Protection of three-phase electric motors

U ovome radu je bilo potrebno opisati koncept zaštite trofaznih elektromotora. Definirani su osnovni problemi te osnovna podjela metoda koje se koriste za vršenje takvih zaštita. Opisane su opće jednadžbe, prikazane osnovne karakteristike releja i principi zaštita od međufaznih kvarova, zemljospoja, preopterećenja, obrnutog redoslijeda faza. Isto tako opisani su moderni numerički releji tipa MCBs i RTX³.In this paper, it was necessary to describe the concept of protection of three-phase electric motors. The basic problems and the basic division of the methods used to perform such protections are defined. The general equations are described, the basic characteristics of relays and the principles of protection against phase-to-phase faults, earth faults, overloads, reverse phase sequence are shown. Modern numerical relays of the type MCBs and RTX³ are also described