Control strategy of LCL grid-connected inverter based on reduced-order sliding mode linear active disturbance rejection
ZHU Longji
XIE Enchao
Abstract：Aiming at the shortcomings of the traditional inductor-capacitor-inductor(LCL)filtering method for grid-connected inverters,such as poor grid current quality,weak dynamic performance,and low disturbance re-jection capability,a reduced-order sliding-mode linear active disturbance rejection control(SM-LADRC)strategy is proposed.This method simplifies the parameter tuning process by employing a reduced-order linear extended state observer(LESO)to accurately estimate and compensate for both internal and external disturb-ances within the system.Meanwhile,the sliding mode control theory is integrated to formulate a sliding-mode state error feedback control law,taking advantage of its rapid convergence characteristics to enhance the dy-namic response capability of the system.Simulation results demonstrate that,in comparison to traditional linear active disturbance rejection control(LADRC),the proposed strategy significantly reduces the total harmonic distortion(THD)of the grid current to below 0.64%,shortens the dynamic response time to 0.008 seconds,and decreases the current deviation by 47%.Moreover,it maintains high robustness under complex operating conditions such as grid voltage fluctuations and harmonic injection.Therefore,the reduced-order SM-LADRC strategy effectively enhances the system's disturbance rejection capability and grid current quality,lowers system costs,and exhibits excellent dynamic performance.This approach provides a novel solution for the con-trol of LCL-type grid-connected inverters.
Keywords：sliding mode controllinear active disturbance rejection controlgrid-connected inverterorder re-ductionharmonics
Publication Date：2025-12-30
Online Publishing Date：2025-12-19(First online date of this platform, not the publication date of the document)
Pages：7( 60-66 )