With grid control aspects of Grid Modernization, there are several systems that are fundamental to evolving the grid. The back office for a Modernized Grid in essence becomes a system-of-systems which includes an Advanced Distribution Management System (ADMS), a Distributed Energy Resource Management System (DERMS), an Optimization System, an updated Historian, Short-Term Forecasting and bus infrastructure to communicate between the different components.
ADMS is a solution which merges the functionality of SCADA, Distribution Management Systems (DMS) and Outage Management Systems (OMS) to provide a more comprehensive integrated view of the grid for system operations. In some solutions DERMS is also included, but we will present this separately since it represents new functionality for most current utility operations. The ADMS provides functionality which spans these systems, including Fault Location, Isolation and Service Restoration (FLISR), Volt/VAR optimization(VVO), Voltage Regulation, two-way Power Flow management, Outage management, system monitoring, switch management, crew management, etc.
Very often ADMS systems are simply constructed by vendors cobbling together their own disparate subsystems with some proprietary bus infrastructure and rolling it out as a new ADMS. Of course this leads to common issues with integrating multiple systems; separate databases, very different architectures for each subsystem, no common set of terminology, no common integrated view, limited extensibility, only portions of the solution included in training, etc. To combat these limitations, ADMS vendors should consider providing the necessary functionality with more modular and extensible systems. These new ADMS systems should enable the distribution and mobility of operations and personnel while bringing together data from the different subsystems and allow it to be analyzed and presented in an integrated and consistent form.
Nowhere is this more evident than in GIS and grid connectivity information. Today, this data is managed in each of the subsystems, yielding their own particular view of the grid. This requires that critical updates to connectivity must be maintained and synchronized across all of the subsequent subsystems. Although this does not present a difficult challenge for most grid operations today, as the number of field and edge devices grows, and the need for more real-time access to the state of the grid increases, this will become an increasingly complex problem. Mis-alignment and synchronization failures could potentially lead to problems in reliability and safety.
These issues point to the need of a centralized connectivity model, which is available not only to the subsystems of the ADMS, but to the other systems within GridMod. This connectivity model should provide a common data abstraction layer allowing for more historical information to be requested as well as subscribing to real-time changes in the grid model. It should support maintaining, as-built, as-operated, as-planned, as-designed, etc. views, from a centralized common source.
Another area of extensibility for ADMS is the integration of AMI into operations. Although outage information is already used by many OMS systems, bellwether-based voltage data could also be integrated. Bellwether meters could provide data throughout the day, essentially using the meter as an added sensor on the distribution grid (This has additional complications with how time is managed across an AMI and ADMS system, which will be covered in a later blog).
These are two simple aspects of ADMS that could be considered for the next generation systems, although there are many others to be explored. With Grid Modernization, the traditional views of DMS and OMS are expanding and silos of information and resources need to be integrated to support more comprehensive and real-time information processing and presentation. As more grid devices are deployed and much more real-time information is available, ADMS systems will need to become more automated and provide more aggregate views of the grid. Finally, as DER proliferates, DERMS will need to become more tightly integrated with ADMS and operations to better manage an increasingly complex distribution grid. DERMS will be covered in a subsequent blog.