In this paper we describe a new Benders decomposition approach to solve pow
er transmission network expansion planning problems, This new approach is c
haracterized by using a linear (0-1) disjuntictive model which ensures the
optimality of the solution found and by using additional constraints, itera
tively evaluated, besides the traditional Benders cuts. The results obtaine
d, considering a real world power transmission network expansion planning s
tudy with the southeastern Brazilian system, show the efficiency of this ap
proach.