MIRACL: Microgrids, Infrastructure Resilience, and Advanced Controls Launchpad
MIRACL is a collaborative multi-year distributed wind research effort to accelerate distributed wind technology development into the expanded distributed energy future.
Distributed wind experiences many of the same deployment and operational challenges as wind deployed at the bulk-transmission scale. Controls, communication, and hardware for grid and microgrid integration of wind energy technology with other distributed energy resources (DERs) are not well developed or standardized. To address the concerns of the industry, and support development of useful case studies, the MIRACL effort aims to:
- Improve and validate capabilities of wind technology, at all scales, to integrate
in a seamless "plug-and-play" manner with other technologies into microgrids through
coordinated and secure controls and communications protocols
- Conduct the research, testing, and standards development to ensure that distributed wind technology can play an active role in high-renewable-contribution, distributed energy-driven grids of the future.
The U.S. Department of Energy (DOE) Wind Energy Technologies Office and NREL initiated the Microgrids, Infrastructure Resilience, and Advanced Controls Launchpad in 2018 in response to a request from the distributed wind industry to improve the operation, integration, and valuation of distributed wind in transactive environments, microgrids, and distribution system networks. Read the DOE MIRACL fact sheet.
NREL is leading the collaborative MIRACL team between NREL, Idaho National Laboratory, Pacific Northwest National Laboratory, and Sandia National Laboratory. To drive collaboration, MIRACL research areas are led by a single laboratory and each research area is a collaborative effort aimed at most effectively using the best available expertise and infrastructure from all four of the national laboratories.
Primary Research Areas
- Valuation and Modeling
Pacific Northwest National Laboratory is leading efforts to improve valuation of grid system contributions from wind as a DER and accurately represent distributed wind in models.
- Advanced Controls
NREL and Sandia National Laboratory are collaborating on advanced controls for wind-hybrid DER systems.
- Resilience and Cyber Security
Idaho National Laboratory is leading the work package of advanced resilience valuation and cyber security threat mitigation for distributed wind.
In MIRACL and other distributed wind research, use cases will span the wide variety of distributed wind projects and be the basis of MIRACL discussions and targeted work packages. Distributed wind projects will be categorized into use cases with similar technical (interconnection, certification, integrating with other renewable energy systems, etc.), financial (cost structure, valuation), market (developer, owner), resilience (energy security, cyber security, fuel diversity, financial security) requirements, challenges, and benefits. The high-level use cases defined for distributed wind will encompass wind turbines in:
- Isolated grids
- Grid-connected microgrids
- Behind-the-meter deployments
- Front-of-the-meter deployments.
One of the critical concerns of the MIRACL team is that the work completed by the laboratories is relevant to the wider DER industry with a clear focus on expanding the incorporation of wind power into the DER sector. To help facilitate this effort, an industry advisory board is regularly updated on MIRACL research plans and products. The advisory board is composed of roughly 10 experts representing organizations such as wind turbine manufacturers, inverter manufacturers DER implementors, DER technology developers, storage manufacturers, universities, state governments, NGOs, and electric utilities.
Rethinking how distributed wind will work within and in support of the larger energy systems including grid- interconnected, microgrids, and isolated systems through advancements in:
- Turbine availability through fault-tolerant controllers
- Grid services from advanced controls in high-contribution systems
- Wind hybrids, alternating current and direct current coupled wind with solar photovoltaic (PV) and/or energy storage.
The MIRACL project is taking a multi-staged approach to demonstrate the additional benefits of distributed wind beyond an alternative source of energy (kilowatt-hour). This approach is outlined below and is ultimately reliant upon industry demonstration and deployment to ensure acceptance and wide dissemination of results developed under MIRACL.
Document past research completed by other forms of DERs and bulk wind to establish a baseline for R&D.
In computer simulated environments, the laboratory teams will demonstrate advancements across the three main research areas (advanced controls, valuation and modeling, and cyber security and resilience).
Lab-Based Physical Hardware-in-the-Loop
The laboratory teams will work with industry partners to support research and demonstrate innovative methodologies, technologies and products in controlled laboratory environments. This takes advantage of DOE physical hardware-in-the-loop infrastructure to increase confidence of the industry and support acceptance of new concepts by consumers, regulators, and system owners.
Industry-Partner Validation and Demonstration
DOE and the national laboratories will support industry deployment of methodologies and technologies, building on ongoing MIRACL research, in real-world environments. This will increase the number of readily available case studies of distributed wind benefits and valuation while allowing companies to further expand product offerings, ultimately leading to increased deployment of distributed wind.
Fault-Tolerant Turbine Controllers
Historically wind turbine controllers have been designed to protect the turbine, this has caused problems within high wind contrition isolated power systems in Alaska, and could cause concern in microgrids and other distribution deployments. To support an advancement in this space, NREL has developed an advanced fault tolerant wind turbine controller which communicates with the microgrid system controller to reduce the need for spinning reserve or other energy storage technologies. This will enable for increased benefits from wind turbines, while also reducing the need for supporting generation operating in standby for the small likelihood of a wind turbine failure. The controller will be tested in a Simulink microgrid model, and run through a variety of fault design cases.
Grid Services from Distributed Wind Turbines
Wind turbines have the potential to provide a variety of services to a local grid beyond just generating real power. But, many of the capabilities of wind turbines are not fully utilized or haven't been demonstrated and well documented. Distributed wind can help maintain grid stability by providing services such as voltage regulation, frequency regulation, and even spinning reserve. In the larger DER context where much of the research has focused around solar technologies, the unique mechanical inertia available in wind technologies has generally not been considered. For wind turbines to provide these services in an optimal and expanded way, development and demonstration of control methods and communication interfaces within a grid and microgrid framework are required.
Some of the earlier researched grid services from bulk-transmission wind that will be focused toward distributed wind applications across the four MIRACL use cases are:
- Active power control and reactive power control
- Inertial response
- Primary frequency response (governor droop)
- Secondary frequency response (automatic generation control)
- Voltage support
- Wind supporting blackstart
- Microgrids with high contributions of distributed wind transitions to and from island or grid-tied operating mode.
Efforts will also be undertaken to understand and quantify the potential economic value, energy resilience, and potential cyber security risks of implementing such advanced power control capabilities. The final result of this work will be a much better understanding of how distributed wind turbines can be used in grid and off grid applications to not only operate through grid disturbances but also to actively improve grid performance while reducing costs for services such as voltage support, spinning reserve, and black start.
To fully participate in a microgrid, isolated grid, or distribution grid distributed wind must be able to simply and effectively coordinate with other DERs on the system. Under this research area the team is working to identify the challenges and opportunities of wind hybrids to value and support eased integration of distributed wind turbines with solar PV and energy storage systems. Some of the high-level challenges and opportunities are:
- Wind coupled through alternating current or direct current with energy storage can
buffer the variability in load and wind generation.
- The cost-benefit trade-offs of coupling wind and storage behind a common inverter
will be investigated between this research area and the valuation effort.
- Wind coupled with energy storage can overcome the problem of needing to operate a
diesel above a minimum loading by providing load when needed and then providing power
so the diesel can go off.
- Integration of storage and other DERs in or with the distributed wind turbine and researching the value and effectiveness of integrated dispatchable subsystems that allow a re-definition of the grid using high-variable renewable, distributed power.
Under parallel Hybrid Energy Systems Research the benefits and opportunities for wind and solar PV co-located deployments are being investigated and quantified at a national-scale. Under the MIRACL project, the team plans to further evaluate the relationship between wind and solar and identify areas of improvement for grid integration and control between these two complementary technologies. Through partnerships with other MIRACL team members, the value and opportunities for distributed wind and solar deployments will be better quantified, and the advanced controls required to effectively connect and operate these deployments will be demonstrated.