Abstract:
Lightning is not only a serious weather hazard but also it has fascinated and excited humans
for as long as they have watched the skies. It has been estimated that the earth is struck
by 100 lightning bolts every second. Now a days lightning hazard is an important issue
of major interest for the engineers and architects while designing the electric equipment &
tall structures. Analyses of lightning surge characteristics deserve much more importance
for designing protection scheme for communication tower against lightning. If a return
stroke hit upon any metallic structure such as communication tower suited on multi-storied
building’s roof, the lightning transient over voltage will propagate through the columns,
beams and other metallic structures of the building. If proper protection is not provided
against lightning, the building, electric equipment and also human being living inside the
building will be affected. Obviously this matter has been deserving much more attention for
public safety. Modern power and communication system includes many electronic appliances
for controlling and information processing purpose. It is essential to operate communication
systems utilizing these electronic appliances. In this research the lightning surge response
e.g, nature of voltage, current, surge impedance, electric field distribution and effect of direct
stroke in another word the lightning surge characteristics on the multi-storied building and
communication tower have been analysed. Induced effect of direct stroke on electronic
equipment inside the building on different floors has also been analysed. Two different
methods are used to analyzed the surge characteristics. Firstly Numerical Electromagnetic
Code (NEC-2) is used as simulation tool for finding the surge response. Secondly ATP Draw
(Alternative Transient Program) has been used for finding the surge characteristics. In this
research IEEE model, Pinceti model and Fernandes-Diaz model of MOV type surge arrester
are simulated with ATP-EMTP modified their parameters to determine the optimum values
for designing proper protection scheme for the typical mobile phone towers.