Modeling and Fault-Tolerant Control Method of Multiphase Permanent Magnet Pulsed Alternator

Abstract

Permanent magnet pulsed alternators (PMPAs) employ permanent magnet excitation, thereby eliminating the need for external excitation devices. Their simple and robust structure offers higher energy storage density and longer service life. The multiphase configuration is the development trend for such machines. Therefore, this article investigates multiphase air-core PMPAs. First, a generalized mathematical model is formulated under the natural coordinate system to facilitate the initial design of source-load matching parameters for multiphase PMPAs. Second, based on the operating characteristics and principles of an eight-phase half-wave rectifier circuit, a phase-shifting fault-tolerant rectifier control methodology is proposed for eight-phase PMPAs. By adjusting the trigger angle working interval, the PMPA can still meet load demands even in the event of phase faults. Simulations and experimental results validate the effectiveness of the mathematical model, while the proposed phase-shifting fault-tolerant control technique enhances system operational reliability.