Exceeding the electric field’s limit value is not allowed in the vicinity of high-voltage power lines because of both legal and safety aspects. The design parameters of the line must be chosen so that such cases do not occur. However, analysis of several operating power lines in Europe found that the electric field strength in many cases exceeds the legally prescribed limit for the general public. To illustrate this issue and its importance, field measurement and finite element simulation results of the low-frequency electric field are presented for an active 400 kV power line. The purpose of this paper is to offer a new, economical expert system based on dynamic line rating (DLR) that utilizes the potential of real-time power line monitoring methods. The article describes the expert system’s strengths and benefits from both technical and financial points of view, highlighting DLR’s potential for application. With our proposed expert system, it is possible to increase a power line’s safety and security by ensuring that the electric field does not exceed its limit value. In this way, the authors demonstrate that DLR has other potential applications in addition to its capacity-increasing effect in the high voltage grid.

This paper aims to demonstrate the performance and reliability analysis of a dynamic line rating (DLR) system at the Bulgarian demonstration site of the FLEXITRANSTORE project. As part of the project, various manufacturers’ different line monitoring DLR sensors and weather stations were installed on a 110 kV double-circuit overhead line (OHL). These devices provided input parameters to the DLR system based on objective measurements. This paper used statistical tools to examine the reliability and accuracy of installed devices, thus making products from different manufacturers comparable. In addition, two independent line monitoring and DLR models have been developed: the black-box and extended white-box models. The performances of the two models were analyzed for the same input parameters and compared to the field measurements. Based on the presented results, the reliability and accuracy of the applied weather stations of different companies were almost the same. This conclusion cannot be said for DLR line monitoring sensors, where the devices could be differentiated based on reliability and measurement accuracy results. In terms of models, the usability of the extended white-box model seemed to be limited in certain weather conditions, implicating a more significant role for soft-computing-based DLR models in the future. In addition to the results, root causes for the errors and future directions that may provide a framework for further research are also presented.

Dynamic line rating method (DLR) is a novel and cost-effective way to extend power overhead lines (OHLs) transfer capacity based on real-time monitoring of the weather parameters in the vicinity of the conductor. Via DLR models not only real-time, but also day-ahead transfer capacity calculation is possible which is more important from the aspect of TSOs. It is important to mention, that these DLR predictions are based on weather forecasts that usually has some uncertainty. The aim of the paper is to identify the potential risk of forecasted power line ampacity due to uncertain weather forecast. To investigate this rarely studied topic, several simulations were carried out applying real power line parameters and forecasted weather data. The results of the simulations showed that under unfavorable weather conditions the uncertainty of the weather prediction could significantly increase the sag of the OHLs if they fully utilized. To monitor the real-time state of the conductor’s sag, a novel risk factor calculation method was also investigated that provides additional safety information for the system operators in real time.