Control Design On The 75t Gas Boiler Drum Water Level In Xingtai Iron And Steel Co., Ltd.

At present, the iron and steel enterprises will produce a lot of blast furnace gas in the production process, these gases to the atmosphere not only if the bleeding is not conducive to environmental protection, but also a waste of energy or. Blast furnace gas by burning can produce a lot of heat value of gas boiler, these can be heat through the drum into promoting the steam turbine mechanical energy, and thenconverted to a more convenient use of electric energy. Boiler is a kind of special equipment, stable operation of critical it. In the control process of boiler in the boilerdrum level, must be maintained in a certain range. Control of drum level is a difficult problem in the boiler control, the traditional PID control is based on the mathematical model of the controlled object to control, and the boiler is a complex system, it has nonlinear, uncertainty and time delay characteristics, it is difficult to establish a mathematical model for it. So the conventional PID control is difficult to meet the control requirement,the control effect is not ideal. Control method at present more popular is the cascade three impulse PID control, the introduction of steam drum water level, water flow and steam flow as the three impulse, to solve the "false liquid level control problem" brought. But due to the current iron and steel form general downturn, blast furnace production, limiting the production of frequent occurrence,and the boiler body aging and other factors, led to the pressure of blast furnace gas flow, extremely unstable, the combustion system of the overall control quality declining, in order to maintain quality control often need to adjust the parameter of PID controller, not only the human cost, but also affects the the normal operation of the production.75t gas boiler control system in Xingtai iron and Steel Co. Ltd. were studied, the drum water level status report on this important monitoring and control parameters, and the gas boiler technology and control process were investigated, meanwhile combining the actual production needs, the establishment of mathematical model of boiler water level control characteristics, fuzzy self-tuning PID control system by using three impulse feed forward cascade control system and fuzzy controller combined, form the effective control of drum water level. The control method was improved to overcome thein fluence of the parameters are difficult to adjust, improve the control precision, has achieved the anticipated target, and captive power efficient power generation usingand the whole boiler system safety, stable operation, normal basis.