Accurate to ±100 mm.
On ground clearance, in place of a fixed worst-case assumption.
How a National TSO Found 25% Hidden Capacity on a Fully Energized 400 kV Line.
A hybrid DLR system installed live, turning sensor and weather data into dispatch-ready capacity.
Up to 25%Additional line capacity unlocked.
95 kmDouble-circuit 400 kV transmission corridor length.
15 minRecalculation cycle for live ampacity and alarms.
The challenge.
A live 400 kV interconnector with no real-time view of its own operating margin.
A national transmission system operator in South Asia, and its regional grid control centre, had no way to see how one of their 400 kV double-circuit corridors actually behaved hour to hour. Load on the line already ran close to its theoretical limit, yet operators were managing it against a single, conservative static rating, with no visibility into how conductor temperature, wind and ground clearance were really moving.
There was no way to know how much genuine headroom sat unused. The operator needed that visibility delivered without taking a live, energized asset out of service, and without limiting coverage to a handful of instrumented points.
The brief was clear: full-corridor intelligence, fed directly into the same SCADA/EMS stack operators already used to make dispatch decisions.
The solution.
A hybrid DLR system installed live, turning sensor and weather data into dispatch-ready capacity.
Enline deployed GridSight® DLR across the double-circuit corridor with a specialist sensor hardware partner. Field sensors measuring conductor temperature, line current, wind speed and direction, and LiDAR ground clearance were installed using the hotline method and powered by induction from the line itself. The corridor never came out of service. Weather-model inputs extend visibility beyond the sensor-only points, across the full corridor.
Every reading is encrypted and transmitted over M2M SIM or Iridium satellite links to a cloud engine running an IEEE 738-2012 / CIGRE TB601-compliant heat-balance calculation. Operators see live loading alongside 2-hour and 24-hour forecasts and historical trends, with two-tier alarms for conductor overheating or clearance violations.
If any individual sensor drops offline, automatic reconnection and alerting kick in and the corridor's calculation keeps running uninterrupted. Calculated data reaches the operator's SCADA/EMS directly via REST API, backed by a three-year AMC once the warranty period ends.
Field sensors + weather-model inputs.
Encrypted M2M SIM / Iridium satellite link.
IEEE 738-2012 / CIGRE TB601 heat balance.
Operator SCADA/EMS via
REST API.
The outcome.
Forward-looking, physics-based capacity in place of a single fixed seasonal assumption.
The results on this corridor were clear: dynamic ratings came in up to 25% above the previous static limits. With direct API integration already in place on SCADA/EMS, the operator now folds that margin into everyday dispatch decisions, instead of treating it as a one-off study.
The system recalculates ampacity every 15 minutes and rolls forward an hour-by-hour forecast spanning 168 hours. A static, worst-case rating gives way to a live, physics-based envelope: accurate to ±100 mm on ground clearance and ±1% on line current, with automated two-tier alerting standing in for manual, reactive surveillance.
Accurate to ±1%.
On line current, feeding the live ampacity calculation.
168-hour forecast.
Hour by hour, rolled forward and recalculated every 10 minutes.