In recent years, with the continuous advancement of mechanical and electrical integration in textile machinery, AC frequency conversion speed control has become a prevailing trend. In most newly developed textile equipment, the use of AC asynchronous motor frequency converters is now almost universal. This technology not only improves efficiency but also enhances precision and reduces energy consumption.
1. Characteristics of AC Frequency Conversion Speed Regulation
1.1 Energy Saving and Cost Reduction
Textile mills rely heavily on air conditioning systems. When air conditioner motors are controlled via frequency converters, power consumption significantly decreases, leading to substantial cost savings. According to data from a company, 12 air conditioners can save over 240,000 yuan annually, with an average reduction in energy consumption of 6–7 percentage points.
1.2 Simplified Mechanism and Enhanced Performance
By using PLCs or industrial computers, multiple motors can be synchronized and coordinated through frequency converters. This allows precise control of machine movements based on production process curves, simplifying mechanical structures. For example, in roving frames, AC frequency conversion eliminates the need for cone wheel shifting mechanisms, solving issues like belt slippage and inaccurate shifting.
Similarly, in spinning frames, the use of frequency converters removes forming cams, preventing pauses at the peach bottom and impacts at the peach top, resulting in better yarn quality and smoother high-speed unwinding. Variable speed controls are also used to adjust the main motor’s rotation speed, ensuring smooth transitions between large, medium, and small yarns, which helps reduce breakage rates.
2. Application of AC Frequency Conversion Technology
There are two main types of AC motors controlled by inverters in textile machinery: the Y series AC asynchronous motor, commonly used in machines requiring less precise speed control, and specialized AC variable frequency motors designed for high accuracy and wide speed ranges.
Different inverter types include:
(1) V/F open-loop control: Simple and reliable, but limited to a 10:1 speed range and 2–5% accuracy. Suitable for less demanding applications like knitting machines.
(2) Sensorless vector control: Offers better low-speed performance, higher reliability, and improved torque characteristics. With 0.5–1% accuracy and a 20:1 speed range, it's ideal for printing and dyeing machines.
(3) Closed-loop vector control with feedback: Known as AC servo motors, this system offers up to 100:1 speed range and high precision. It uses IGBTs instead of GTRs for faster switching, making it suitable for high-speed machines like warping, sizing, and chemical fiber spinning equipment.
Some advanced machines, such as Barmag winders and DLENES hot rollers, integrate inverters directly with control panels and mechanical components, reducing size and increasing reliability.
3. Real-World Applications of Frequency Converters in Textiles
Frequency converters are widely used across all stages of textile production, including carding, combing, drawing, roving, spinning, and weaving. They are also found in knitting, non-woven, and chemical fiber machinery, as well as in printing and dyeing equipment. Two notable examples are the FA491 high-speed roving frame and the GA308 sizing machine.
3.1 FA491 High-Speed Roving Frame
This modern roving machine uses four industrial motors, a PLC, and inverters to control the flyer, roller, tube, and dragon ribs. It eliminates the cone wheel and molding mechanisms, improving efficiency, reliability, and ease of operation. With a maximum speed of 1,500 rpm, it features man-machine dialogue and automatic parking positioning, making it a high-level roving machine.
3.2 GA308 Sizing Machine
The GA308 uses distributed AC drive systems, with the sizing tank, drying cylinder, and weaving shaft driven by AC variable frequency motors. The tow roller is controlled by an AC servo motor. It includes five inverters, two servo controllers, and various sensors, all managed by an industrial computer and PLC. This system ensures high precision, stable performance, and reduced failure rates, making it a top-tier sizing machine.
4. Future Prospects for Frequency Converters in Textiles
As China's textile industry becomes more globalized, there remains a gap compared to international standards. To close this gap, continued improvements in the mechatronics of textile machinery are essential. Applying AC frequency conversion technology more effectively will play a key role in achieving higher efficiency, precision, and competitiveness in the global market.
Other Medals,Marathon Run Medal,Blank Marathon Medal,Zinc Alloy Blank Medal
Topwell Crafts Co., Ltd , https://www.topwellmetal.com