Researching And Developing Multi-point Temperature Control System Of Industrial Resistance-furnace

Heat-treatment is an important method to improve the quality of metal materials and their products. With the development of industry in recent years, the performance requirements of metal materials are becoming more demanding. The heat-treatment technology tends to be of high-quality, efficient, energy-saving and environment-protecting. The furnace is the common heating-equipment of heat-treatment production and widely used in our country. It's the typical control object in industrial process with the characteristic of unidirectionality for temperature rising, major sluggishness, varying and etc. The vast majority of traditional furnace temperature control systems are built on the base of models. It is difficult to guarantee requirements of heating technology. The rising and keeping in temperature depends on the working current of SCR; the dropping depends on environmental temperature. As the temperature goes beyond the scope, there is no control method to drop it. So it is very difficult to build the accurate model and definite parameter by mathematical methods. It is hard to achieve the ideal result through the traditional control theory and method.This article points out some main problems on measuring and controlling temperature and introduces the research progress of the temperature control system at home and abroad by analysing the heating process of "RJ9" well resistance furnace. Aiming at special heating requirement of industrial resistance-furnace, the article analyses all kinds of variables which affect temperature changes. By comparing PID, Dahlin algorithm, Smith predictor and fuzzy control, a fuzzy control method with segment integral link is presented to control the temperature of industrial resistance-furnace. A fuzzy controller is designed. It is applied in the control system of resistance furnace and meet the requirement of the stability of temperature control. The hardware and software of temperature control system of industrial resistance-furnace is developed by MCU technology. This system has adopted anti-interference measures and completed test, realized multi-point temperature control. By transforming the production process of industrial resistance-furnace, production technology is optimized, the quality of products and management level are improved, and cost performance of the control system is quite good.By the practical motion, this system has not only increased the automatic level of factories and also saved energy, as well as improving working conditions, realizing information sharing while the items are putting into effect, the quality of product is assured, as a result, it will bring about distinct social and economic benefits...