A diagnostic system for three-phase asynchronous machines

The authors present a brand-new diagnostic system for three-phase induction machines as well cage and slipring motors which allows one to protect the machine against all faults of practical importance within the active parts. The faults include all kinds of winding damage, rotor eccentricity, and rotor unsymmetry in the case of cage motors (e.g. broken bars or end rings). The system also distinguishes and monitors the different faults by using one measuring element only.