Aeolus

Motivation

The strong expansion of renewable energies, increasing international electricity trading and the ageing grid infrastructure are already pushing electricity transmission grids to their limits. However, the construction of new power lines is cost-intensive and associated with long planning and implementation periods.

The maximum permissible transmission capacity of overhead lines is usually determined on the basis of a worst-case weather scenario. The current carrying capacity is mainly limited by the maximum permissible conductor temperature of around 80 °C. If the temperature rises above this, the current carrying capacity increases. If the temperature rises above this, the sag of the head increases due to thermal expansion, which means that the required safety distance to the ground and to vegetation or buildings may be undercut.

In order to avoid dangerous operating conditions, such as flashovers, this minimum distance must be guaranteed at all times, even under the most unfavorable conditions. In addition, heating conventional conductor cables above 80 °C leads to irreversible material elongation, which is equivalent to structural damage in the long term.

Since the worst-case scenario used as a basis does not exist in most real operating conditions, the overhead line can be utilized to a higher capacity if the current conductor temperature is known.

Project objectives

As a contribution to the effective use and increase of the transport capacity of power lines based on weather-dependent overhead line operation (WAFB), an innovative fiber-optic sensor technology is to be developed that makes use of a new type of detection of the wind parameters (wind speed and wind direction) in the line environment that are decisive for WAFB. This technology does not require any additional sensors and uses the fiber optic cable in the underground cable to optically detect the wind-induced aeolian vibrations of the head. The fiber optic cable itself thus functions as a distributed, continuous and far-reaching sensor in every span of an overhead line.

The topography along the power line is also crucial for the precise determination of the cooling of the conductor. In the project, a drone is being developed that flies autonomously along the power line and records the topography. In order to ensure continuous inspection along a complete section of the line, the drone is to be supplied with power from the extra-high-voltage line.

Implementation

ITIV involvement

ITIV is coordinating the project. Based on the weather data, AI models are trained to calculate the temperature of the heads and make forecasts for the higher utilization of the lines.

ITIV is also developing an inspection drone that charges up at the high-voltage line and records the topography along the power line.