Project Highlight
Transient-Based Line Protection Drives Midwest Grid Modernization
Challenge
ITC Midwest needed a reliable solution to enhance transmission line protection, especially for lines connected to inverter-based resources (IBRs).Fault current contributions and characteristics from IBRs introduce challenges to conventional phasor-based line protection algorithms. Transient-based line protection overcomes these problems and provides secure and dependable protection.Previously, ITC Midwest successfully used the traveling-wave fault-locating methods in the SEL-T400L to identify problematic insulators and mitigate multiple temporary faults. Building on this successful field experience, the transmission company sought an advanced solution for challenges associated with fault current contributions from IBRs.Solution
The SEL-T401L is an ultra-high-speed line protective relay, which includes transient-based protection functions that are not hindered by the IBRs. This functionality makes the SEL-T401L an effective and ideal choice for transmission lines connected to IBRs.Through continuous collaboration with SEL and participation in several educational opportunities, ITC Midwest gained deeper insights into the benefits and applications of the SEL-T401L for both traditional and IBR systems.Results
IITC Midwest exchanged its SEL-T400L relays for SEL-T401L relays. The majority of its 45 SEL-T401L relays are now protecting lines connected to IBRs.ITC Midwest chose to standardize on the SEL-T401L and the SEL-411L Advanced Line Differential Protection, Automation, and Control System on IBR-associated lines, providing comprehensive and redundant transmission line protection.Customer ProfileCustomer: ITC MidwestLocation: Iowa, USAIndustry: Electric Power TransmissionApplication: Transmission Line Protection