磁浮軸承基於牛頓法之迭代前饋不平衡干擾補償

Feedforward, Iterative Unbalance Compensation of Magnetic Bearing System Using Newton's Method

張藏謙(Zang-Cian Jhang)

指導教授 ： 葉廷仁

國立清華大學/工學院/動力機械工程學系/碩士(2019年)

摘要

一般而言，在旋轉機械中轉子會因質量分布不均而有質心偏移的情形發生，這導致轉子運轉時會受到不平衡干擾而產生震動。在控制方面來說，閉迴路控制器能提供系統穩定性及足夠的剛性，而補償的方式最好能在不影系統穩定性的前提下抑制不平衡干擾。故本研究將建立磁浮軸承不平衡干擾補償的前饋控制演算法，並透過模擬及實驗進行驗證。在前饋控制中，將以同步弦波偵測位移訊號的振幅及相對相位，結合反轉移函數矩陣計算前饋補償量及補償相位，並以同步脈衝訊號做為時間基準點進行補償。考慮系統鑑別計算以及訊號感測誤差會使得補償效果受限，因此論文中提出以牛頓法迭代準確的補償量及補償相位，以增進效能。

關鍵字

同步弦波 ； 轉移函數矩陣 ； 牛頓法

並列摘要

In a rotating machine, the rotor’s center of gravity usually offsets from the rotational axis due to uneven mass distribution. Such an offset leads to periodical unbalance force and causes rotor to vibrate when it spins. In the magnetically levitated rotor system, while feedback control is used to provide stability and sufficient rigidity to possible disturbances, it is desired that a mechanism to cancel the unbalance force can be added externally without influencing the stability established by the feedback control. Therefore, this thesis devises a feedforward control algorithm for unbalanced compensation for magnetically levitated rotor systems. In the feedforward control algorithm, the amplitude and absolute phase of the displacement signal are firstly detected by using a synchronized sine wave generated from the pulse signal for the speed measurement. The information on amplitude and phase is then combined with the sensitivity transfer function matrix identified from the experiments to calculate the proper feedforward control needed to cancel the unbalance force. In order to account for the errors due to the sensor measurements as well as the inaccuracies in the sensitivity function identification, the thesis proposes to use the Newton method to iteratively compute the feedforward control efforts. The performance of the proposed unbalance compensation algorithm is verified by both simulations and experiments.

並列關鍵字

Synchronized Sine Wave ； Sensitivity Transfer Function Matrix ； Newton Method

參考文獻

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