Metal wire drawing is a critical stage in wire production. The straight-line wire drawing machine consists of multiple drawing heads, cold-drawing the wire to the target specification in a single pass through progressive drawing. It features high efficiency and strong continuity, making it widely used in high-precision wire processing fields.

During high-speed continuous production, the VFD must simultaneously meet several stringent requirements: outputting high torque with stable operation during startup and low-frequency stages; controllable swing amplitude of the tension swing arm during wire threading; fast and stable response to target tension; and possessing system functions such as arbitrary die skipping, meter-stop, weight-stop, and die wear estimation to ensure the coordinated operation of the entire line.

The system uses a PLC as the control core to perform all logic operations and data processing, achieving efficient communication with the VFD. The main VFD quickly responds to PLC commands to ensure stable and uniform wire drawing tension; the take-up VFD cooperates with a constant tension control algorithm to evenly wind the finished wire onto the spool or 'elephant nose' take-up device, realizing fully automated closed-loop control throughout the process.

• Leading Constant Tension Control Algorithm