Non-Destructive Testing for Winding Insulation Diagnosis Using Inter-Turn Transient Voltage Signature Analysis

Abstract

The paper proposes a novel approach to assess the integrity of Electrical Insulation Systems (EIS) by evaluating the response of the Transient Voltage Signature Analysis (VSA) to voltage source inverters correlated with changes in the Insulation Capacitance (IC). The involved model structures are derived from the in-situ estimation of high-frequency electromagnetic RLMC lumped network parameters. Different physical phenomena such as inductive and capacitive effects, as well as skin and proximity effects are combined. To account for these phenomena, we use an approach based on equivalent multi-transmission line electric circuits with distributed parameters (R: resistances, L, M: self and mutual inductances, and C: capacitances) which are frequency-dependent. Using the finite element method, firstly the turn-to-ground and turn-to-turn capacitance parameters are performed by solving an electrostatic model with a floating electric potential approach, and secondly, the resistance and self/mutual inductances are computed from the strongly coupled magneto-harmonic and total current density equations, including the conduction and displacement eddy current densities. The sensitivity of the capacitances is measured according to insulation thickness, and the dielectric properties are adopted to test the degradation order scenarios of the EIS and comparing their time and frequency domains of transient voltage waveform behavior with respect to healthy assessed insulation systems.

Inter-turn Short Circuit Diagnosis Using New D-Q Synchronous Min–Max Coordinate System and Linear Discriminant Analysis

“…In [2], the incidence of failures of induction motors was analyzed, and it was revealed that stator failure, rotor failure, and bearing failure account for 46%, 26%, and 11%, respectively. Among these types of failures, stator failure can lead to critical failures, which are the focus of diagnosis [3]. In particular, quick detection of inter-turn short circuit (ITSC) is the main research objective [4][5][6][7].…”

Linear Method for Diagnosis of Inter-Turn Short Circuits in 3-Phase Induction Motors

“…In particular, stator faults are caused by dielectric breakdown, and the stator winding insulation is degraded by various causes such as coil movement, thermal stress, overburden, and mechanical vibration. This degradation of the winding insulation eventually leads to turn-to-turn short faults [4].…”