The Research And Design Of Control System For Limekiln

This project comes from the new building of limekiln control system in HeFei Iron and Steel Co., Ltd. The control system uses computers and PLC to analysis data and control production. This system can control the calcinations zone temperature of limekiln in order to produce active lime that fits to metallurgy.The calcinations zone temperature is the control aim in the control system of limekiln. We can adjust the ratio of the gas flow to air flow to control it. The limekiln system is a time-variable system and strong disturbance exists in it. We can not get a good effect with PID control only, so the fuzzy-PID control is introduced in it.The key to control system is the design of controller. This essay introduces in detail fuzzy controller's structure principle, its characteristics and design principle and compares strengthens and weakness of several kinds of control calculation. By using fuzzy PID controller, which can arrange automatically, this system can achieve a more satisfactory effect.The production control system for limekiln realizes functions of automatic trouble-locating and automatic control of material-adding system, temperature-controlling system, supervisory system and alarm system. Because there are not many measuring and supervising points in the whole limekiln in this system, limekiln control system is made up of a computer and a Simens S7-300PLC.If only PID Control is used in the limekiln temperature-controlling system, the effect is not same and maybe not fit the demand of control when the parameters of limekiln system change. In the limekiln manufactures process, if we use compound PID Fuzzy control system, deviation E and changes E of the calcinations zone temperatures of limekiln as input language variables and changes of gas flow as output language variable. After Mat lab simulation, it was concluded that the Fuzzy Control used in temperature control system of limekiln could get a more satisfactory effect and better.