標題: Extended Reaching Phase for Discrete-Time Sliding Mode Control of Sampled-Data Systems with Control Magnitude Constraints有限輸入取樣資料系統之延長迫近模態離散型順滑控制設計 作者: 蘇武昌 關鍵字: 順滑模態sliding mode電子電機工程類迫近模態等效控制取樣資料系統有限輸入基礎研究reaching modeequivalent controlsampled-data systemscontrol constraints 摘要: Utkin』s discrete time equivalent control is a 「one-step reaching」 control design strategy. It enables a system to enter an sliding layer within one sampling period, T. However, for a sampled-data system with control magnitude constraints, such a one-step reaching control will not be admissible for implementation if the current state is not close enough to the sliding surface. Physically, such an instantaneous reaching motion requires a control magnitude that is a reciprocal function of T. It certainly will go beyond the control constraints unless T is large enough. )(TO 2An idea of extended reaching phase is proposed to prolong the course from the current state to the sliding surface so as to reduce the required control efforts that satisfy the control constraints. The extension is made by introducing an integer parameter h such that the intended reaching time is hT instead of T. The parameter h diminishes as the state approaches the sliding surface and finally enters an O(T) boundary layer of the sliding surface, in which h becomes one. In this manner, the control magnitude will keep admissible and the state attains a 「soft landing」 to the sliding surface. The combination of the reaching control (h>1) and the sliding control (h=1) will be seen to be smooth on the way to and also in discrete-time sliding mode.以Utkin的離散型等效控制為基礎的控制設計策略，可使系統以「一步到位」的方式直接進入順滑層中，其中T為取樣週期。然而在有限輸入的取樣資料系統中，如此快速的迫近模態明顯造成控制量超過可容許範圍，以致產生無法實現的問題。就物理上的直觀來看，欲將原本遠離滑動曲面的狀態在一個取樣週期的時間之內帶進順滑模態，所需的控制量將與T成反比，除非目前狀態已經足夠接近滑動曲面，否則所需的控制數值必然遠大於可容許輸入的上限。因此，「一步到位」的控制策略在有限輸入取樣資料系統中必須加以修正。 )(2TO本計畫提出延長迫近模態的觀念，在控制法則的設計中引進一個調整參數來延長系統迫近順滑曲面的步數，藉以降低控制量以符合其輸入容許範圍，並確保系統狀態朝滑動曲面逼近。延長步數的調整與狀態和滑動曲面之間的距離有關，本研究定義一個順滑曲面的O(T)邊界層，待系統漸漸進入此邊界層時，延長步數將隨而調整，最後自然縮小為1，使系統順利進入順滑層，得以「軟著陸」的方式進入順滑模態，有助於控制法則在整個迫近與順滑模態過程中的平滑度。 URI: http://hdl.handle.net/11455/48904 其他識別: NSC96-2221-E005-042 文章連結: http://grbsearch.stpi.narl.org.tw/GRB/result.jsp?id=1464425&plan_no=NSC96-2221-E005-042&plan_year=96&projkey=PB9609-4757&target=plan&highStr=*&check=0&pnchDesc=%E6%9C%89%E9%99%90%E8%BC%B8%E5%85%A5%E5%8F%96%E6%A8%A3%E8%B3%87%E6%96%99%E7%B3%BB%E7%B5%B1%E4%B9%8B%E5%BB%B6%E9%95%B7%E8%BF%AB%E8%BF%91%E6%A8%A1%E6%85%8B%E9%9B%A2%E6%95%A3%E5%9E%8B%E9%A0%86%E6%BB%91%E6%8E%A7%E5%88%B6%E8%A8%AD%E8%A8%88 顯示於類別： 電機工程學系所

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