IEC 61850-compliant equipment can be quickly configured using Substation Configuration Language (SCL), a descriptive, XML-based, human-readable programming language. "It contains every single action of every single component in the substation," Smith said. "The driver for this comprehensive digital representation stems from the primary IEC 61850 schema, which calls for complete and rapid communications among all levels of equipment and control, especially at the substation, where high voltages are transformed to low and then sent out on the distribution grid. This process demands interoperability and protection, monitoring and metering functions—delivered in as automated a fashion as possible."
In the smart grid world, substation protection relays are replaced by more flexible and multi-functional IEDs that can respond to situations in milliseconds and send data via multiple paths to higher-level equipment. "There are wheels within wheels," Smith said. "Conventional Ethernet transmissions go through a conventional TCP/IP layer, but the same data can travel directly via ultra-high-speed communications. The alternate data paths are there to handle all contingencies. You don’t want a failure-to-act to be triggered by a network delay."
"In the IEC 68150 world, client functions listen to the net, gathering and keeping tabs on what is going on," Smith said. "A server function sends all the messages—some being very special kinds of messages that control devices and others with reports, all in high speed. Devices can contain both client and server. For example, our SCD-5200 Power RTU functions both as server and client.
"We offer two key licensed development environments. On the design side, the Substation Automation Configuration product provides the highest level configuration management," Smith said.
This high level product contains the development platform (the InFusion Integrated Design Environment) and SCADA Industry Objects—the latter, a fit-for-purpose SCADA application module. Under that module are IEC 61850 Device Objects and IEC 61850 Substation Objects, which contain all the configurable and controllable functions, as well as built-in constraints to prevent non-compliant designs. Output is automatically generated in SCL.
There is, in addition a Designer Product, a low-cost tool for designing components within the substation system for use by specialist engineers (for example, the protection engineer) in the design of specific functionalities.
"It’s a beautifully balanced and easy-to-use design system," Smith said. "By capturing and embedding all applicable constraints in the objects themselves, engineers are freed to configure devices quickly and accurately."