Research And Design Of New Intelligent Temperature Control System Of Heated Draw Roll

Heated draw roll, widely used in textile and chemical fiber industry to complete the full drafting process of fiber,is one of the key components of spinning fiber combined machine.The temperature stability and uniformity on the godet surface of the heated draw roll directly affect the quality of the chemical fiber drafting. The types and performance of the heater, structure and material quality of the heated draw roll and mode of uniform heat has a relationship with the temperature uniformity on the godet surface.The temperature stability on the godet surface is determined by temperature measurement precision and control performance of the temperature control system.High-speed rotation of the heated draw roll in procession of work increase the difficulty of the temperature measurement and transmission.Heated draw roll,as a temperature control object, has the characteristics of large pure time delay,inertia constant,complex nonlinear and time-varying,so it is hard to establish a precise mathematical model. The uncertainty,such as variable parameters and variable structure,caused by the working condition and the environmental impact, resulte in traditional temperature control methods hard to meet the production requirements.This paper researchs and designs a kind of new intelligent temperature control system of heated draw roll to achieve accurate temperature measurement and control optimization.Rotary temperature transmitter solves the measurement and transmission of the temperature of the high-speed rotating part based on technology of non-contact power supply and infrared data transmission. By using multi-polar magnetic ring and hall element,rotary temperature transmitter can simultaneously measure the speed of heated draw roll while measuring the temperature.Thermostat is designed based on C8051F MCU and can control two roller at the same time.In order to guarantee the stability and anti-interference ability of the thermostat, effective isolation is taken between input and output signals and power supply. PID expert controller is used in the temperature control system and can adjust the temperature intelligently under different setting temperature,speed and ambient temperature by constantly enriching and refining expert knowledge base.The results show that the system is safe and reliable,has strong stability and anti-interference ability. Temperature measurement range is-40-300℃,temperature resolution ratio is0.1℃and temperature control accuracy reaches0.3℃. PID expert controller exhibits good control performance,the overshoot is less than1.5%and the adjustment time is less than8minutes.