Design On The Control System Of Sebacic Acid Feed By The PCS7

In the current industrially process of producing sebacic acid, oleic acid hydrolysis of sodium hydroxide and castor oil in accordance with a certain proportion into the cracking vessel. Inside the cracking, vessel a series of chemical reactions cause under the influence of a certain temperature, pressure and catalysts. Then, the sebacic acid will be achieved. The key to the success of the product process lie in the ratio sodium hydroxide and oleic and control the reaction temperature and mixing motor current.The traditional control process is performed by PSC7. In the system, the inventory of the sodium hydroxide and castor oil is controlled by two proportional cycles. In this method, some automation functions are achieved. However, the parameters in the PID are very hard to obtain. It leads to the unstable of the system, i.e.when the disturbance is large, the control system will lose its performance.In the improved system with fuzzy control theory, the reaction temperature and mixing motor current as the input of the system, and the regulating valve for sodium hydroxide and castor oil as output. The software of the proposed system is still based on PCS7, and the product process is monitored by WINCC.In this paper, in order to control a large inertia, nonlinear characteristics of pure lag reactor, using a fuzzy self-tuning PID control. The controller has good adaptability,robustness, low overshoot and faster reaction speed. Test results show that the precision reliable, high stability, and achieving the requirements of the subject with a higher value.