Brushless Three-Phase Synchronous Generator Under Rotating Diode Failure Conditions

Mohamed Salah (1) , Khmais Bacha (1) , Abdelkader Chaari (1) , Mohamed Benbouzid (2)

1 research unit on control, monitoring and reliability of systems
2 LBMS - Laboratoire brestois de mécanique et des systèmes

In brushless excitation systems, the rotating diodes can experience open- or short-circuits. For a three-phase synchronous generator under no-load, we present theoretical development of effects of diode failures on machine output voltage. Thereby, we expect the spectral response faced with each fault condition, and we propose an original algorithm for state monitoring of rotating diodes. Moreover, given experimental observations of the spectral behavior of stray flux, we propose an alternative technique. Laboratory tests have proven the effectiveness of the proposed methods for detection of fault diodes, even when the generator has been fully loaded. However, their ability to distinguish between cases of diodes interrupted and short-circuited, has been limited to the no-load condition, and certain loads of specific natures.

Mots clés: Alternators; brushless machines; fault detection; fault diagnosis; monitoring; spectral analysis

Domaines: Energie électrique

Mohamed Salah, Khmais Bacha, Abdelkader Chaari, Mohamed Benbouzid. Brushless Three-Phase Synchronous Generator Under Rotating Diode Failure Conditions. IEEE Transactions on Energy Conversion, 2014, 29 (3), pp.594-601. ⟨hal-01063655⟩