Modeling and Control of WEDM Process of Silicon Single Crystal

doi:10.3901/JME.2018.17.149

Abstract

Abstract: EDM wire cutting semiconductor process, the gap between the workpiece and molybdenum wire is the key parameter to ensure the workpiece surface quality and cutting efficiency. The relationship between the gap between the silicon single crystal and the molybdenum wire is analyzed. Since the gap can not be measured in real time after the molybdenum wire has been cut into the workpiece, the instantaneous change of the gap can be estimated in real time according to the change of the current between the silicon single crystal and workpiece, and the feed rate of workpiece is used to ensure the gap. The system identification method is used to establish the control model of the current between the silicon single crystal and workpiece and the feed rate, and the order of the model is estimated by the F-test method, and the forgetting least squares is used to on-line estimate the model parameters. The controller of the minimum variance self-tuning controller is designed for real-time control of the cutting process. The experimental results show that the designed controller enhances the stability of the machining system and improves the processing surface quality under the premise of ensuring the processing efficiency.

Key words: minimum variance self-tuning control, modeling, silicon single crystal, WEDM

CLC Number:

TG661

LU Xiong, LI Shujuan, XIN Bin, WU Xiaoyu, ZHAO Ziyu, LI Yan, JIANG Bailing, LI Yuxi. Modeling and Control of WEDM Process of Silicon Single Crystal[J]. Journal of Mechanical Engineering, 2018, 54(17): 149-156.

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