Overhead lines Dynamic Line rating based on probabilistic day-ahead forecasting and risk assessment

Abstract

Dynamic Line Rating is a technology devised to modify an overhead line's current-carrying capacity based on weather observation. The benefits of this modification may include reduced congestion costs, an increased renewable energy penetration rate, and improved network reliability. DLR is already well developed, but few papers in the literature investigate DLR day-ahead forecasting. The latter is central to DLR development since many of the decisions related to grid management are taken at least on a day-ahead basis. In this paper, two problems related to DLR forecasts are dealt with: how to achieve precise, reliable calculations of day-ahead forecasts of overhead line ampacity and how to define a methodology to calculate safe rating values using these forecasts. On the first point, four machine-learning algorithms were evaluated, identifying the best approach for this problem and quantifying the potential performance. On the second point, the developed methodology was tested and compared to the current static line rating approach.

A Diagnostics Framework for Underground Power Cables Lifetime Estimation Under Uncertainty

“…The cable temperature estimation is a widely addressed research area with applications in dynamic line rating [21], [22], [23] and lifetime estimation [24]. In addition to the thermal stress, there are models focused on the analysis of the joint influence of electrical and thermal stresses [17].…”

An Equivalent Heat Transfer Model Instead of Wind Speed Measuring for Dynamic Thermal Rating of Transmission Lines

“…Under the conditions of the same ambient temperature and Al ball temperature, the forced convection heat transfer coefficients h f with different wind speeds and the natural convection heat transfer coefficient h 0 are firstly calculated according to (13), (14) and (17). Meanwhile, a variable err c is introduced to compare the difference between h 0 and h f , which is calculated by (19).…”

“…According to the differences of monitoring data, the models of the DTR technology can be divided into two categories. The first type of DTR model, called the Weather model, calculates the conductor ampacity by directly monitoring all the weather data, including the ambient temperature, wind speed, wind direction and global solar irradiance [13,14]. A lot of sensors are needed to measure the weather data in Weather model [15].…”

Analysis of the Climatic Factors Influence on the Overhead Transmission Lines Reliability

“…An analysis of the risk-based approach methodology in assessing of the OTL stability [21] as a probabilistic characteristic that determines normal power supply to consumers and similar researches [22]- [25] in the field of power grid reliability showed that traditional reliability targets such as SAIFI, SAIDI, EENS [26], LOLE, LOLH [27], [28] do not allow to fully evaluate and analyse the failure rate of power outages associated with climatic factors. These indices characterize the failure rate, the outage time without indicating the reason of accidents.…”