The Investigation and Modelling of Vertically Installed Inter-Phase Spacers for the Enhancement of Clearance in Overhead Transmission Lines

The necessity of finding an appropriate solution has become more significant, specifically in OHTLs being installed for a long time. One of the most common solutions is increasing the tension in order to lower the sag of the conductor. This technique depends on the capability of conductors as well as towers to carry an additional mechanical load; otherwise, it may lead to failure. Therefore, finding a new solution to increase the distance of the lower-phase conductors from the ground level has become the main concern.

The traditional application of Inter-Phase Spacers (IPSs) is preventing conductors from swing or unintentional collision as they are exposed to natural phenomena such as storms, snow, and frost.

These non-synchronous swings may become more severe in areas with a harsh climate where the separation of ice from conductors might lead to galloping, and in the worst case, to failure of the power system. By contemplating beyond the prevalent use, the IPS can be considered as a novel method in order to enhance the vertical clearance of conductors to the ground level in OHTLs with the vertical configuration of three phases.

The installation of an IPS with a length less than the distance between two phases and in accordance with predetermined intervals in each span and the implementation of an IPS as a tool for enhancing the vertical clearance of conductors in OHTLs is investigated in this paper. The presented method is mostly applicable in installed OHTLs confronting the low clearance issues as a result of changes after construction or some errors during the design procedure, etc. The study of this paper is on a double-circuit OHTLs with vertical phase configuration. The different aspects of the presented method are investigated in detail. In addition, the required recommendations based on the theoretical results of the study will be presented and finally, theoretical results in a case study will be modelled by an international software.