The Loom Tension Controller Design-Modeling And Simulation

During the process of weaving, the warp beam radius decreases from full shaft to ahollow shaft. If the output torque of brushless DC servo motor is always the same, thechange of warp tension caused by warp beam radius will be very large. It will affect thequality of the fabric, such as the uneven density and bad lines.Therefore, in order to improve the quality of the fabric, we must control the tensionof the warp. Let-off and take-up process is very important when gripper looms work. Thepaper mainly introduces the modeling and simulation of the inherent system of gripperloom warp tension control system. The inherent system of gripper loom warp tensioncontrol system consists of warp drive motor, reducer gearbox, swinging beam, beam, warptension sensor and so on.In this paper, we establish mathematical models of all aspects of the inherent system,then establish the dynamic mathematical model of inherent system. Using MATLABsoftware platform, we write m file program and draw pen-loop bode diagram and unit stepresponse curve of the inherent system. After running the program, the phase margin ofinherent system indicates that the inherent system is stable.By analyzing the open-loop bode diagram and its unit step response curve of inherentsystem, we find that the system is stable, but the overshoot is large, the steady-stateaccuracy is not high, the stability is not good, and the ability of anti-high-frequency noiseis not strong. In order to weave good cloth, the inherent system must be corrected. Thisarticle selects ahead of correction to correct the natural system.By repeatedly trying, we obtain the optimal parameters of phase-lead network. Afterthe correction, phase angle stability margin and the overshoot of the inherent system isimproved to meet the need of the system. Do discrete process of the transfer function ofthe inherent system, establish the pulse transfer function and the differential equations ofthe inherent system, analyze and calculate the discrete stability, and then make digitalcorrection. We design a digital correction. The discrete systems is no difference system atleast beat in unit step signal. The warp tension is well controlled after correction. It avoidsthe uneven density of woven fabric caused by uneven warp tension and improve thequality of textile fabric.