The Open Automation and Control Systems Journal

2014, 6 : 1-8
Published online 2014 March 07. DOI: 10.2174/1874444301406010001
Publisher ID: TOAUTOCJ-6-1

Optimal Control of Electromagnetic Suspension EMS System

Anan Suebsomran
Department of Teacher Training in Mechanical Engineering, King Mongkut’s University of Technology North Bangkok, 1518 Pibulsongkram Rd., Bagsue, 10800, Bangkok, Thailand.

ABSTRACT

This paper presents the controller design of magnetic levitation application. The highly nonlinear electromagnetic suspension EMS system is hard and limited system control subjected to prescribed stability of system. Due to the nonlinear dynamics of system, the linearization of the nonlinear EMS plant is described by linear model. An attraction force about the prescribed nominal operating point of current and air gap positioning is chosen for linearization by a nominal operating point. Optimal control is applied for controlling nonlinear dynamics of EMS plant. Linear quadratic regulator (LQR) controller applies for this control objective. The system stability is proofed by using Lyapunov’s method. From the results the reference of air gap position can be tracked with the desired nominal operating control as shown in simulation and practical manner.

Keywords:

Electromagnetic suspension EMS system, linear quadratic regulator (LQR), linearization.