deicing of transmission line

Line compaction is a proven method not only for reducing line width, but also for increasing the transmission capability of the line due to lower surge impedance. In addition, the electric and magnetic field at the edges of the line corridor are reduced to such an extent that they are not expected to have any negative effects on the environment.

As already explained in the chapter on compact lines, line compaction is pri- marily based on the principle of minimizing interphase spacing. As a result of this, and also since the interphase spacings are somewhat smaller than those encoun- tered in the case of normal overhead transmission lines, there is greater risk of interphase flashover with a compact design when two conductors are moved close to one another, for example as a result of wind, ice shedding or short circuit; this may lead to an interruption in service. Interphase spacers (IPS) are used to avoid this.

In the last few years, increased use of interphase spacers of composite design has been made possible due to the generally massive advances made in the development and acceptance of composite insulators. In this application, it has thus been possible to utilize the specific properties of composite technology, such as low weight, high flexibility and excellent hydrophobicity to name just a few.