Abstract
Chaos occurs in the flexible shaft rotating-lifting (FSRL) system of crystal growth process. Chaotic swing does harm to the quality of mono-silicon crystal production. Therefore, it must be suppressed. Previous studies have proposed impulse control method to suppress the chaos in crystal growth process. However, the impulses require sudden and intermittent changes to the rotation speed, which are difficult to implement through the soft rope connection. In this work, a small amplitude resonant perturbation to the rotation speed is being proposed to suppress chaos in the FSRL system. The system state, given by the swing angle between the rotation center on the vertical axis and the soft shaft, is observed by measuring the force on the soft shaft and by using the untraced Kalman filter. The control parameters are selected by calculating the Lyapunov exponent. As compared with the previous impulse control methods, the proposed small amplitude resonant perturbation method engenders a small continuous change instead of the sudden change in the rotation speed. In addition, the proposed method does not alter the average rotation speed, which complies with the crystal growth technique requirement. The effectiveness of the proposed chaos control method is validated by numerical simulations.
Original language | English |
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Pages (from-to) | 2655-2669 |
Number of pages | 15 |
Journal | Nonlinear Dynamics |
Volume | 108 |
Issue number | 3 |
Early online date | 11 Mar 2022 |
DOIs | |
Publication status | Published - 1 May 2022 |
Bibliographical note
FundingThis work was supported in part by the Shaanxi Provincial Special Support Program for Science and Technology Innovation Leader.
Keywords
- Chaos supression
- Crystal growth technique
- Flexible shaft rotating
- lifting system
- Resonant perturbation
- LYAPUNOV EXPONENT