Summary
Read more on ELECTRATransmission system operators (TSOs) need accurate, near-term knowledge of line ratings to prevent conductor overheating and excessive sag, which can compromise safety and equipment lifespan. This brochure focuses on forecasting Dynamic Line Ratings (DLR), predicting overhead line thermal capacity on timescales ranging from minutes to days. Due to the strong influence of wind convection in complex line corridor environments, DLR forecasting is a technically challenging process.
Table of content
1. Introduction and Background
1.1. Heat Balance for Thermal Rating Calculations
1.2. Conductor Temperature Limitations
1.3. Weather Conditions for Line Ratings
2. Static Line Rating (SLR) Overview
2.1. Seasonal Static Ratings
2.2. Limited-Time Static Ratings
3. Line Corridor Weather Conditions
3.1. Weather Parameters
3.2. Chronological Weather Patterns in Line Corridors
3.3. Longitudinal Weather Variations in Line Corridors
4. Dynamic Line Rating (DLR) Methods
4.1. Long Time Emergency (LTE) Dynamic Line Ratings
4.2. Short-Time Emergency (STE) Dynamic Line Ratings
4.3. Ambient-Adjusted Line Ratings (DLR-AA)
4.4. Real Time Monitoring Dynamic Line Ratings (DLR-RTM)
4.5. Monitoring Considerations
5. Dynamic Line Rating Forecasting Methods
5.1. DLR-AA Vs DLR-RTM Forecasting
5.2. Meteorological Forecasting
5.3. Probabilistic Forecast Models
5.4. DLR “Very-Short Term” Forecast (1hr-6hr)
5.5. DLR “Day-Ahead” Forecast (24hr-48hr)
5.6. Extension to Ensemble Forecasting
5.7. Other Forecasting Approaches
5.8. Forecasting Accuracy
6. Line Thermal Rating Risks
6.1. Line Rating Uncertainties
6.2. Line Design and Rating Errors
6.3. TCMAX Exceedance Risk
6.4. Line Versus Span Risk
6.5. Sensitivity of DLR to TCMAX and Static Weather Conditions
7. Use of Dynamic Line Rating in System Operations
7.1. Overview - Managing Power Flows on Network Elements
7.2. Power Flow Consideration in the Application of DLR
7.3. Economic Aspects of Operating with DLR
8. Application Examples
8.1. PJM (US) – DLR-AA Method
8.2. Hydro One (Canada) - DLR-AA Method
8.3. ELIA (Belgium) A – DLR-RTM Method
8.4. RTE (France) – DLR-RTM Method
8.5. ELIA (Belgium) B – DLR-RTM Method
8.6. Brazil - Predictive Ratings
8.7. ERCOT (US) – Line Rating - Real Time Air Temperature Adjusted
8.8. Idaho Power (US) – DLR Forecasting
8.9. Elektro Ljubljana - ELj (Slovenia) – DLR-RTM Method
9. Conclusions
Appendix A
A.1. General Terms
A.2. Specific Terms
Additional informations
| Publication type | Technical Brochures |
|---|---|
| Reference | 969 |
| Publication year | |
| Publisher | CIGRE |
| ISBN | 978-2-85873-674-4 |
| Study committees | |
| Working groups | WG B2.59 |
| File size | 9 MB |
| Pages number | 95 |
| Price for non member | 180 € |
| Price for member | Free |
Authors
Convenors
D. DOUGLASS, 2014-2020 (US), G. WATT, 2020-2024 (CA)
Secretary
G. BIEDENBACH (DE)
I. ALBIZU (ES), K. BAKIC (SI), W. CHISHOLM (CA), G. DIANA (IT), M. FONTAINE (FR), J. GENTLE (US), B. GODARD (BE), J. IGLESIAS (ES), J. JARDINI (BR), R. KUWAHATA (BE), A. MICHIORRI (FR), B. NEMETH (HU), H. M. NGUYEN (BE), R. STEPHEN (ZA)
Keywords
Overhead line ratings, Effective perpendicular wind speed, Dynamic line rating (DLR), DLR -LTE, DLR-STE, DLR-AA, DLR-RTM, DLR forecasting methods, Line rating risks, DLR applications
