Evolution of the design for the 275 kV transmission system of NEB

The Malaysian National Electricity Board's (NEB) 275 kV transmission system has developed over the last 20 years from a simple spur arrangement into an integrated National Grid system. The National Grid is still expanding. Plan is underway to integrate the system with those of the neighboring countries. Over the years several modifications, some of which are considered innovative, were made in the design of the system. Perhaps NEB is among the first utilities in the world to introduce wooden crossarms with differential insulation for transmission line at 275 kV level. Those modifications are described in this report. Special emphasis is placed on those changes that affect the lightning performance of the system.