Research On Tension Control System For Yarn Cladding Device

With the rapid economic development of our country’ and rising standard of people’s living, the requirement of textile products is increasingly improved. Since better elasticity and softness of covered yarn, it has been widely used in the senior fabric production. During the winding process, yarn tension influences not only the winding density of bobbin, but also the quality of forming bobbin. To reduce fluctuatiton of tension and improve quality of bobbin, we need to control the tension during the winding process. However, due to the parameters of tension control system exist the relationship of nonlinearity, time-varying, coupling and uncertainty, it is more difficult for traditonal PID control to achieve the requirements of high speed and high precision,. In order to improve the effect of tension control, the strengths of Sliding Mode Control, Backstepping Control and Extended State Observer are combined to design a control system, which is so called extended state observer based backstepping terminal sliding model control system. To prove the availability and superiority of the proposed algorithm, a hardware platform of the tension control system is built. This research project is supported by National Science and Technology Major Project(2015ZX04005006) and Science and Technology Planning Project of Guangdong Province(2012B011300056).Firstly, in order to obtain accurate model of the yarn tension control system, the method of mechanism is used to establish the mechanical models of the tension, rewind shaft and wind shaft and servo motor. On the basis of mechanical models, the whole system model of tension control is deduced from the coupling relationship between physcial quantities of each module. Since the tension control system has problems of nonlinearity, time-varying, coupling and uncertainty, many advanced algorithm such as Sliding Mode Control, Backstepping Control and Extended State Observer are used to design the tension controller. And the stability of designed control system is proved by using Lyapunov Stability Theory and Barbalat Lemma. Besides, it is not easy to optimize parameters by manual work, for the tuning parameters of designed controller are too many. Hence, Adaptive Genetic Algorithm is applied to optimize parameters. The simulation results show that intelligent algorithm can make the parameters rapidly converge to the optimal value, and the performance of controller is better after parameters optimization.Secondly, in order to evaluate the performance of anti-jamming for the designed tension controller, simulation is implemented in conditions of rectangular pulse or exponential attenuation interference. The simulation results show that even under two different types of interference, tension and speed still show the good tracking performance. Meanwhile, the average observation error for Extended State Observer is 0.0319 and 0.0168, respectively. These results also suggest that Extended State Observer can estimate different interference efficaciously, which improve the robustness of the control system.Lastly, a experimant platform for tension control is designed and built based on real-time control software of TwinCAT of Beckhoff company. The control system includes real-time module running on the software of TwinCAT and non real-time module developed by Microsoft Visual Studio 2010. The real-time module includes control module, servo drive module and tension measuring module. The non real-time module includes interaction interface of human-computer and data interaction between software and hardware of tension control platform. By comparing the experiment results of PID control and designed tension control strategy in this paper under different speeds, the control effects of proposed control strategy is better than PID control. And the errors of tension are less than ±1cN, which means that the proposed algorithm of backstepping terminal sliding model based on extended state observer and experimant platform for tension control can satisfy the requirement of tension control for yarn cladding device.