Transmission Line Overloading Analysis Using Probabilistic Dynamic Line Rating

Load growth and addition of renewable energy generation occur in a way that makes the power grid being operated closer to its physical limits. Increasing the flexibility of the electrical power system is an essential step in ensuring a continued high reliability of the electricity supply. Dynamic line rating (DLR) can be utilized to increase the reliability of the system by ordering curtailment only when needed. In this paper, a probabilistic approach is introduced for the operational overload protection based on the probability distribution of the actual line capacity. That distribution is obtained by considering measurement and prediction errors in weather parameters as well as other uncertainties. The results indicate that probabilistic DLR based protection would allow operational decision-making based on a fair balance between dependability and security. This is not possible using the classical overload protection system.