Dual LQG-PID control of a highly nonlinear magnetic levitation system

Abstract

A study of one-dimensional position control of a light iron ball levitated by one electromagnet is proposed in this work. The vertical position of the ball is the target of the proposed control strategy. It is assumed that the position measurement of the ball is inaccessible and thus, estimates of the position are utilized as the feedback signal to the controller. Control of the ball's position is carried out using LQG-based controller with the objective of manipulating the electromagnet current to drive the ball to steady state with minimal error. The integrity of the controller as well as accuracy of the system's model is evaluated via simulation.