應用模型參考適應控制之自動弧焊系統的開發

Development of an Automatic Arc Welding System Using a Model Reference Adaptive Control

盧鎮耀(Lu, Zhen-Yao) ； 陳威良(Chen, Wei-Liang) ； 盧光亞(Lu, Kuang-Ya)

《高雄應用科技大學工程科技學刊》 2卷2期 (2016/12) Pp. 1-12

https://doi.org/10.6553/JKTUET.2016.0202.01

摘要

本文研究的自動化屏蔽金屬弧焊（SMAW）機，主要是由二維的焊條進給機構所組成，故可將本系統，視為焊條進給控制系統。控制方法是根據傳統的手工焊接特性，用電流感測器線上量測電弧電流，再透過控制器調整焊條進給速度得到穩定的電弧電流，最後完成較佳的焊接成品。故本文建立的自動化SMAW 焊接機，可用來替代傳統的手工電孤焊接，使操作者可避免弧光、有毒氣體、燙傷、觸電……等災害。在控制器設計方面，本文運用函數估測器取代模型參考適應控制（MRAC）的系統參數估測。將估測範圍從系統參數估測直接擴大成函數估測和外界干擾訊號估測。改善傳統的MRAC 只能應用於線性系統的缺點，且增強了控制器的強健性。電腦模擬和焊接實驗的結果，印證本文提出的控制器在不經系統辨識步驟，可以有效的維持穩定的電弧電流，最後得到出色的焊接成品。

關鍵字

屏蔽金屬弧焊 ； 模型參考適應控制 ； 適應控制

並列摘要

In this paper, the automatic AC Shielded Metal Arc Welding (SMAW) machine consists essentially of two-dimensional electrode feed mechanism. Therefore, the system may be regarded as an electrode feed control system. The control method, based on conventional manual welding characteristics, utilizes current sensor to measure arc current on line, and then acquires stable arc current by adjusting electrode feed speed with controller to finish better welding product finally. Thus, the automatic SMAW welding machine may replace conventional manual arc welding, so that the operator may be kept from hazardous environment such as arc light, toxic gas, scalding, electrical shock, etc. For the controller design in this paper, the function estimator is used to replace the system parameter estimation of Model reference adaptive control (MRAC). The estimation range is expanded directly from system parameter estimation to function estimation and external disturbance signal estimation. The disadvantage of conventional MARC that could only apply to linear system is improved and the robustness of the controller is enhanced. The results of computer simulation and welding experiment verify that the controller proposed in this paper could maintain stable arc current effectively and result in good welding quality without system identification step.

並列關鍵字

shielded metal arc welding ； model reference adaptive control ； adaptive control