Disturbance suppression enhancement scheme based on dual correction linear active disturbance rejection control for load-side power interface in microgrid

It is difficult to maintain high-quality power output under various interferences when the load-side converter with a conventional controller is connected to the microgrid. To this end, a linear active disturbance rejection control with dual correction link (LADRC-2CL) is purposed to deal with this problem. In this scheme, the accuracy correction link is serially connected between the disturbance observation output and the control law, thereby optimizing the offset of disturbance estimation. On this basis, rate correction link was appended to the conventional extended state observer (CLESO) framework as an additional composition, so as to improve rate of convergence for disturbance observation. Then, the stability and tracking performance are analyzed theoretically. Compared with the conventional control scheme, the plant can result in a faster and smoother adjustment process by the investigated strategy, thereby improving dynamic performance. Additionally, influence of parameters on performance were analyzed, which can guide the tuning of control parameters. Finally, comparative experiments are conducted on a 40-kW test platform to verify the effectiveness of the proposed control approach.