Papers by Keyword: Active Magnetic Bearing System

Abstract: In this paper, a new integral sliding mode control scheme is designed for the 3-pole active magnetic bearing system. First, a new integral sliding surface is designed such that the 3-pole active magnetic bearing system in the sliding mode is asymptotically stable under certain conditions. Then, an adaptive controller is designed to solve the unknown upper bound of matched uncertainty and guarantee the reachability of the integral sliding surface. Finally, the performance of the proposed integral sliding mode controller is applied to 3-pole active magnetic bearing system to demonstrate the efficacy of the proposed method.

Abstract: Based on the principle of axial active magnetic bearing rotor-system with single degree of freedom, magnetic rotor-system vibration mode was described. A 3D finite element model of active magnetic bearing rotor-system was established by ANSYS11. Initial six order natural frequencies and vibration mode were calculated by the module of modal analysis of ANSYS11, and compared with the results of system identification. Analysis shows that there was a certain difference between the results, but the difference was small. The analysis result indicates that it is an effective method to apply FEA in the design of the active magnetic bearing. It provided the foundation for structure optimal design of the system and theoretical basis for flexible system design.

Abstract: The paper presents the sensitivity and stability margin analyses of the flexible rotor supported by active magnetic bearings (AMBs) with the robust optimal vibrations control. The modal representation of the rotor finite element model (FEM) is investigated. Then, the open-loop system of the AMBs flexible rotor is established and critical speed analysis due to variation of bearing stiffness is performed. For the open-loop setup, the non-collocation effect of displacement sensors and magnetic actuators due to control stability problem is considered. The frequency mode analysis of the collocation and non-collocation system is presented. Next, the -synthesis control of 4-DOF AMBs rotor is investigated. The design process of -controllers, which cover uncertainty design and performance shape by chosen weighting function is shortly described. Then, the sensitivity function is calculated and used to evaluate the AMBs rotor stability margin for the -control and the PID control. The performance of the -controller are verified in experimental tests.