Sensorless non-linear position-stabilising control for magnetic levitation systems

Abstract

This study presents a solution to the position stabilisation problem for non-linear magnetic levitation systems using the only position measurement. This considers parameter and load variations without the use of current and velocity feedback. The features are given as follows: (i) the removal of current and velocity feedback by the proposed first-order state estimators without system parameters, (ii) securing of improved closed-loop robustness from the combination of active damping and specified feedback gain with the closed-loop system order reduced to 1 and (iii) proof of performance recovery and offset-free in the absence of regulation error integral actions. The numerical simulations verify the performance and robustness improvements through realistic scenarios.