Reduced-order active disturbance rejection control for induction motors

In this paper a novel control strategy, the reduced-order active disturbance rejection control (RADRC) with reduced-order extended state observer (RESO) is applied for induction motor control. In the RADRC framework, the disturbance and unmodeled dynamics associated with induction motors are treated as an additional state variable, which is then estimated and compensated for in real time. This reduces a normally complex, time-varying, nonlinear, and uncertain dynamic process to an approximately linear, time-invariant, cascade integral form, where a simple proportional plus derivative controller suffices. Simulation results demonstrate excellent tracking, disturbance rejection, and robustness performance of the RADRC in the absence of an accurate mathematical model of the induction motor.