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Real-Time Reliability Management Tools

CERTS VAR-Voltage Management Tool

The CERTS VAR-Voltage Management Tool substitutes a visual, bird's-eye view of the overall health of the grid for difficult-to-read tables of voltages at each monitoring point within the electricity system. By mining, analyzing, and presenting operational data in an easy-to-understand visual format, this tool addresses a key problem facing operators today—data overload—and enables them to effectively and reliably maintain safe operating margins.

Screen shot of the VAR-Voltage Management Tool

Figure. Voltages (and voltage reserves) across the entire western interconnection are prevented visually using different colors to indicate high (green), normal (blue), and low (red) voltage conditions. Diagnostic analysis of observed conditions to determine their severity and effectiveness of different options to address them are integrated directly into the displays.

Screen shot illustrating the distances from voltage collapse. Voltage patterns represented as a combination of high and low voltate condidtions. Voltage patterns represented as normal with some areas of high and low voltate condidtions.

This tool gives reliability coordinators and system operators immediate access to information on system voltages over a wide area, and, more importantly, reactive reserve margins at critical grid locations. The tool provides sensitivity calculations, distances from voltage collapse, remedial action options, and geographically oriented visual displays. Had it been available at the time, the VAR-Voltage Management Tool would have been instrumental in alerting operators to dangerously low reactive reserve margins in the summer of 1996 and might have prevented the resulting widespread power outages that crippled the West Coast.

The tool has been installed at both the Folsom and Alhambra California Independent System Operator (CAISO) control centers.


Carlos Martinez
Electric Power Group, LLC
(626) 685-2015