Development and implementation of a digital control system for a former-vulcanizer

When modernizing the control system for the tire vulcanization process at CJSC «Voronezh Tire Plant», it was necessary to ensure control and regulation of technological parameters, as well as control of the vulcanizer equipment based on a control controller. The structure of an automated control system was developed, temperature and pressure sensors, an actuator, input and output modules, as well as a SIMATIC S7-1500 control controller were selected. A project for an automated workstation for a vulcanization section operator for the SIMATIC 6АV6647-0АF11-3АХ0 touch panel was developed in the WinCC environment. As part of the project, information data channels were formed, mnemonic diagrams of tire vulcanization units were developed, logical dependencies for picking up and moving tires were implemented, as well as an algorithm for digital control of the temperature of the slabs during vulcanization (the controller programming was performed in the TIA Portal environment). At the same time, information about completed operations is archived, and emerging emergency situations are recorded. A synthesis of an algorithm for digital cascade pressure control (an intermediate controlled parameter) with steam flow with correction for plate temperature has been carried out. The settings of the digital controllers of the internal and external loops were calculated using optimization programs using the numerical gradient method according to the criterion of minimum integral-square error based on the discrete dynamic models of the channels of the control object obtained as a result of identification (according to experimental acceleration curves). Calculation using models showed a higher efficiency of the cascade control algorithm compared to a single-circuit scheme for stabilizing the temperature of the plates (temperature fluctuations during regulation decreased by 5-7 °C). The system has been put into operation.