Active disturbance rejection control of large-scale uncertain industrial processes: A practical tuning case in thermal power units

Active disturbance rejection control (ADRC) shows great potential in industrial process control. However, for processes dominated by low-frequency dynamics, real-time compensation in the traditional integrator-chain structure is difficult to guarantee. To this end, this paper studies ADRC in the perspective of low-frequency approximation. The proposed method directly accounts for untimely compensation, and addresses the discrepancies between the desired and actual closed-loop dynamics found in traditional methods through a new controller parameters tuning rule. First, the equivalent plant of ADRC in low-frequency band is derived. A tuning rule integrated with the process dynamics is derived dependent on the desired closed-loop dynamic. A field tests friendly tuning procedure is given. Finally, simulation studies based on fair comparison and field application test verify the great efficacy of proposed method.