Applications of Electrically Assisted Manufacturing - Electrically Assisted Forming - page 299

structures because they require less right-of-way restrictions. When setting up a new
transmission line system, there are several main procedures that need to be followed
(e.g., installing the foundations, erecting the towers, pulling the conductors), which
is further explained in [ 27 ]. The installation of the conductors is an important step in
the transmission structure finalization. After a regulated amount of time has passed
since setting the footings for the transmission towers, one can then begin to pull the
conductor lines. In most cases, the wires are mounted to vehicles and pulled through
the stringing hardware to position the lines and set the sag in the lines.
11.5.3 Commercial Conductors and Sizing
There are several types of conductors that can be used as transmission lines; how-
ever, the most-common is the steel-reinforced aluminum conductor (ACSR). This
conductor has a relative low-cost and high weight-to-strength ratio compared to its
competitor conductors. Several other conductor types are an all aluminum conduc-
tor (AAC) and an all aluminum alloy conductor (AAAC) [ 28 ]. The different con-
ductor types are named after different objects. Specifically, the AAAC conductors
are named after types of trees, while the ACSR conductors are named after differ-
ent animals (the ACSR conductor used in the example in the following subsec-
tions is named “DOG”). According to Castro [ 29 ], the ACSR-type conductor can
be sized two different ways. First, the most economical method is to use Kelvins
Law, which states, “The most economical area of a conductor is that for which the
annual cost of energy losses is equal to the interest on that portion of the capital
outlay which may be considered as proportional to the weight of the conductor.”
Second is the more efficient sizing method, in which the conductor is sized based
on balancing the I 2 R losses and the installation cost. Figure 11.49 shows how the
most efficient conductor is sized. To put the cost of an OHTL into perspective,
Fig. 11.49 Determination of
the most efficient conductor
size [ 29 ]. The most efficient
method of sizing a conductor
is to balance the power losses
and the installation costs,
since these are inversely
proportional