Research And Design Of The Screw Press Control System Based On PLC

The traditional screw press are used to squeezing vegetable oil. However, the traditional screw press have many disadvantages,such as the degree of automation is low level, the quality of oil is low. Giving these disadvantages, By full research on the screw press oil principle, mechanical structure of the screw press and the control that related to the theory of screw press, Moreover, It is discussed several key factors that the influence about the oil quality and the production efficiency of screw press.It is designed a set of screw press automatic closed-loop control system, The control system used to control the inside temperature of the pressing chamber and the speed of spindle, and simulated the control system, The simulation results show that: The system has fast response speed and short adjusting time. the degree of automation of the screw press is greatly improved, the squeezing chamber press temperature and press force has been effectively controlled, the control system has strong anti-interference ability, It is a kind of control system for spiral oil press suitable for actual production.The key problem of control system of screw press is: the production efficiency and the quality of oil. How to guarantee the quality of the oil firstly, as far as possible to improve the production efficiency of screw press, is a difficult technical problem of spiral oil press machine control system. Aiming at the problem, building the automatic control system based on PLC. This paper has done the following work:Firstly, It is analyses the key factors that the influence about the oil quality and the production efficiency of screw press, combined with the methods and the control related the theory of screw press, formulate the overall control scheme, the spiral press temperature control scheme and spindle speed control scheme.Secondly, According to the control requirements and the hardware selection method, It is selected the screw press control system hardware, including the PLC controller, the frequency converter, the temperature sensor, the heater and the cooling method and so on.Thirdly, the controller PLC is connected with the inverter and communicating each other, the communication program is developed. It is designed the PID controller and fuzzy PID controller. Compare to the simulation results, determined the temperature control with PID control algorithm, It is designed the PID controller parameters, optimization the parameters of PID.Finally, Combined with the actual situation, It is designed and analysisthe reliability of the control system, Improves the stability and reliability of the oil press machine.