Comparative analysis of overhead power transmission lines based on loadability characteristics

The loadability curves of different types of overhead transmission lines are computed and compared in this paper, for line length up to 500 km. The considered solutions are: traditional three-phase single and double circuit ac lines, four-phase ac lines, monopolar and bipolar HVDC lines and combined ac-dc lines. The loadability curves are computed accounting for thermal limits, voltage drop, power losses, steady-state and transient stability.