Research And Design Of Plate Tachometer PID Temperature Control Box Based On Genetic Algorithm

Plate cylinder is the most important part of a printing press.it requires a very high degree of external demand when working.Even slight errors can adversely affect the quality of products.When the temperature of the plate cylinder is too low,the viscosity of the ink increases and the thixotropy decreases.These changes will cause the adhesion effect during printing to be greatly reduced,and it is extremely easy to smear the product.The temperature change of the circulating water in plate cylinder is a complicated process,which belongs to a time-varying and time-delay system.Therefore,traditional PID control is often difficult to find correct parameters,which will lead to bad control results.As an algorithm to find the optimal solution,the genetic algorithm simulates survival of the fittest in natural environment and from generation to generation to find the approximate optimal solution.Thus,the combination of PID control and genetic algorithm can effectively improve control effects.This paper designs a new type of temperature control equipment after investigating the temperature control system of plate cylinder and analyze the defects of delay,non-linearity,and susceptible,which has the advantages of high precision and good stability.In order to find accurate control parameters in complex system the new control equipment improves this defect by using genetic algorithms to optimize the PID control parameters.Through fitness function,the appropriate control parameters can be found quickly and accurately,which overcomes the disadvantages of traditional PID controller such as large workload,low accuracy,and long time-consuming when setting parameters.This paper further optimizes the genetic algorithm and improves the possible early convergence and premature convergence.In the PID control,the incremental PID control algorithm is used.The simulation results show that combining of genetic algorithm and PID control makes the system have the characteristics of small overshoot,fast response and good steady state performance.According to final results,the new system is far more outstanding than the old one.The control system of this article adopts Omron C200 H PLC,adding the temperature control module that realizes the monitoring to the temperature.Through the auxiliary circuit to control the three-way valve,heating the precise control of the temperature signal acquisition/conversion.In the part of HMI design,realizing the communication with the Omron touch screen NT631 C,which improves the operability of the system.At the same time gives the status of the system operation back to the user.The system has been successfully put into production right now.Based on feedback and product quality,it not only greatly improves work efficiency,but also has a positive impact on energy conservation.