Robust Feedback Control Analysis of Magnetic Levitation System

Abstract: The Magnetic Levitation System is one of the important benchmark laboratory models for the design and analysis of feedback control systems. Robust feedback control for magnetic levitation systems is considered problematic due to the parametric uncertainties in mass, strong disturbance forces between the magnets and noise effects inflowing from sensor and input channels. Therefore robustness is a key issue in designing a control system for a magnetic levitation as the models are never 100 percent accurate and the uncertainties in the model must be accounted. In this paper, H1 robust control is investigated to bring the magnetic levitation system in a stable region by keeping a magnetic ball suspended in the air in the presence of uncertainties. The paper first presents the complete non-linear and linear mathematical models and then it adopts the mixed sensitivity design method for H1 controller synthesis. The simulation results show that the designed controller meets robustness against model uncertainties and permits very precise positioning of the levitated object