模糊控制應用於線切割放電加工厚度變化工件之研究

A Study on Fuzzy WEDM Process with Workpieces of Variant Height

林奕圻(Yi-Chi Lin)

指導教授 ： 廖運炫

國立臺灣大學/工學院/機械工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.02886

摘要

本文目的在於改善線切割放電加工機在切割工件厚度變化處之不穩定現象。文中先以實驗求得不同厚度與伺服電壓下之進給速率，設此進給速率為理想進給速率。再設計一模糊控制器，以間隙電壓、間隙電壓變化量與目前進給速率和理想進給速率之差距為控制器之輸入變數制定模糊控制法則，對厚度變化之瞬間制定控制策略，在加工時由控制器推論出適合之進給速率。
由實驗結果顯示，本文所設計之控制系統，可在經過工件段差時，推論出最適當的進給速率，大幅度穩定加工狀態與提升暫態性能。且進給速率在控制下皆未產生超越量(overshoot)或震盪，避免了因進給速率過度加速所造成之危機。加工過程中，進給速率在穩態時最大變動量約0.05mm/min。

關鍵字

線切割放電加工 ； 模糊控制 ； 間隙電壓

並列摘要

The purpose of this study is to overcome the instability occurring in the Wire-EDM process when the cutting wire is encountering the abrupt change of the height of the workpieces. An algorithm which is able to estimate the optimal feed rate automatically during the Wire-EDM process is proposed. A fuzzy controller with multiple control rules for different changing conditions of the height of the workpieces is designed. The most appropriate feed rate is calculated by the fuzzy controller according to the present gap voltage and the estimated workpiece height. Experiments have shown that sat factory performance is obtained with the assistance of the fuzzy controller. The Wire-EDM process becomes stably without overshoot and oscillation even when the height of the workpiece changes abruptly. The transient performance is also enhanced, and the maximum variation of feed rate in the steady state during the Wire-EDM process is 0.05mm/min.

並列關鍵字

Wire-EDM machines ； Fuzzy ； Gap voltage

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