Robust current and speed controllers of the frequency-controlled induction electric drive

Abstract

An induction frequency-controller electric drive with the vector control is a multiply and nonlinear control object. Equations that describe the object include variable parameters. In addition, the drive is affected by some external disturbances. Traditional methods of the representation of the control object do not make it possible to take into account these effects thus complicating the analysis of static and dynamic properties of the resulting system under external and internal disturbances. We propose to use the interval transfer functions of the object with their constituent relative variations, which makes it possible to analyze the effect of parametric perturbations. Robust controllers of phase-current projections and speed are synthesized based on polynomial methods. Analysis of these controllers using interval models showed that they really provide a low sensitivity to perturbations. Mathematical modeling and experimental studies confirmed the possibility of research based on interval transfer functions, as well as the effectiveness of fabricated robust controllers.