Indirect weather‐based approaches for increasing power transfer capabilities of electrical transmission networks

Abstract

Dynamic line rating (DLR) systems are recognized as a cost‐effective and socially accepted asset for relieving network congestion and uprating existing transmission systems, based upon accessing additional weather‐dependent capacity of overhead lines. Although direct and indirect DLR methods are available, utilization of indirect weather‐based approaches, that is, sensors are not installed on the conductor, are of increasing interest due to fast installation times, that is, no requirement for line outages and lower capital costs, with achievable potential for wide‐area implementation. An extensive review is presented on the components and requirements of such systems, including weather stations, forecasting models, downscaling and DLR calculations, overhead line and conductor thermal models, and communication platforms. In addition, the features of practical instances of these systems are briefly reviewed. Moreover, a systematic approach is introduced for statistical evaluation of the high‐level DLR potential across an entire region, as well as an assessment of the line‐level DLR ampacities within an electrical grid, based on (weather forecasting) reanalysis data. The proposed methodology can disclose available additional capacity as part of early‐stage planning for wide‐area DLR systems. The island of Ireland and the 110 kV network of the Republic of Ireland (ROI) power system are considered as the study cases, with comparison made against seasonal static ratings and ambient temperature adjusted line rating methods.