Armature Fault Diagnostics of a Commutator Motor using the Frequency Response Analysis

A diagnostic method for armatures of commutator motors using the frequency response analysis method (FRA) is presented in this paper. The proposed method can, beside the detection of the fault itself, recognize and categorize the fault types. In a first step, the magnetic and capacitive couplings of the armature single components are analyzed. Thereafter, the position-dependent impedance curves of healthy and faulty armatures are obtained by measurements and used for the detection of winding faults. Taking as criteria the main resonant points of the frequency and position dependent armature impedance curve, a diagnostic method that considers three different fault types is developed.