Wigner distribution for the diagnosis of high frequency amplitude and phase modulations on stator currents of induction machine

Baptiste Trajin (1) , Marie Chabert (2, 3) , Jérémi Regnier (4) , Jean Faucher (1)

1 LAPLACE - LAboratoire PLasma et Conversion d'Energie
2 IRIT-SC - Signal et Communications
3 Toulouse INP - Institut National Polytechnique (Toulouse)
4 LAPLACE-CODIASE - COmmande et DIAgnostic des Systèmes Electriques

This paper deals with mechanical fault monitoring in induction machines from stator current measurements. The considered faults lead to amplitude and/or phase modulations of the measured stator current. The different faults can be characterized by their time-frequency signatures via the Wigner distribution. The time-frequency representations apply to complex signals that may be obtained through the Hilbert transform of the real measured signal. In case of high frequency modulations, it can not be taken advantage of the time frequency signatures. This study proposes an alternative complex signal representation for modulated stator currents. The so-called space vector is obtained through the Concordia transform. From three stator current measurements, the Concordia transform builds a complex vector which conveniently carries the information about phase and amplitude modulations. This paper applies and compares the Wigner distribution computed with the Hilbert and Concordia transforms in case of simulated and experimental signals with various modulation frequency ranges.

Mots clés: Diagnosis; High frequency modulations; Induction motor; Wigner Distribution

Domaines: Physique des plasmas [physics.plasm-ph]

Baptiste Trajin, Marie Chabert, Jérémi Regnier, Jean Faucher. Wigner distribution for the diagnosis of high frequency amplitude and phase modulations on stator currents of induction machine. 2009 IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED 2009), Aug 2009, Cargese, France. ⟨10.1109/DEMPED.2009.5292804⟩. ⟨hal-02299500⟩