Application Of Fuzzy And Predictive Control In The Control Of Vacuum Tower

Atmospheric and decompression systems are the most important devices for petroleum refining companies,and their crude oil production efficiency and refining capacity have an important impact on the economic efficiency of enterprises.Many uncontrollable factors,such as non-linearity,hysteresis and correlation,will be encountered in the production control process of the atmospheric and vacuum decompression,resulting in the control system cannot accurately control the production process.In view of the limitations of traditional PID control,this paper uses the fuzzy predictive control method to improve.Firstly,fuzzy control is an intelligent control method.This method can better solve the problem that the controlled object is not easy to build the mathematical model.Then,the predictive control is also an intelligent control method.This method solves the control by predicting the possible deviation in the future process.The lag problem encountered by the controlled object during the process.Therefore,the combination of fuzzy control and predictive control to form fuzzy predictive control can effectively solve the problem that traditional control is difficult to handle.This paper selects the decompression section of the atmospheric and vacuum devices as the object of the simulation test.The fuzzy predictive control is applied to the control of the temperature of the top of the vacuum tower,the temperature of the vacuum tower bottom and the outlet temperature of the vacuum furnace.And the two-input dual-output decoupling simulation experiment was performed on the temperature of the vacuum tower top and the temperature of the vacuum tower tower,and the model of the pressure reduction device was built in Simulink and simulated.The comparison between the simulation results of the fuzzy predictive control and the traditional PID control in this paper shows that the fuzzy predictive control has a very good control effect and can solve the strong coupling problem in the control process of the atmospheric and vacuum devices.The fuzzy control and predictive control are applied in the actual vacuum rectification operation training device to monitor the control effect,and then to explore the experimental results of fuzzy predictive control.In the course of the test,it will be difficult to detect and control the tiny flow of the training equipment.A series of reform measures have been carried out to solve this problem.For example,the optimization of operating process conditions,the use of an approximately unsteady flow equivalent steady-state flow method,and the selection of suitable sensors to detect small variable parameters in the device.The test results show that the fuzzy predictive control is much better than the traditional PID control.Finally,based on the above experience in the operation and control of atmospheric and vacuum installations,a rectification experimental device with poor equipment performance,uneven temperature distribution in the tower,large detection error,and unsatisfactory control effect has been effectively modified in the laboratory.After the transformation,the detection and control of the equipment are satisfactory.