Protocol requirements for remote operation of a substation on Abu Dhabi power system

Computer based substation control system (SCS) has now dawned on the Abu Dhabi power system to perform monitoring and controlling of all transmission class substations built by Abu Dhabi Water and Electricity Authority (ADWEA) in recent times. SCS is now performing at many remote outlying substations a broad range of process activities with a multilevel architecture, a distributed intelligence and a duplication of major hardware and software devices. In this computer based control design, the level-3 control of all SCS stations is performed from the load despatch centre (LDC), which is set to exchange all digitally encoded messages over serial data communication channels. The data communications technology took off for power utility applications with a great multitude of proprietary communications protocols. However, users soon began to appreciate the need and power of a publicly agreed, industry proven, widely used and available standard protocols for ensuring complete vendor interoperability, and put major emphasis in the project specifications on the supply of SCS equipment with standard communications interfaces. As a result, support for the open system protocol has become widespread, and for utility system applications, the IEC 101 standard protocol begins to offer a ubiquitous service, resulting in the gradual demise of the proprietary networking architectures. This paper discusses the concept, design, engineering and testing of an IEC communication link developed to verify level -3 control of a 132 kV substation from LDC.