IEC TC57 Working Group 17 (Power system intelligent electronic device communication and associated data models for microgrids, distributed energy resources and distribution automation), responsible for IED communications, data models for microgrids, distributed generation and distribution automation, has held its kick-off meeting on a new work item. The subject: a set of use cases for IEC 61850 in data centre infrastructure.
Three Levels of Application
The work is structured around several categories of use cases.
Power supply. The first and most obvious scenario is classic protection, automation and monitoring of the data centre electrical network, regardless of voltage level. IEC 61850-compatible devices are well established at medium and high voltage and are widely used in data centre power systems.
Standby power switching. In simple cases this means switching between redundant power feeds; in complex cases it involves multi-step switching sequences similar to open-ring radial feeder management in distribution networks (as described in IEC 61850-90-6). Data centres are critical loads, so the reliability of automatic transfer switching schemes and continuous UPS monitoring are essential.
Cooling systems. The third area covers monitoring of heat rejection systems, including air and liquid cooling. IEC 61850 already includes data models for fans and pumps in power transformer cooling systems, but these will need extension for the data centre context. The task force plans to build on work done for IEC 61850-90-3 Edition 2 — the standard defining comprehensive models for transformer cooling systems, including the relationships between control systems and individual fans.
Generation, Storage and the Grid
Modern data centres frequently include on-site generation and energy storage. The data models of IEC 61850-7-420 (distributed energy resources and storage) and IEC 61850-7-410 (thermal power plants) may be used to describe these systems.
A further set of use cases relates to the impact of data centres on the external grid. Data centre operators are increasingly aware of their influence on sub-transmission and even transmission networks. Power supply contracts increasingly include obligations to manage load during severe weather events or contingencies. This implies a new class of tasks: demand management, load curtailment or transition to islanded microgrid operation. IEC 61850 can provide the underlying monitoring and control of electrical, cooling and other systems, while pricing information is used by the client SCADA as part of its optimisation strategy.