| In order to build a resource-conserving and environment-friendly harmony society, steel plants have been using coke oven and blast furnace gas produced in the production process to generate power. Due to technical, safety and cost reasons, mixed-gas regulators are currently large pneumatic pressure control valves. Because the lagging characteristics of the pneumatic executive system, the impact of gas compressibility, large pneumatic pressure control valve can not adjust in time, and pressure fluctuation of the mixed gas sent to the gas turbine is too large, which are the main reasons for abnormal power generation. It is a key technical issue to develop high-performance pressure control valve used in power generation projects for steel plant.The main problems for large pressure control valve are lag and slow in response, which the pneumatic part can not overcome. Electro-hydraulic executive system has strong capability for resisting bias, further more it can output large thrust and faster execution speed. In the paper, subject bring forward that using ressure control system drived by electro-hydraulic proportional unit to replace the pneumatic pressure regulator system currently used in steel cycle power generation project. In this paper, firstly, system is designed and components are selected. Secondly, physical model was build based on graphical modeling, and PID control mode of system modeling based on the simulation software AMESim is established, further more simulation analysis for dynamic response is carried out. Greatest degree details of the system can be considered in this method, and more accurate system model is able to be built. Thirdly, the mechanism of modeling, that is, through analysing the force balance equation and characteristics of the pressure-flow characteristics of every part to establish a non-linear mathematical model. Finally, in order to improve the response speed, accuracy and stability, pressure control strategies are studied based on Matlab.After study and analysis of simulation results on large flux mixed gas control system, we can see that after the using of the PID control method for large-flux mixed-gas control system, the system can track the input signal perfectly by adjusting different proportion, integral and differential coefficient to the system, and is able to control the output pressure in the range expected essentially. But not very good ability to overcome the pressure fluctuations act on stability of the system. After the using of fuzzy control, the adverse effects that external fluctuations act on the system have been reduced, and the stability of the system is improved. Adaptive capacity to uncertainty factors is enhanced also.
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