Design of a 2-DOF Control and Disturbance Estimator for a Magnetic Levitation System


  • A. Pati Department of Electrical Engineering, Motilal Nehru National Institute of Technology (MNNIT), India
  • V. C. Pal Department of Electrical Engineering, Motilal Nehru National Institute of Technology (MNNIT), India
  • R. Negi Department of Electrical Engineering, Motilal Nehru National Institute of Technology (MNNIT), India
Volume: 7 | Issue: 1 | Pages: 1369-1376 | February 2017 |


This work proposes a systematic two-degree freedom control scheme to improve the reference input tracking and load disturbance rejection for an unstable magnetic levitation system. The proposed control strategy is a two-step design process. Firstly, a proportional derivative controller is introduced purposely to get the desired set-point response of the magnetic levitation system and then, an integral square error (ISE) performance specification is used for designing a set-point tracking controller. Secondly, a disturbance estimator is designed using the desired closed loop complimentary sensitivity function for the rejection of load disturbances. This leads to the decoupling of the nominal set-point response from the load disturbance response similar to an open loop control manner. Thus, it is convenient to optimize both controllers simultaneously as well as separately. The effectiveness of the proposed control strategy is validated through simulation.


Maglev System, PID, Maclaurin Series, Disturbance Estimator


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How to Cite

A. Pati, V. C. Pal, and R. Negi, “Design of a 2-DOF Control and Disturbance Estimator for a Magnetic Levitation System”, Eng. Technol. Appl. Sci. Res., vol. 7, no. 1, pp. 1369–1376, Feb. 2017.


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