We’re evaluating dynamic line rating on a 115 kV tie to defer a 2027 reconductor, but weather-driven variance during the 18:00–21:00 ramp seems to eat into N-1–1 headroom faster than our contingency analysis can adapt… For those operating DLR in real time, what probability-of-exceedance (P90/P95) threshold and curtailment trigger have preserved TTC and TPL-001 margins without creating control room churn?
We run P95 in the 18:00–21:00 window with a 10‑min rolling look‑ahead and cap credited uplift to +15% over static; curtail if the look‑ahead projects TTC erosion >3% or the P50–P95 spread >15 MW for two scans. Outside the ramp we’ll allow P90 when wind is steady, but we still “freeze” the rating 5–10 min after the first N‑1 so N‑1‑1 margin isn’t whipsawed.
@harris66 We’ve kept TTC/TPL-001 margins steadier by running P90 during the 18:00–21:00 ramp with a +12% DLR cap and a hard 3°C conductor‑temp guardrail; we trigger curtailment when the temp forecast hits that guardrail (not on TTC erosion), and if gust factor jumps (>1.4) we flip to P97 until it settles…