Tension Control of Winding Systems for PET Films by Fuzzy Sliding Mode Control
| Autor: | Peng, Chi-Chung, 彭棨俊 |
|---|---|
| Rok vydání: | 2005 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 93 In the winding process, the proper tension of material results in a higher quality product and more throughput to avoid material defects such as shape change, sags, wrinkles, rail, breakage, crushing the inner layers of material by the outer layers on the rewinder, etc.; besides, the proper linear transport velocity in the winding process also results in the tension which becomes more and more stable. In this paper, PET films are adopted for the material, and the winding system is constructed by a two-roller single-span mechanism for experimental platform. The main objective is to reduce the variations of the tension of films and linear transport velocity at desired values with designed controllers in the winding process. In tension controller design, we propose a fuzzy sliding mode controller (FSMC) by tuning the switching gain of the sliding mode control (SMC) law to attenuate the chattering phenomenon and obtain the accurate tension of films. The FSMC, which is based on theories of SMC and fuzzy logic control (FLC), unlike conventional SMC that has a fixed switching gain, has a varying switching gain which is adjusted properly by the FLC. The FLC of FSMC is a two-inputs and single-output structure, where the sliding function and the change of sliding function are chosen for two fuzzy input variables respectively, the switching gain of the sliding mode control law is chosen for the fuzzy output variable; furthermore, the fuzzy control rules are built on the characteristic of the response of the sliding function. For linear transport velocity control, the rewind motor is driven under the speed control mode. Due to the variation of the radius and the influence of the tension of films during the winding process, we design a PID controller to improve the robustness of linear transport velocity control, where gains of the PID controller are determined by trial and error. In the simulation and experiments, we compare FSMC with SMC at different desired tensions in the tension responses, and also compare the speed control mode of the rewind motor with PID controller at different desired linear transport velocities in the velocity responses. Finally, the simulation and experimental results indicate that FSMC is effective to attenuate the chattering phenomenon and reduce the variation of tension of films. Besides, the PID controller can alleviate the overshoot of the transient response of the linear transport velocity. Thus, the PID controller is effective to overcome the variation of the radius and the influence of the tension of films so that the accurate linear transport velocity can be achieved. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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