Faults producing load disconnections or emergency situations have to b
e located as soon as possible to start the electric network reconfigur
ation, restoring normal energy supply. This paper proposes the use of
artificial neural networks (ANNs), of the associative memory type, to
solve the fault location problem. The main idea is to store measuremen
t sets representing the normal behavior of the protection system, cons
idering the basic substation topology only, into associative memories.
Afterwards, these memories are employed on-line for fault location us
ing the protection system equipment status. The associative memories w
ork correctly even in case of malfunction of the protection system and
different pre-fault configurations. Although the ANNs are trained wit
h single contingencies only, their generalization capability allows a
good performance for multiple contingencies. The resultant fault locat
ion system is in operation at the 500 kV gas-insulated substation of t
he Itaipu system.