Impact Mechanisms of Rotating Rectifier Faults on the Multiphase Brushless Excitation System in Nuclear Power

Multiphase brushless excitation systems (MBESs) are widely employed in high-capacity nuclear power generators due to their superior output current quality and low maintenance requirements. However, the rotating rectifier, which operates at high speeds over extended periods, is prone to failure, potentially disrupting the system's current distribution and threatening operational stability. Existing research focuses on rotating rectifier fault (RRF) diagnosis but lacks analysis of the impact of such faults. In this study, based on the conduction mechanism of diodes, the diode current distribution patterns of RRFs are analyzed and the extent to which different fault types influence MBESs reliability is derived. Finite element simulations and prototype experiments indicate that the influence of RRFs on diode current distribution patterns follows diode conduction mechanism, and certain fault types significantly affect system reliability. These findings provide a theoretical foundation for optimizing equipment design parameters and developing more adaptive operational strategies.