An ADRC based multiple activated anti-windup design

A multiple activated anti-windup compensated algorithm for Active Disturbance Rejection Control (ADRC) mechanism is proposed in this paper. This paradigm extends the multi-activated anti-windup scheme to the active disturbance rejection mechanism, to deal with the input saturation nonlinearity and meanwhile reject the disturbance automatically by using Extended State Observer (ESO). The output of anti-windup compensator is treated as a part of unknown disturbances and is introduced into the ESO, which can online observe both internal and external disturbances (parameter uncertainties and model mismatches). The controller input is yielded by using a nonlinear feedback combination, and it is used to compensate the integrator windup caused by the saturation nonlinearity element. On the other hand, in order to determine the parameters of the ESO and the anti-windup compensator feedback gain, the L2 gain design method is considered. The effectiveness and the robustness against model and parameter uncertainties of the proposed method is verified by an example of the seeker platform.