Reduced-order method for magnetic levitation system

For a magnetic levitation system regulated by voltage, time optimal control algorithm was designed to increase current response speed and constraints of system hardware to current response were derived. Variable structure control strategy correspond to tracking error was implemented to reach ideal current with high precision. The control voltage can be calculated based on coil parameters identified through online identification to maintain the setting current. Using the method, equivalent fine properties of employing voltage control can be achieved compared with current control. Consequently, analysis of control system is simplified and robustness with coil parameters is improved. The algorithm is demonstrated effectively by both current response and levitation experiment of magnetic levitation ball and it also can be extended to other current regulating applications.