Application of an auto-disturbances-rejection controller in variable-frequency speed regulation systems

In order to solve the poor robustness of parameters in a vector control system, a new kind of control scheme for induction-motor variable-frequency speed regulation systems was proposed based on the theory of auto-disturbances-rejection control (ADRC). In the control scheme, the change in rotor time constant was regarded as the inner disturbance of the flux subsystem, the effect of the change in rotor flux linkage amplitude and that of load as the inner and exterior disturbances of the rotate speed subsystem respectively, and the extended state of an extended state observer (ES()) was used for estimation and compensation. The control scheme can solve such problems as the effect of time-varying parameter on the decoupling performance of a vector control system and the contradiction between speediness and stability in common vector control systems. Simulated results indicated the rationality and validity of the scheme abovementioned.