GridSight® DLR · Dynamic Line Rating.
Answers.
What is GridSight® Dynamic Line Rating (DLR)?
Every overhead line has a maximum safe current - its ampacity - set by a thermal balance: the conductor heats from current and solar radiation, and cools through wind and radiation. GridSight® DLR solves this balance in real time for every span using live weather data, revealing the line's true capacity at each moment instead of a fixed worst-case assumption.
What is the problem with static line ratings?
Static ratings assume the worst plausible combination of conditions - maximum temperature, minimum wind, maximum solar radiation - happening all at once. In practice those conditions rarely coincide, and real atmospheric cooling is almost always greater than assumed. The result is systematic underutilisation: lines that could safely carry more current are held back artificially.
How does GridSight® DLR help reduce congestion and prevent overloads?
By determining dynamic capacity in real time, GridSight® DLR lets operators seize extra transport capacity when conditions allow, and warns when true capacity is lower than assumed. This reduces congestion, avoids unnecessary curtailment and redispatch costs, and prevents overloads - keeping power delivery consistent and safe.
What rating modes does GridSight® DLR support?
Three modes, sharing one computational framework: AAR (Ambient Adjusted Rating), which adjusts for real air temperature; DLR, fully dynamic using real-time wind, temperature and solar radiation; and TATL (Temporary Admissible Transmission Loading), which evaluates maximum admissible current over a configurable horizon using conductor thermal inertia and live current data.
What methodology and standards do you use for line ratings?
GridSight® DLR solves the conductor thermal energy balance per span, in compliance with CIGRE TB 601 and IEEE Std 738-2023. Each cycle acquires and validates input data, interpolates it along spans, computes the thermal balance per span, and aggregates results to identify the critical span - the most thermally restrictive point on the route.
Can GridSight® forecast capacity ahead of time?
Yes. GridSight® provides forecast DLR with a 7-day horizon and a confidence band on every forecast - essential for day-ahead markets, outage planning, and maintenance scheduling.
What outputs do operators see from the GridSight® DLR module?
Operators get a Power Profile dashboard (dynamic ampacity with confidence band, static baseline, injected current, and KPIs like minimum/average DLR and overload time), critical span statistics, conductor temperature profiles (surface, average, and core, per phase), clearance profiles verifying sag compliance, geospatial alert maps, an SLR configuration panel for static-vs-dynamic comparison, and a TATL dashboard for emergency overload assessment.
What inputs does the GridSight® DLR module need?
Three input groups: meteorological data (air temperature, wind speed and direction, solar radiation, precipitation), line geometry (tower latitude, longitude, altitude, cable azimuth, ground albedo), and conductor data (diameter, DC resistance, temperature coefficient, emissivity, absorptivity, maximum surface temperature, bundle configuration, and conductor mass). Optional real-time conductor surface temperature and substation voltage/current measurements unlock the TATL transient overload mode.