The Multi-Application and Implementation of Auxiliary Control Network in Power Plant Desulfurization Systems

With the development of industrial control and network communication technologies, the Programmable Logic Controller (PLC) used in communication network plays an increasingly important role in a gradually complex and large-scale industrial automation. Rockwell Automation introduced a number of fully functional network communication systems, whitch applied to a variety of industrial automation networks. Ethernet network, Controlnet network are the main Rockwell productions, accomplish the inter-network communication.The task of this article is the application of Rockwell Automation AB-PLC control system used in power plant desulfurization systems, the design ideas and specific methods of the power plant flue gas desulphurization system network.The main work of this paper include the following:First, this article introduces the basic knowledge of network communication technologies, including an overview of network communications, communication system models, communication modes, quality assessment and knowledge-based industrial control LAN.Second, this article introduces the Ethernet network, Controlnet network, DeviceNet network architecture, network protocols, network functions and communication implementation methods.Third, the network architecture, network protocols and network functions of the AB-PLC three-tier network(EtherNet network, ControlNet network and the DeviceNet network) used in desulfurization system were demonstrated in detail. design of network architecture and process structure for the desulfurization system were designed after the analysis of system design goals and process requirements the desulfurization system was developed by the Rxlink software in the PC-side. The ControlNet network, the PLC DeviceNet network subsystem, the operating parameters and the field data are monitored by the PC network via EtherNet. After the actual site,the efficient of the desulfurization system is more than 96%, the system is more stable, and the desired results were achieved.This research will enhance the awareness of the application of communication technology in the field of industrial automation.After a variety research of on-site communication network protocols, we designed the most suitable network architecture for desulfurization system. Meanwhile, the desulfurization system runs successfully for the reduction of emissions of sulfur dioxide, controlling the sulfur dioxide air pollution, protection of air quality.The research shows very important social and economic benefits.