January 20, 2025
Article

New Tool Streamlines Generator Performance Evaluations

PNNL and BPA Deliver a Data-Driven Solution for Grid Reliability 

Transmission line against grey blue sky

By streamlining the power plant evaluation process, the Generator Scorecard enhances the overall efficiency and reliability of the power grid. 

(Photo by Rose Galloway Green | Unsplash)

The Department of Energy (DOE) recently rolled out the Generator Scorecard, a tool developed by Pacific Northwest National Laboratory (PNNL) in collaboration with the Bonneville Power Administration (BPA). Designed to automate generator performance evaluations, this tool tackles one of the power grid’s biggest challenges: maintaining stability across extensive transmission systems like those managed by BPA.

BPA operates one of the largest and most complex transmission networks in the United States, delivering hydropower from the Columbia River to millions of customers across the Pacific Northwest. Managing this vast network requires precise control of frequency and voltage to maintain stability, especially in a region that relies on a dynamic mix of renewable and traditional energy sources. When generators trip offline, others must respond quickly and effectively to prevent disruptions. Until now, the process to review the performance of generators during these situations relied on manually setting up comparisons between simulations and measurements. 

“BPA needed a reliable way to ensure their generators respond correctly when others trip offline, and the Generator Scorecard was built specifically to address that challenge,” said Jim Follum, an electrical engineer and PNNL. “Automating these evaluations helps reduce the workload on engineers while pinpointing generators that need attention, ensuring potential issues are resolved before they escalate.” 

The Generator Scorecard automates the evaluation of frequency and voltage control. Maintaining the grid frequency near 60 Hz and ensuring stable voltage levels are critical to system reliability. The tool uses data from phasor measurement units (PMUs), which provide time-synchronized measurements of the grid’s frequency and voltage. These measurements, reported 60 times per second, were used to detect sudden changes in the power grid and analyze the response of generators. 

“This project came out of detailed conversations with BPA about their operational needs,” Follum said. “BPA’s insights into transmission operations and their feedback helped guide the development of the Generator Scorecard, ensuring its integration into their workflow to support grid reliability.” 

Screenshot of the Generator Scorecard
Screenshot of the Generator Scorecard's user interface displaying a summary of a power plant's performance over a one-month period.

Strong partnerships inspire innovation

PNNL and BPA have a longstanding history of collaboration, jointly developing methodologies and tools to enhance power grid operations. BPA’s operational insights combined with PNNL’s technical expertise led to the development of the Generator Scorecard that addresses immediate needs while paving the way for future advancements in grid management. 

PNNL’s ability to quickly develop a prototype of the Generator Scorecard stemmed from an earlier partnership with BPA to develop Archive Walker, a MATLAB-based tool designed to analyze archived PMU data. Archive Walker demonstrated how large data sets could be summarized into actionable insights, providing a strong foundation for the Generator Scorecard. 

“Leveraging prior tools like Archive Walker enabled us to develop a prototype for the Generator Scorecard efficiently,” Follum said. “We created a tool capable of analyzing PMU data in real-time and performed a one-month demonstration in just nine months. Developing the Generator Scorecard from scratch would have likely taken up to two years.” 

Following its successful field demonstration, the next step is to partner with a software vendor to prepare the Generator Scorecard for commercial deployment. This effort will ensure the tool is robust, user-friendly, and compatible with various utility systems worldwide. Additionally, PNNL is engaging with other utilities to gather input and validate the tool across different environments, tailoring it to meet the diverse needs of the energy sector. 

For more information about the Generator Scorecard, visit the Office of Electricity’s blog

Published: January 20, 2025

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