B. Ramamurthy, D. Sblendorio
Critical Loop, Inc.,
United States
Keywords: BESS, safety, reliability, autonomous, fault detection, remote operations
Summary:
There are acknowledged benefits to deploying battery energy storage systems (BESS) to alleviate grid constraints in dense urban and industrial settings. Utilities and the US Department of Defense have expressed interest in developing rapidly deployable BESS in a flexible and relocatable format. Achieving high levels of safety and reliability are a pre-requisite to being able to deploy a network of Distributed Energy Resource (DER) assets in this format to serve critical infrastructure or temporary grid backup needs. We describe results from real-world field deployment supporting customer emergency backup needs, conducted by Critical Loop, Inc. in Southern California in 2024. These deployments implemented software developed to enhance the safety and reliability of BESS through fault detection, isolation, and recovery (FDIR). A state-of-the-art remote control center was implemented by developing software that was used to remotely manage BESS in multiple configurations- single or multiple BESS at the same location, BESS tied with generation, and BESS in transit between locations. The BESS were monitored through a centralized control center using real-time telemetry and data analytics. Real-time response to issues was generally possible. Telemetry was logged and data retained for trend analysis and long-term evaluation of hardware and software reliability improvements. The system was designed to allow for easy remote adjustment of set points and thresholds used to control the system, with configurable automated sequences to manage charging and discharging cycles of the BESS. The control algorithms account for any changes in load or inverter state, compensating and adjusting thresholds to account for any abrupt changes in remaining capacity due to inverter faults. Simultaneously, the software remediated faults, managed to within the acceptable operating limits of the hardware. As a result, individual inverters can be brought offline for maintenance and the algorithm will compensate and continue to function at reduced capacity. Minimal footprint edge compute devices were installed to convert legacy industrial protocols to a modern request/response interaction. Each edge compute device interfaces with a single BESS, converting legacy industrial protocols, to create an endpoint that persists the state of the DER through telemetry channels. Each endpoint is discoverable, and has the ability to maintain identifying information to inform the greater network on how to interact with it. Any of the underlying legacy data that is available on the DER can be transformed into a queryable, and if supported, commandable channel. The software can autonomously detect anomalies and promptly trigger customized, pre-configured alerts. All relevant telemetry parameters to monitor the state and health of BESS units and the circuit were pulled remotely. The alert system was configured to report through a customer-facing dashboard or through email, text or Slack message alerts. In the event that physical inspection was required, the use of remote work tools like FaceTime allowed trained site personnel to be “boots on the ground” under the supervision of Critical Loop’s engineering team to perform permissible, safe actions that restore operations (such as resetting breakers or telemetry devices).