对具有参数不确定性和负载扰动的单相全桥LC型逆变器，提出一种基于降阶扩张状态观测器（ROESO）的重复控制系统设计方法。首先，根据电路定理推导出逆变器的数学模型，并针对该模型利用系统可测量输出电压构造ROESO，用以实时估计由系统参数不确定性和外部干扰组成的总扰动。在此基础上，嵌入改进型重复控制器，构造复合重复控制规律，实现对扰动的有效抑制和对周期性参考输入的高精度跟踪。然后，利用小增益定理推导出系统的全局稳定性条件，并给出控制器参数整定方法和系统设计步骤。最后，通过仿真验证所提方法的有效性和优越性。

Repetitive-control Design of an Inverter System Based on a Reduced-order Extended-state Observer

A method of designing a repetitive-control system based on a reduced-order extended-state observer (ROESO) is presented for a single-phase full-bridge LC-type inverter subject to parameter perturbation and load disturbances. First, the mathematical model of the inverter is derived from the circuit theorem. An ROESO is constructed by making use of the measurable output voltage of the system to estimate the total disturbance, including the parameter uncertainty and external load disturbance in a real-time fashion. Next, a plug-in modified repetitive controller is inserted into the closed-loop system and based on the disturbance estimate, a composite control law is constituted, which effectively attenuates the influence of the total disturbance on the output of the system and ensures the high-accuracy tracking of the periodic reference input. Then, the global stability condition of the closed-loop system is established using the small-gain theorem. The parameter regulation method and design procedure of the system are given. Finally, simulation results demonstrate the validity and superiorities of the method.