자기베어링 시스템의 동정과 제어에 관한 연구

Abstract

The magnetic bearing system is widely applied to the suspension system of the rotors on the rotary machineries at the special condition, because this system has many advantages such as less mechanical friction, low heat generation, no noise, no lubrication and so on. The magnetic bearing system is inherently an unstable system, so this system needs the controller to stabilize it. Many studies are devoted to the design of controllers which make the system stabilize and the analysis which finds the system's dynamic characteristics. This study is concerned about the design and the control for the magnetic bearing system. The current amplifier's circuit is designed. And the electromagnet, the displacement sensor, the levitated object, the base, the bracket and housing are designed. After assembling the magnetic bearing system, the mathematical transfer function is calculated. The unkn - ⅳ - own parameters are identified by the real coded genetic algorithm. The validity of the PID controller is verified by the response experiments for the assembled magnetic bearing system. The process of the study is followed. The chapter 1 is concerned about the background for the magnet bearing system and the list of the other studies performed before about this system. And it also is talked about the necessity for this study. The chapter 2 is considered about the design problem of the current amplifier's circuit to drive the magnetic bearing. The current amplifier is selected to design the amplifier's circuit. And the parameter's value of the circuit's components are computed by the real coded genetic algorithm to satisfy the output condition that we want. The current amplifier's circuit is assembled by the standardized goods that are selected with the result of computing. The chapter 3 is concerned about the manufacturing for the magnetic bearing system. The magnetic bearing's coil is selected. And the magnetic bearing's material also is selected. The iron core is designed. And the journal bearing, the magnetic bearing's base, bracket and housing are designed. After assembling the components of the magnetic bearing system, the mathematical transfer function is calculated. The chapter 4 is considered that identification for the magnetic bearing system. The magnetic bearing system's stability is calculated by Routh array. - ⅴ - And the PID controller is selected to stabilized the system. The system's parameter is identified by the real coded genetic algorithm. The chapter 5 is concerned about the response experiment. The magnetic bearing system is divide into two type that control signal is separated or not. These magnetic bearing system are used the same PID controller and are taken the response experiment of the reference input change and the mass disturbance. The robustness of the magnetic bearing system is computed by the frequency response. The chapter 6 is concerned about the conclusion. The results of each chapter are remind in this chapter.