In the winding control system of the dyeing machine, what are the tension control methods

Indirect tension control method:
Tension is indirectly controlled by controlling the torque of the winding motor. For example, according to the change of the winding diameter and the preset tension value, the required motor torque is calculated to maintain the stability of the tension. This method can meet the requirements of tension control to a certain extent, but it may have certain limitations for some occasions with extremely high tension accuracy requirements.
Direct tension control method:
Use a tension sensor to directly measure the tension and feed back the measured value to the control system. The control system adjusts the operating parameters of the motor according to the deviation of the tension to achieve precise tension control. For example, a high-precision tension sensor is used to monitor the tension in real time. Once the tension deviates from the set value, the control system quickly adjusts the speed or torque of the motor.
Composite tension control method:
Combines the advantages of indirect tension control and direct tension control to improve the performance and adaptability of tension control. For example, in the early stage of winding, when the winding diameter is small and the change is large, direct tension control is used to ensure tension accuracy; in the later stage of winding, when the winding diameter is large and the change is small, switch to indirect tension control to improve the stability of the system.
PID control method:
This is a classic control method. The tension deviation is adjusted through the combination of three links: proportion (P), integration (I) and differentiation (D). For example, according to the deviation size of the tension, the accumulation of the deviation and the rate of change of the deviation, the control amount is calculated to adjust the output of the motor so that the tension can be quickly stabilized near the set value.
Taking a high-end dyeing machine as an example, when processing thin and stretchable fabrics, a composite tension control method combined with PID control is used to ensure the tension accuracy in the initial stage and the stability of the tension during the entire winding process, effectively avoiding the problems of fabric stretching deformation and uneven dyeing.
In another practical application, for some special fabrics with low tolerance to tension fluctuations, the high standard requirement of tension control accuracy of ±1N is achieved by accurately debugging the sensors and control parameters in the direct tension control method.