Innovators are working to develop the next generation of technology to address what’s known as a "black start": restoring power without the support of the external grid. The CleanStart-DERMS project involves building a restoration solution which leverages 100% of distributed energy resources (DER). The CleanStart-DERMS is focused on integration of the distributed energy resource management system (DERMS) with a key utility partner, the U.S.-based City of Riverside Public Utilities.
The project team aims to design, implement, and demonstrate a novel method for fast customer restoration of power during a system outage. In addition, the team will provide the capability to black start utility services from a high penetration of DER (such as solar and wind) distribution feeders. This demonstration, which will show the efficacy of a new DER-driven resilience concept, is multifaceted. It will include validation and implementation of real-time analytics used to evaluate the stability of each line segment and reconnected generation clusters. Device and DER cluster control layers can additionally be optimized for the black start application when required.
The CleanStart-DERMS project is organized in such a manner that it can implement a repeatable design process. Specifically, it uses a transmission, distribution, and communication simulation that is agnostic to the generation source. In addition, the project will use high-fidelity sensing and predictive analytics, modular DER control, and a dynamic microgrid configuration that can be optimized in real time. The real-time optimization will provide support to the bulk power system during restoration, primarily from small distributed generators including solar photovoltaic (PV), while simultaneously considering critical load constraints.
The control and real-time analytics framework integrates data from high-fidelity sensors including distribution synchrophasors and point on wave line current measurement, all capturing voltage and current data in a below seconds timeframe. These capabilities enable users to evaluate the ongoing risk of an outage to the feeder, allowing proactive segmentation and the stability of each node during the Cleanstart-DERMS restoration process. The control strategy is leaves-to-root, or customer to bulk system — a fundamentally opposite approach to normal power restoration where the bulk system is the first consideration.
The analytics, enabled by applying reinforcement learning to advanced sensors, will determine the best available controllable device configuration before the outage. The resources from that configuration — in conjunction with inverter-based black start devices — will be used to create a robust, islanded network. In turn, the islanded network can then be optimized to black start the remaining feeder and non-controllable DER devices.
The self-healing microgrid and distribution grid configuration will be robust to both cyber and physical events, with application of a secure supervisory control and data acquisition (SCADA) protocol wrapper to the DERMS platform. It will also provide critical restoration support to the primary substation from renewables, other small distributed resources, loads, and buildings. The CleanStart-DERMS methodology can enable parallel restoration to take place, accounting for uncertainty in topology and resource availability.
The outcome flowing out of the CleanStart-DERMS project is expected to be of interest to a wide range of actors. For instance, CleanStart-DERMS intends to publish a strategy — for resilience-based microgrids, DER-driven black start, and segmented restoration — which can be adapted anywhere. This approach by the CleanStart-DERMS project integrates several streams: new technologies, system control theories, and advanced analytics. The project will demonstrate their application through field validation.
Some analysts think that the CleanStart-DERMS could become the one project which uniquely demonstrates the capability of starting a feeder from a complete outage. That means it can encompass the "entire tree": it goes "from the leaves" (for example, the DER and the customers) "to the root" (for example, the feeder head). It means resynchronizing with the wider area network using just a minimal amount of conventional electricity generation. The CleanStart-DERMS aims to achieve this through integrating and validating all of the key elements with enhanced communication and control for agile islanding: the distributed analytics, the controls, and the DERMS.