Digital PID Controller Design of Electromagnetic Suspension (EMS) System


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This paper presents the digital PID controller design of magnetic levitation application. The highly nonlinear of electromagnetic suspension (EMS) system is hardly and limited the 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 at a nominal operating point. Such a linear system, digital PID controller is designed for controlling the EMS plant. The system stability is validated by experiment methods. From the results, the reference of air gap position can be tracked with the desired nominal operating air gap position control as shown in practical manner.



Edited by:

Liangzhong Jiang




A. Suebsomran, "Digital PID Controller Design of Electromagnetic Suspension (EMS) System", Advanced Materials Research, Vol. 590, pp. 165-172, 2012

Online since:

November 2012





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