Research On Distributed Control System Of Batch Dyeing

For the purpose of the automazation and informazation of production and management indyeing enterprises，this thesis took batch dyeing machines as a research object, reviewed theresearch situation of batch dyeing equipment, techniques and process automation at abroad anddomestic, analyzed the requirements of dyeing process and the technical conditions to realizebatch dyeing distribution control, and proposed a technical scheme of distributed control whichcombined the centralized management of batch dyeing equipment and decentralized control ofbatch dyeing process. The proposed control system consists of four layers in which theproduction management layer achieves the centralized management and monitoring the dyeingmachines, the process control layer which consists of dyeing machine controllers connected tothe internet fulfill decentralized control of dyeing machine, and the field execution layer whichconsists of intelligent sensors and actuators connected to fieldbus implements the dataacquisition and implementation of dyeing field.Contributed to a project of dyeing machine centralized control system carrying out inHangZhou KaiYuan Computer Technology Co.Ltd, this thesis researched the technology andmethod of Ethernet communication between production management layer and process controllayer and the technologies of RS485bus communication which implements MODBUS protocolbetween process control layer and field execution layer. The design and development of a dyeingmachine controller which has the standard TCP/IP protocol interface and the functions of dyeingand parameters setting, dyeing-program edit, historical data saving and uploading, real-time dataacquisition and monitoring etc were presented in this thesis. The intelligent temperature sensingmodule in which the RS485network interface was built changes the method of temperaturesignal transmission from the traditional way of analog signal with1-5V or4-20mA to the network digital signal. This state of the art design not only makes the field signal transmissionmore stable but also cuts down the required quantities of cables and the connectors. Taking thedyeing temperature control as an example, the realization of centralized management of batchdyeing machine and dyeing process parameters decentralized control through utilizing thedistribution units of temperature sensors, liquid level sensors, the electric valve actuators wasdescribed in particular.The research and development of the Batch Dyeing Distributed Control System(BDDCS)presented in this thesis provides an effective solution for solving the existed problems on theproduction efficiency, quality and management infomazation due to batch dyeing machines’characteristics of multi machines and small quantities in production. The results of the teststhrough network show that the features of control function, management and networkcommunication abilities of BDDCS can satisfy the enterprises’ requirements in real time controland management informazation, the intended purposes were achieved.