Abstract：Aiming at the problem that the photovoltaic grid-connected inverter system operates under multiple

disturbances，an linear active disturbance rejection control（LADRC）grid-connected strategy combined with

photovoltaic system was proposed. Firstly，the dynamic process of PV grid-connected system was analyzed and

modeled，and the LADRC-PM structure was designed according to the model characteristics of the photovoltaic

system，further improving the speed on the basis of the classical structure. And then，the structure was introduced on the basis of the double closed-loop control framework，so that the system could compensate the disturbance through the feedforward way to enhance the system ability to suppress the uncertainty. Furthermore，the mathematical model of the proposed control strategy was dynamically analyzed using frequency domain analysis method，and its engineering stability，tracking convergence，and disturbance rejection superiority were theoretically verified，and the guidance of adjusting some parameters was given. Finally，the advantages of LADRC-PM control strategy was verified by the Matlab/Simulink simulation in various working conditions.

      Key words：photovoltaic grid-connected；first-order active disturbance rejection control（ADRC）；model

analysis and combination；multi-condition transient test