STATOR TURN-TO-TURN FAULT DETECTION OF SYNCHRONOUS GENERATOR USING TOTAL HARMONIC DISTORTION (THD) ANALYZING OF MAGNETIC FLUX LINKAGE

Abstract

Diagnostics of synchronous generator turn-to-turn faults can be accomplished byanalyzing the anomalies of machine local variable such as magnetic flux linkage. On the otherhand, because current transformers and voltage transformers are usually installed in the machinefor different purposes as default, the monitoring schemes that depend on the study of these inputshave become a topic of interest. As a consequence, in the last two decades, a variety of methodshave been proposed based only on the global external variable (such as stator current and voltage).It must be noted that the global external variable analysis techniques are not capable of detectingall of the potential faults in electrical machines and some researches, including this work, aim totransfer a part of the global external variables analysis knowledge to techniques that monitor thesignatures produced by the fault to the electromagnetic flux signals (local variable). Hence, thiscontribution deals with the analysis of the stator turn-to-turn short circuit fault of salient-polesynchronous generator. In this paper, a fault indicator based on harmonic analysis of the magneticflux linkage is investigated. Experimental results derived from a 4-pole, 380V, 1500 rpm, 50 Hz,50 KVA, 3-phase salient-pole synchronous generator, show that the proposed method is useful andeffective.