Identification of TBAES rotating diode failure

This study focuses on the identification of the rotating diode failures of an aircraft wound-field synchronous starter-generator system. Owing to the difference in topography between the DC field excitation system and the threephase brushless asynchronous excitation system (TBAES), the rotating diodes failure identification methods for the DC field excitation system cannot be implemented in TBAES. To solve this problem, this study presents the theoretical analysis of the effects of diode failures on the TBAES rotor current. The theoretical analysis shows that the third and the fundamental components of rotor current could be treated as diode failure features. When a rotating diode operates in open-circuit conditions, the third harmonic current of the normal phase windings increases, but it does not increase while in the fault phase. Meanwhile, the amplitude of the fundamental current of failure phase reduces. Under short-circuit conditions, both the third harmonic and the fundamental component of the rotor current of TBAES rotorwindings increase. On the basis of the theoretical findings, the detection of rotating diode failures is achieved by the harmonic analysis of the estimated rotor currents.