The Development Of Front-end System In Distributed SCADA/DMS

The research on front-end system of distribution automation has great practical significance. It can promote the integration of distribution automation and the widely use of intelligent RTU equipment in distribution management system (DM5). According to the ISO/OSI seven layer reference model, the characteristic of serial communication network in distributed SCADAIDMS is analyzed. Some familiar remote protocol in the field of electrical power are listed in this paper. Through the introduction of DNP3.O, the remote protocol which has open architecture is discussed in detail. Considering the feature of distribution system, a front-end system which is made up of PC and internal intelligent interface cards is developed. The interface cards have their own CPU which operates independently from the PC. The PC deal with net data exchange with other computers on the Ethernet based on TCP/IP protocol; the interface cards responsible for the communication between field RTU and the front-end system. They work simultaneously and exchange data through a dual-port SRAM according to the internal communication protocol. This structure gives more efficiency, reliability and flexibility to the front-end system.