Model-Free Active Disturbance Rejection Control Algorithm

The model-free active disturbance rejection control (ADRC) algorithm represents an advanced control strategy whose core principle involves treating the network components and controlled plant as an integrated system for control purposes, eliminating the need for precise mathematical models. This algorithm employs an extended state observer (ESO) to monitor system dynamics in real-time, including internal parameter variations and external disturbances, thereby achieving accurate estimation and compensation of system states. In code implementation, the ESO typically uses difference equations to estimate total disturbances by extending the system state space.

Compared to traditional model-dependent control methods, the model-free ADRC algorithm offers several advantages: 1) Avoids control performance degradation caused by modeling errors; 2) Exhibits strong robustness against system time-varying characteristics and unknown disturbances; 3) Dynamically adjusts control outputs through online observation mechanisms, making it particularly suitable for complex scenarios with network delays or parameter drift. The algorithm implementation generally consists of three key components: a tracking differentiator (TD) for arranging transient processes, an extended state observer (ESO) for consolidating disturbances, and a nonlinear state error feedback (NLSEF) law for generating control signals. In practical coding, these components can be implemented using discrete difference equations with parameter tuning for bandwidth normalization.

This algorithm has demonstrated significant advantages in domains with strong nonlinear characteristics such as electromechanical systems and power electronics. Future research should explore its integration with adaptive algorithms in industrial internet scenarios, potentially involving code-level modifications for parameter self-tuning capabilities and disturbance estimation enhancements.