Adaptive Active Disturbance Rejection Control Design For Uncertain Input Gain

In the well-known active disturbance rejection control (ADRC) scheme, the input gain b0 is a critical parameter for control system design. However, it is difficult to obtain the accurate b0 information due to the coupling effect caused by the external disturbance. In this paper, we propose an adaptive scheme for b0 online tuning when the uncertainties occur. The tracking error between a reference model and control system is adopted to generate the adaptive b0 tuning. The stability is proved by Lyapunov theory, and an energy-dependent parameter is used to provide a normalizing adaptation such that the adaptive system can operate with a wide range of external inputs. Finally, two simulation examples are used to illustrate the effectiveness of the proposed method.