Performance Comparison of Using ACSR and HTLS Conductors for Current Uprating of 230-kV Overhead Transmission Lines

This work involves performance evaluation of current uprating of overhead transmission lines by using Aluminum Conductor Steel Reinforced (ACSR) and High Temperature Low Sag (HTLS) conductors. The test cases are 230-kV, double-circuit, single-bundle and twin-bundle, overhead transmission lines. The existing conductors are 1272 MCM ACSR, while the candidate conductors are five types of HTLS with comparable sizes. The performance comparison is carried out under a twofold ampacity condition. It can be concluded from numerical simulations that HTLS conductors are attractive for replacing ACSR conductors in current uprating. By using HTLS conductors, more clearance to ground is gained and it is feasible to reduce right of way. However, it is mentioned that the line loadability of HTLS conductors is slightly less than that of ACSR conductors so that steady-state stability limit is of concern.