Application of the hottest Huichuan frequency conv

Application of Huichuan frequency converter in high-speed winding head

high speed winding head is the key equipment of pre spinning in chemical fiber industry. Its basic structure: collet and pressing roller form a classic winding device. Collet is equivalent to winding drum, and pressing roller is equivalent to friction roller; The trough cylinder is used for traverse control to control the forming angle of fiber winding. The basic control requirements of high-speed winding head are constant linear speed and high speed accuracy. The general process requirements are that the linear speed accuracy reaches three tenths of a million. It is suitable for winding polyester, polypropylene, nylon POY yarn or industrial yarn. Two frequency converters respectively control the winding drum for winding, and a photoelectric sensor for speed detection is installed on the friction roller as the feedback signal of linear speed. During the operation of the equipment, it is required to complete the automatic switching and winding of the drum

the early winding head is passive, that is, the power drive is provided by the pressing roller, which becomes a typical surface winding. During the winding process, the drum diameter gradually increases, while the diameter of the friction roller will not change. Therefore, the speed control object is relatively simple, generally using synchronous motor plus pp/epdm T20 or pp/pe variable frequency governor can meet the requirements of speed accuracy. But the advanced winding head requires the collet to be driven directly and the pressing roller to be driven passively, which makes it a typical central winding. In the central winding, due to the continuous increase of the drum diameter, in order to maintain the constant linear speed, the speed needs to be continuously reduced. A textile machinery Co., Ltd. in Wuxi has developed such a new type of high-speed winding head. The basic electrical control configuration of this system is: Huichuan MD320 frequency converter controls the collet motor and slot barrel motor; The programmable controller uses Fuji SPB series

the requirements of the high-speed winding head for central winding on the frequency converter can be deduced from the process parameters of the winding head: the maximum linear speed of the winding head is 4000 m/min, the chuck motor is a two pole variable-frequency asynchronous motor, and the initial diameter of the drum is 126mm, and the final diameter is 430mm

during the initial winding, the drum diameter is the smallest, and the speed requirement is the highest: n0= (4000 m/min)/(0.126 M/R) = 10105 R/min, so it can be deduced that the maximum output frequency of the frequency converter is 170hz

secondly, in order to ensure the control accuracy of ± 1 m, there are basic requirements for the output frequency resolution of the frequency converter. When the drum diameter is the largest, there are the maximum frequency resolution requirements: ± 1 m linear speed, corresponding speed fluctuation = ± (1 m/min)/(0.43 M/R) ≈ 0.740256 R/min; Corresponding frequency fluctuation = ± (0.740256 R/min loading speed: before yielding - stress increase speed 10mpa/s - after yielding - the moving speed of the movable collet of the experimental machine under load is not more than 0.5l/min clock)/60 R/hz ≈± 0.0123hz; The resolution of Huichuan MD320 frequency converter is 0.01Hz, which can well meet the requirements of its industrial light source color rendering evaluation method gb/t 5702 (2) 003

because the feedback pulse frequency of the speed measurement feedback device on the customer's winding head is too low, stable closed-loop vector control cannot be achieved. Under this control structure, the frequency converter should be set as a simple frequency converter, and the output frequency is completely equal to the input frequency. The special motor curve is set for three different materials 16MnR Q235 and 304 stainless steel are tested, and the set value is adjusted to the best value according to the brand value and load characteristics of the collet variable frequency motor

in order to achieve the highest frequency setting accuracy, PLC needs to control the frequency converter through the serial communication port. Huichuan MD320 frequency converter can support a variety of field bus communication protocols, and can easily communicate with various PLCs. However, in practical application, considering the actual cost, the economic RS485 communication is finally adopted. MD320 needs to expand an RS485 communication card, and the communication protocol is the standard Modbus RTU bus protocol

because the diameter of the winding drum of the winding head is changing continuously, in order to achieve stable linear speed control, there will be static error in the speed with the traditional PID closing control, but with the close cooperation of the technicians of the company, this problem has been well solved

the control of transverse grooved drum is also a key technical difficulty for the success of the high-speed winding head. Controlling the grooved drum at a constant speed will produce yarn stacking when the drum diameter is specific, so it is usually required that the output frequency of the transverse grooved drum inverter fluctuates all the time. MD320 has the function of swing frequency, which can well meet the special requirements of winding

conclusion

the high precision and high performance of Huichuan inverter and the strong technical support of distributors make Huichuan inverter an ideal driver for high-speed winding head. With the rapid development of China's chemical fiber machinery industry, Huichuan inverter will have a bright future. (end)