1 Introduction
With the development of paper processing technology and the upgrading of coating processing equipment, detecting and controlling the paper tension between various production equipment during the coating production process is an important technical measure to improve product quality and output.
A coating machine is a device that applies a layer of selected coating (adhesive, ink, etc.) to raw materials (paper, fabric, plastic, etc.), dries them, and then rewinds them. The entire process consists of several stages: unwinding, multi-stage synchronous control, and rewinding. It requires constant paper tension, i.e., constant linear speed, throughout the operation.
Technical requirements for coating machines
1. The tension of the raw material must be kept constant during both unwinding and rewinding.
2. Regardless of changes in roll diameter, a steady and consistent linear speed must be maintained during unwinding and rewinding.
3. The unwinding control, intermediate multi-stage synchronous control, and rewinding control speeds must be synchronized to avoid being too loose or too tight, or even breaking the raw material.
2. Introduction to the HD50 High-Performance Vector Control Driver
The HD50 series features a modular and customizable design, offering excellent open-loop and closed-loop vector control performance, enabling control of three-phase AC asynchronous motors and three-phase AC synchronous motors.
The HD50 series features built-in expansion function interfaces and multiple encoder interfaces, enabling speed control, torque control, constant tension control, and servo positioning control. It meets the complex and high-precision transmission requirements of various fields such as hoisting machinery, printing machinery, and high-end machine tools, providing a complete solution for equipment manufacturing customers.
Features of the 3 HD50 High-Performance Vector Control Driver
HD50 High-Performance Vector Control Driver
1. Unique tension control function, multiple tension control options, built-in automatic roll diameter calculation module, advanced inertia calculation module, flexible tension taper adjustment, and automatic material breakage detection function.
2. Multiple torque setting methods, torque control and speed control can be flexibly adjusted.
3. Higher performance VC control method, speed control accuracy: ±0.05%, speed control range: 1:1000, torque control response: < 50ms
Starting torque: 180% of rated torque/0Hz.
4. Excellent current and voltage control algorithms and advanced overcurrent suppression enable operation without overcurrent or tripping under arbitrary acceleration/deceleration times and impact load conditions.
5. It can drive synchronous and asynchronous motors, and the drive switching between synchronous and asynchronous motors can be realized through parameter settings.
6. It has basic servo functions, servo positioning mode, and spindle orientation mode.
7. The products have higher voltage ratings, including products with 500-690V voltage output.
8. Offers a wide range of encoder cards to adapt to various encoders, with frequency division output.
4. Application of HD50 high-performance vector control driver in coating machine
Option 1 Torque Control Mode: The required force varies with the roll diameter, and the inertia calculation module automatically adjusts to maintain a constant linear velocity.
Option 2 Roll Diameter Calculation Mode: Based on parameters such as roll diameter and material thickness, the built-in automatic roll diameter calculation module adjusts to maintain a constant linear speed.
Option 3 PID Feedback Mode: Adjust the speed difference through pulse PID feedback to maintain a constant linear velocity.
This case study adopts Solution 3, and the application site is a factory in Guangming New District, Shenzhen. The commissioning process and results of the winding frequency converter are as follows:
4.1 Debugging Process
(1) Wiring according to Figure 1;
(2) Set the motor parameters according to the motor nameplate;
(3) Disconnect the motor load, use the jog function to determine the motor rotation direction, and change the wiring to the forward rotation direction;
(4) Perform motor parameter self-tuning;
(5) Set the maximum output frequency and upper limit frequency;
(6) Set the command to specify the channel and frequency for the channel;
(7) Set acceleration and deceleration time;
(8) Set terminal functions;
4.2 Control signal wiring
The control signal wiring is shown in Figure 1, where AI1 is the frequency setpoint, DI1 is forward rotation, DI3 is reverse rotation, and DI6 is the pulse PID feedback input.
4.3 Final Parameter Settings
4.4 Actual Results
According to on-site tests, when the winding length reaches approximately 600m, the roll diameter change is small, the PID pulse feedback is minimal, resulting in smooth winding and uniform coating. Between 600m and 1200m, the roll diameter changes significantly. Through PID pulse feedback, the rotation speed is adjusted promptly to maintain a constant linear speed, achieving excellent coating results. Work efficiency has been improved by over 20% compared to traditional methods. The operation method has reduced reliance on operator skills and significantly improved automation, earning high praise from users.
4.5 Debugging Precautions
1. Accurate motor parameters are required, therefore the motor nameplate values must be correctly entered, and motor parameter self-tuning must be performed.
2. If a large starting torque is required at low frequencies, simply set F09.07 to 0 (automatic torque boost) to meet the requirements.
5. Conclusion
The HD50 high-performance vector control drive has been successfully applied in the packaging machinery field. Its superior performance (high low-frequency torque, wide speed range, high steady-state accuracy, flexible and convenient operation, and comprehensive protection functions), diverse control schemes, and high reliability have been fully verified, and it fully meets the process control requirements of coating machines.
