Weather-based and conductor state measurement methods applied for dynamic line rating forecasting

Well-known effect of dependency of the overhead line temperature from weather conditions, especially wind speed and temperature has been applied both for line capacity assessment and for line capacity forecast. The main difficulty is to build the theoretical line temperature model that reflects all physical phenomena and covers wide range of different overhead line (OHL) types, with different mechanical and electrical line structures. It can be overcome by building weather-based model using conductor state measurements. The paper describes the model influencing factors which are possible to estimate on the basis of the real measurement in the field. Described solution was deployed in Distribution System Operator (DSO) Energa in Gdansk, Poland where both weather- based and conductor state measurement methods have been deployed. In the first stage, the conductor state (temperature) method was used for the calibration and tuning the model of line thermal behaviour. After some period of exploitation and obtaining satisfactory results and accordance of the results based on both methods, the weather based method has been applied to the similar types of the overhead lines.