Leading Advancements in Interoperability
Open Field Message Bus (OpenFMB™)
Interoperability between devices, systems and applications is important for several reasons:
- Industry-changing activities such as distributed energy resources (DER), microgrids and advanced demand response (ADR) require disparate field devices to work together remotely with little delay.
- It is key to the operation of a more efficient, cost-effective and secure grid. Successful interoperability allows utilities to leverage existing grid network infrastructure and underutilized assets.
- It reduces the effort in device configuration, management and commissioning.
- The expected and growing implementation of DER and microgrids will require distributed analytics and operations. Equipment and application interoperability will gradually reduce the hidden costs and inefficiencies with siloed, single-function solutions through the use of an OpenFMB.
What is OpenFMB?
OpenFMB is a reference architecture and framework for allowing distributed intelligent nodes to interact with each other. These nodes manage distributed resources that communicate via common semantics and federate data locally for control and reporting. The benefits of OpenFMB include:
- Supports field-based applications that enable scalable peer-to-peer publish/subscribe architecture using distributed logic as well as centralized logic.
- Data-centric rather than device-centric communication including support for harmonized system and device data.
- Reduces latency and creates distributed intelligence opportunities to manage local grids in the most efficient way based on local resources and conditions.
- Enables grid devices to speak to each other, e.g. meters, relays, inverters, cap bank controllers, etc.
- Allows legacy equipment to be retrofitted for new capabilities, features, and extended life.
- Facilitates data integration across previously siloed domains within the utility. Standards for OpenFMB are being developed through SGIP, and led by utilities (largest IOU, Muni and Co-op) based on their priorities and interoperability demonstration experience. It is important to the utility industry for several reasons:
- Accuracy: Provides accurate control and alleviates intermittency of distributed energy resources
- Scalability: Provides the ability to scale independently, as needed, without needing a system wide rollout
- Reduced Costs: Takes cost out of the business by reducing integration time and effort
- Security: A distributed grid is more resilient and can be made more secure
Duke Energy is proud to be an innovator and participant in SGIP with the development of OpenFMB standards. The results of these efforts are in operation at our Mount Holly facility.
CoalitionWe enacted the first utility-owned OpenFMB reference implementation with our Coalition. At our newly constructed microgrid test bed in Mount Holly, N.C. we not only demonstrate plug-and-play integration of innovative solutions from our partnering vendors, but we also showcase low-latency microgrid optimization and seamless islanding use cases using a variety of wired and wireless communications technologies that leverage open Internet of Things (IoT) publish-subscribe (pub/sub) protocols and industry-standard data modeling structures based on IEC’s Common Information Model (CIM).
Additionally, all work from our Coalition will be shared with the industry, providing access to lessons learned on field interoperability and ultimately leading to extensions and expansions of the OpenFMB standard with new use cases (e.g. DA, AMI, DR) and additional data models (e.g. Multi-speak, 61850).
ResultsThe Coalition has demonstrated there are alternative ways to achieve enhanced microgrid operations. Our Mount Holly microgrid test bed exhibits a diverse set of technologies that all communicate in the data distribution service (DDS), message queue telemetry transport (MQTT) or advanced queue message protocol (AMQP) open IoT pub/sub protocols, including the following assets:
1. 100-kW PV solar system with smart inverter capabilities
2. 250-kW battery energy storage system
3. 10kW solar carport with EV charging capabilities
4. 500-kW automated resistive load-bank
5. Instrumented and automated distribution grid equipment, such as reclosers, smart meters, sensors and PMUs
6. Wireless devices, supporting Wi-Fi, 4G LTE, 900 MHz RF and AMI Mesh
7. An envision room with appliances and smart breaker monitoring and control capabilities
8. An operations room with commercial application software to monitor and control the microgrid components
This project has offered a transferable test harness and validated baseline for the upcoming utility test beds, at CPS Energy, Southern California Edison, Detroit Edison, EPRI, NREL, Oak Ridge Labs and other utilities and national labs that plan to implement the OpenFMB reference architecture.
- Installation and operation of the microgrid using the OpenFMB reference framework is providing Duke Energy with valuable data and insights to further develop the economic and operational value of distributed intelligence in distribution grid operations.
- Some existing technologies and applications that were incorporated into the project did not initially produce the information needed to run distributed applications. They were originally designed to be run from a central source/application.
- Distributed activities need to be choreographed, especially with equipment and applications running at the millisecond level. Specifically, due to communications and application latencies, equipment did not operate in the proper sequence.
- Time accuracy and synchronization become paramount when running microgrid operations. A major challenge we had to overcome was ensuring the key equipment and applications ran off the same time stamps. This was particularly challenging for operations requiring multiple pieces of equipment requiring millisecond response times.
- Accuracy of sensing equipment becomes more important at the distribution level with microgrid operations; Phasor Measurement Units (PMUs) are available in common distribution grid devices to collect granular information not typically used such as phase angle and frequency measurements.
- Many issues discovered during the Mount Holly microgrid solution installation and testing were hardware-related, specifically challenges with using them for microgrid and distributed grid operations. In many instances, these issues were discovered through the use of OpenFMB enabled applications.
- The diversity of skill sets and experiences from the Coalition partners provided multiple learning opportunities and insights, which helped us refine our solution and information that ultimately ended up in the OpenFMB reference framework.