Investigating effects of weather parameter uncertainty on transmission line power handling capabilities using affine arithmetic

This paper presents an approach to deal with uncertainty in weather parameters when determining transmission line power handling capabilities, in terms of both line thermal rating and voltage stability limits. Weather parameters affect conductor temperature, which in return affects line electrical parameters. Wind speed and direction, for example, have a significant cooling effect, which can result in higher allowable currents through the line before reaching the maximum conductor temperature. At the same time, the line electrical parameters, particularly resistance, are a function of temperature and would therefore affect the line electrical model and its maximum power transfer point before voltage collapse. Weather conditions are variable and uncertain; in order to account for the uncertainty in weather parameters, this paper presents an approach based on the affine form of interval arithmetic. The results of the affine arithmetic-based approach are then compared with static line ratings. The approach is tested on a single-line 2-bus system and on a 14-bus transmission network.