本文旨在研製無機械接觸式磁軸承馬達之控制系統。磁軸承馬達使用磁力將轉軸控制於氣隙中心，有效減少馬達運轉時產生的摩擦損耗。本文磁軸承馬達結構為12 槽8 極雙繞組結構，分別為馬達驅動繞組及磁軸承繞組。馬達驅動繞組搭配電磁轉矩控制策略，控制磁軸承馬達輸出電磁轉矩。磁軸承繞組搭配間隙控制策略，控制磁軸承馬達轉軸在氣隙中的位置，使轉軸於原點運轉。間隙控制使用渦電流式間隙感測裝置PU-14，偵測X 軸、Y 軸徑向間隙。間隙控制迴路使用比例-積分-微分控制器，微分控制器可以有效增加轉軸運動系統之阻尼，使轉軸運動更易於穩定。
本文之控制器使用Texas Instrument 公司所生產數位訊號處理器(TMS320F28075)，並透過C 語言撰寫馬達驅動繞組的電磁轉矩控制策略及磁軸承繞組的間隙控制策略。驅動電路使用兩組三相三臂式換流器，加上閘極驅動電路及周邊回授電路，完成磁軸承控制系統的實體製作。文中採用Matlab/Simulink 模擬軟體分析電磁轉矩控制策略及間隙控制策略之可行性，並依此作為實驗時的重要參考。實測結果方面，電磁轉矩控制策略輸出轉矩為0.6N-m。徑向的間隙控制實測，軸承外加干擾力最大為49N，在200rpm 時，X、Y 軸最大間隙穩誤差值在+40μm~-220μm ，符合磁軸承馬達實際應用之需求。

The purpose of this paper is to develop a control system for a contactless magnetic bearing motor. The magnetic bearing motor uses magnetic force to control the rotating shaft in the center of the air gap,which effectively reduces the frictional losses caused by the motor operation. The structure of this magnetic bearing motor is 12 slots and 8 poles double winding structure, which are motor drive winding and magnetic bearing winding respectively. The motor drive winding is
matched with a torque control strategy to control the output torque of the magnetic bearing motor. The magnetic bearing winding is matched with a gap control strategy to control the position of the magnetic bearing motor shaft in the air gap, so that the shaft rotates at the origin. The gap control uses the eddy current gap sensing device PU-14 to detect the X-axis and Y-axis radial gaps. The gap control loop uses a proportional-integral-derivative controller. The derivative controller can effectively increase the damping of the shaft motion system and make the shaft motion more stable.

The control system in this paper uses a digital signal processor (TMS320F28075) produced by Texas Instrument, and the torque control strategy of the motor drive winding and the gap control strategy of the magnetic bearing winding use C language. The drive circuit uses two groups of three-phase three-arm inverters, plus a gate drive circuit and peripheral feedback circuits to complete the manufacture of the magnetic bearing control system. In this paper, Matlab/Simulink simulation software is used to analyze the feasibility of torque control strategy and gap control strategy, which is regarded as an important reference in the experiment. In terms of actual measurement results, the torque command of the torque control is 0.6 Nm. Measurement of radial gap control, when the test condition is that the maximum external interference force of the bearing is 49 N and the rotor speed is 200rpm, the steady-state error of the maximum
gap between the X and Y axis is between +40μm~-220μm. It meets the requirements of actual application of magnetic bearing motor.

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