以VLSI做放電控制器之研製

Abstract

放電加工本質上就是一種效率不高的加工方式，但是放電加工能對特殊超 硬合金鋼材作加工，藉由電極的製作方式可以實施特殊形狀工件的加工。 因此，如何保持同樣的加工優點，加快放電加工的效率，便是我們希望研 究的課題。在本論文我們提出以單晶片微處理器配合可程式邏輯閘陣列為 基礎的全數位化架構的放電控制器，其特點在於：（1）藉由單一的可程 式邏輯閘陣列作為放電波形的產生及偵測統計工作，對於在研發過程中， 產生的構想可隨時實現，而不需要更改其他硬體電路。（2）配合網路架 構，可經由網路傳回放電狀態及結果，驅動伺服機構作間隙調整。（3） 在控制方法上採用模糊控制理論，配合專家知識及操作經驗，來獲取控制 法則，以解決缺乏標準數學模型的放電加工現象的控制問題。本論文的研 究工作，除了放電控制器、CNC放電加工所需的行星加工機能及排渣動作 的研製外，並整合交流式伺服控制系統，製作出初具規模的 CNC放電加工 機。對於複雜的放電加工現象，提高加工效率而言，本論文只能算完成初 步的工作，但所建立的完整實驗環境及改進的構想，卻已為將來更深入的 研究工作，扎下深厚的基礎。 EDM is virtually a machining way of low efficiency. Yet, EDM can process the special super hard alloy and the product of special shape by making the same electrode. We have concentrating on the subject of how to promote the efficiency of EDM without degrading the virtue of the product. In this thesis, we propose a single-chip microprocessor and PGA based system architecture. The key features of this system include : (1) By using a single VLSI element-PGA to produce electrical pulses, to detect and analyse the feedback signal. In research duration, it is not necessary to change other hardware while having new ideals to improve. (2) By using the network architecture to access the discharging status and control we can set the command at personal computer and drive the servo mechanisms. (3) Since system model is complicated and get system parameters is not available, we using fuzzy control theory to develop the control methods by cooperating with expert knowledge and experience. In the thesis, we studied the manufacturing of EDM controller as well as the planetary maching and pumping motions, composite the AC servo controlling system, and then, came up with the prototype CNC EDM as a result. We have completed the first study in the complicate phenomena of EDM and the method to promote the efficiency. Besides, The construction of the whole experimental enviroment and the improving ideals have been planted into the works and will be very helpful in the furture research.