現今的工具機發展隨著航太工業、汽車工業及電子產業的蓬勃發展，其產業特色為產品精密度的品質要求甚高，而產品生命週期短暫，需要有快速開發新產品的能力，傳統工具機已經漸漸的不符合產業需求，因此未來工具機的發展需具備高速、高精度的加工特性，以符合高科技產業的潮流。線性馬達工具機有著高加速度，高精密的定位技術及無背隙等特點，別於一般的旋轉式馬達驅動器，線性馬達為直接驅動器，無須齒輪、滾珠導螺桿、聯軸器、齒條等傳動機構，由於沒有滾珠導螺桿所以不會產生背隙、撓曲等造成定位精度產生不良的問題，如此可大幅提升定位精度、速度及加速度。

傳統的工具機中垂直軸伺服馬達搭配的滾珠導螺桿，垂直軸向下運動時，導螺桿本身的摩擦力提供馬達部份向上的支持力，來抵抗重力對伺服軸的影響；但是線性馬達工具機的垂直軸並無此機構，易受重力加速度影響其定位精度。本論文主要探討線性馬達工具之垂直軸受重力加速度的影響與提出改善定位精度之方法，垂直軸機構以氣壓配重系統補償重力加速度，輔以控制策略，來解決垂直軸定位精度不良及響應過慢等問題，實現高速高精度伺服控制。

高性能伺服控制器的控制策略為於速度迴路中以干擾觀測器抑制外在干擾對於系統的影響，干擾觀測器中調整低通濾波器的參數，可增加系統對於外在干擾及雜訊的抑制能力。位置迴路中以PD控制器，降低系統的超越量，增加系統的暫態響應及穩定度，由於迴授控制器會有相位落後的問題，以零相位誤差追蹤控制器作為前饋控制器，預先補償輸入命令降低伺服落後現象。本論文以氣壓系統補償重力加速度和高性能伺服控制器實現高速高精度的線性馬達垂直軸定位控制。

　Today the technology of machine tools is highly developed, and the features of products are high precision, high quality and short lifecycle. Hence advanced machine tools must achieve goals of high speed and high precision. The characteristics of linear machine tools are high acceleration, accurate positioning, because they do not have ball screw, gear and transmission mechanism. Therefore linear machine tools do not have problems like backlash and deflection, but have better positioning and acceleration.

　In the case of vertical axes, traditional machine tools are usually composed of servo motors and ball screws. The screws can provide friction against gravity force while vertical axes move down. However, linear machine tools do no have ball screws to support themselves; they are easy to be influenced by gravity force. Hence, this thesis is going to propose a method about how to improve positioning precision on vertical axes in linear machine tools.

　The control strategy of high performance servo controllers adopts disturbance observer and a proportional controller to constrain disturbance and to obtain faster response in velocity loop. Disturbance observers can constrain disturbance and noise by tuning low-pass filters. Position loop controllers can improve transient response; however they have a problem of phase lag. Hence, this thesis utilizes a ZPETC to compensate this lag. In addition, this thesis also adopts an atmospheric pressure system to compensate gravity force and implements a high performance controller for linear motors on vertical axes.

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