Method of electrical protection of a synchronous machine and electric power generation plant for powering an electric network

The present invention relates to a method of electrical protection of a synchronous machine, for example a generator, and an electric power generation plant for powering an electric network comprising an electrical protection for synchronising a synchronous machine to an electric network. The method of protection according to the invention establishes a period in which the electrical protection is active and also the instant in which said protection ceases to be active to offer the necessary protection and at the same time not prevent the correct synchronisation.