A Serial Communications Interface for Microprocessor-Based Power Distribution Apparatus

A standard set of distribution automation protocols must be defined to eliminate system incompatabilities. Present protocols are usually based on one of the many outdated SCADA protocols. This paper describes a communications interface for use in power distribution systems apparatus control and coordination in terms of the ISO-OSI reference model. An automated distribution control and communication architecture is defined utilizing a dispersed intelligence concept. Existing ISO-HDLC and EIA-RS422 standard protocols are used to define the link and physical layers for device control computers (DCC). The session and presentation layer protocols are discussed with respect to an existing microprocessor-based DCC. The hardware and software details of a specific implementation of this interface are also illustrated.