IJCAS

This paper presents an adaptive feedback linearization control scheme for induction motors using stator fluxes. By using stator fluxes as states, overparameterization is prevented and control inputs can be determined straightforwardly unlike in existing schemes. This approach leads to the decrease of the relative degree for the flux modulus and thus yields a simpler control algorithm than the prior results. In this paper, adaptation schemes are suggested to compensate for the variations of stator resistance, rotor resistance and load torque. In particular, the adaptation to the variation of stator resistance with a feedback linearization control is a new trial. In addition, to improve the convergence of rotor resistance estimation, the differences between stator currents and its estimates are used for the parameter adaptation. The simulations show that torque and flux are controlled independently and that the estimates of stator resistance, rotor resistance, and load torque converge to their true values. Actual experiments on a 3.7kw induction motor verify the effectiveness of the proposed method.

Keywords: feedback linearization, adaptive control, parameter estimation, induction motor