Symmetrical components and current Concordia based assessment of single phasing of an induction motor by feature pattern extraction method and radar analysis

Diagnosis of single phasing of an induction motor has been done by sequence components, stator current Concordia and radar analysis. Conventional sequence component method is first used to detect single phasing of an induction motor by measuring negative sequence components and angle shift of healthy phases. Then, Concordia analysis is done where, stator current Concordia is formed and rule set is developed for detection of single phasing. Concordia at normal condition is circular and that of stator current during single phasing is straight line. Radar analysis is then performed. Radars of stator currents at normal condition give three closed loops having one cleavage and they are located 120 degrees apart from each other. Radars of stator currents at single phasing give three closed loops; two of which have cleavage and the other is circular free from cleavage which corresponds to the faulty phase. Some specific parameters are defined and again radar analysis of these parameters is performed. These radars are of triangular shaped. All Concordia and radar are assessed for diagnosis of single phasing of an induction motor. (C) 2011 Elsevier Ltd. All rights reserved.