High-speed positioning of warp knitting machine shogging system based on feedforward control

In response to the difficulty of meeting the requirements of high speed,high response and accurate positioning of the electronic shogging system usually controlled by the conventional PID on warp-knitting machine,a three-closed-loop PID control system consisting of conventional position loop,speed loop and current loop was designed based on the analysis of physical model of servo motor.Introduction of the feedforward control of current loop and speed loop into the system improves the high-speed positioning control performance of the guide bar.MatLab simulation and practical operation on RSE4-1 high-speed warp knitting machine show that the signal tracking performance of the control system can be improved effectively by using the feedward PID control.Compared with the electronic shogging system controlled by the conventional PID control,its positioning time is shortened by 2 ms,with faster response and more accurate positioning.