SYSTEM FOR CONTROLLING THICKNESS OF PLASTIC SHEET FILM BY VARIABLE P-CONTROLLER, WHICH IS RELATED TO AN ACTIVE VARIABLE PID CONTROLLER

摘要

PURPOSE: A system for controlling the thickness of a plastic sheet film by variable P-controller is provided to more effectively compensate the error of thickness range of the plastic film by using the variable P-controller. CONSTITUTION: A system for controlling the thickness of a plastic sheet film by variable P-controller includes a variable P-controller(1), a PID temperature controller(2), a die(3), a film thickness measuring unit(5), a temperature sensor(6) and a sheet thickness measuring unit(7). The system for controlling the thickness of a plastic sheet film is characterized in that the variable P-controller(1) is applied to the external film thickness control loop(9) at the cascade double control structure of the plastic sheet/film thickness control system and includes the parameter factor to amplify the absolute value of the error changed in response to the time.