Conductor Temperature Estimation under Uncertain External Conditions Using a Temperature-Dependent Power Flow

Traditionally used methods for large-scale power system analysis do not take weather conditions into account. Pre-set values of line electrical parameters are used in conventional power flow approaches. However, external conditions, such as weather, which can often be uncertain, affect conductor temperature and consequently transmission line electrical parameters, especially resistance. This dependency of line resistance on weather conditions impacts the results of power flow analysis. Therefore, uncertainty in external conditions introduce uncertainty in line electrical parameter values and in power flow results. In order to account for the impact of external conditions on power systems, a conductor temperature-dependent power flow algorithm is presented in this work; the algorithm is capable of providing not only conventional power flow results of bus voltages, line currents, and power flows, but also conductor temperature of each system branch. Affine arithmetic is used with the developed temperature-dependent power flow approach to enable consideration of branch parameter uncertainties due to external conditions.