| As a new type high-tech material, fiber composite material can remedy many disadvantages of metal material and has now been applied more and more widely. Winding molding is a commonly-used molding method for composite fiber materials, in which the fiber winding tension is an important parameter, since the winding tension directly influences the quality of winded products, making winding tension control a key technique in fiber winding. In this process, suitable and stable tension helps to increase the winded components'abilities again internal pressure and fatigue.Two types of tension control system are researched and manufactured by this project. The open-loop tension control system, with PLC as the main controller, the industrial control computer as the upper-host, alternating numeric servo-electromotor as the actuator, is equipped with two compensation techniques for the compensation of (1) the tension variation caused by radius change with radius following equipment and (2) the tension change caused by yarn-pulling speed change with acceleration. Besides, the closed-loop tension control system, with PLC as the main controller, the industrial control computer as the upper-host, alternating numeric servo-electromotor and air cylinder as the actuators, equipped with the angle sensor of real time feedback filament tension change is designed. Alternating numeric servo-electromotor works as executing element and taking back motor, which predigests the system.Two kinds of tension control schemes are designed, and detailed analysis is made on their principles, static and dynamic properties of the actuator and the selected parameters of its main components. The two kinds of tension control schemes are discussed with control theory, on the basis of study on unwinding scroll and swing bar respectively, and the mathematical models of the two schemes is established. The integral separated PID control algorithm suitable for the closed-loop system is suggested.The paper presents the development of PLC ladder control program, upper-host control program and intercommunion control program, according to the modularization requirements and control functions. On the basis of the control scheme, the functions of the main function modules are analyzed, and then the two key techniques of serial communication and PID arithmetic are analyzed.Because the tension control system is a non-linear system with the characteristics of multi-inputs, coupling and time variation, a satisfactory control effect can hardly be attained from tension system designed with conventional control theory. As the Fuzzy control has the characteristics of independence on the precise mathematical model of the controlled object, high adaptability and good robustness, the theory of the Fuzzy control is applied on the system. Fuzzy-PID controller is presented for the closed-loop system, which overcomes the shortcoming of traditional fuzzy controller such as quantized error, dead zone, and bad steady state characteristics. Effective fuzzy control algorithm is derived, using the theory of adapt fuzzy control in big error range and adapt PID control in small error range. Fuzzy-PID controller combines the advantages of PID and fuzzy control, and has good dynamic property of fuzzy controllers, eliminates the steady error and amends the bad adaptability of PID controller. Therefore Fuzzy-PID controller can highly improve the static and dynamic properties of the system.The control system is debugged in part and as a whole to ensure the correctness and stability of long time runs. Tension control in the fiber winding process is validated, combined with NC winding machine. Experimental results proved that the principle of the design schemes on the basis of fuzzy control is right with small tension deviation, short response time and thus well meets the requirements of the the system.
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