SHENZHEN INVT ELECTRIC CO.,LTD. Tension Control SHENZHEN INVT ELECTRIC CO.,LTD. www.invt.com.cn

Paper making, paper processing; Application Field Paper making, paper processing; Printing and dyeing; Packaging; Cables, optical cables; Adhesive tape manufacture; Textile, leather; Wire-drawing machine; Metal foil material processing and so on.

Schematic Diagram www.invt.com.cn

Installation of Tension Card

Winding Diameter Calculation Linear speed method D =(i × N × V)/(π × f) Where, i: mechanical drive ratio; N: pole pairs of motor; V: linear speed; f: current match frequency. 2. Thickness accumulation method Strip thickness accumulation D = D0+2×n×d(Winding) (Unwinding: D = D0-2×n×d ) Where, D0: initial winding diameter; n: number of winding/unwinding turns; d: average thickness of strip material.

Winding Diameter Calculation Wire thickness accumulation D = D0+2×d×(n/N) Where, D0: initial winding diameter; d: average thickness of wire; n: number of winding/unwinding turns; N: number of turns every layer. 3. Analog or high-speed pulse detection Ultrasonic sensor or CCD sensor.

Tension Taper Coefficient Only valid for winding. Make tight inside but loose outside of winding roller to protect the coiled material. F = F0×[1-K×(1-D0/D)] Where, F: Actual output tension; F0: Set tension; K: Taper coefficient; D0: Initial value of winding diameter; D: Current winding diameter value.

Traditional Tension Control System Tension Sensor Tension Sensor Unwinding Winding Main Drive Tension Controller Tension Controller Magnetism Brake Inverter Inverter Magnetism Clutch PLC Given Speed

Disadvantages Not long using life. The magnetism powder will decrease with the using of machine; Too high maintenance cost (the magnetism is expensive; Low speed; Low efficiency.

Tension Control Mode Tension open loop torque control (PG card and Coder for detecting the speed are necessary) Maintain the tension constant by controlling the motor output torque. T = (F×D) / (2×i) Where: T Output torque command of inverter; F Tension setting command; D Rotating diameter of the reel winding; I Mechanical drive ratio.

Tension open loop torque control Main Drive Unwinding Winding Coder Coder Motor Motor CHV Inverter CHV tension Inverter CHV tension Inverter

Tension Control Mode Tension feedback torque control (PG card, encoder for detecting the speed and tension feedback are necessary) Tension Sensor Tension Sensor Unwinding Main Drive Winding Coder Coder Motor Motor CHV Inverter CHV tension Inverter CHV tension Inverter

Tension Control Mode 3. Tension feedback speed control Maintain the tension constant by adjusting the motor rotational speed. Synchronous match frequency command: f = (V×N×i)/((π×D) Where, f Current match frequency of inverter; V Linear speed of material; N Pole pairs of motor; I Mechanical drive ratio; D Winding diameter of reel

Tension feedback speed control Tension Sensor Tension Sensor Main Drive Winding Unwinding CHV tension Inverter CHV tension Inverter CHV Inverter

Schematic Diagram of Five-step Wire Drawing Control

Advantages Simple structure and clear logic; More stable control; Lower cost and convenient maintenance; Improve the inertia compensation; Excellent solutions of wire drawing process and energy saving; Meet the technologic requirement in synchronization and constant tension winding control.

Prepared by : Ms.Demi Dong Checked by : Mr. Jian Wang Tel: 86-755-86028447 Fax: 86-755-86028420 Mobile phone: +86 135 109 260 31 Online MSN Messenger support:  demiping@hotmail.com Online Skype Support:  demiping@skype.com E-mail:   dongping@invt.com.cn                     dongpingdemi@gmail.com

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