Cross-coupling-based fuzzy active disturbance rejection control for dual-path snubbing unit lifting system

The performance of a fuzzy linear active disturbance rejection controller applied within a hydraulic lifting system under different operating conditions is systematically investigated in this study. It is demonstrated through experimental results that the position tracking accuracy and synchronization performance of the lifting system are significantly enhanced by the fuzzy linear active disturbance rejection controller in comparison to conventional PID controllers. Under both light load and heavy-load conditions, the fuzzy linear active disturbance rejection controller substantially reduces the maximum synchronization error and demonstrates higher stability during the lifting maintenance phase. Moreover, when it comes to resisting external disturbances, the controller exhibits superior robustness, effectively reducing both the frequency and magnitude of oscillations. The experiments also highlight that the controller's optimized root-mean-square synchronization error is reduced by 50.5% to 87.5% compared to the pre-optimization values, underscoring its substantial improvement in disturbance rejection performance. Therefore, the study unequivocally establishes that the fuzzy active disturbance rejection controller offers significant performance advantages within hydraulic lifting systems. It maintains a high level of synchronization performance and stability, regardless of load variations or external disturbances, thus presenting a practical and valuable control strategy for pressurized lifting operations.