Design and Characterization of a Single-Phase Main Exciter for Aircraft Wound-Rotor Synchronous Starter–Generator

This paper proposes and analyzes the design philosophies of the single-phase main exciter (ME) for an aircraft wound-rotor synchronous machine and investigates its operating characteristics in both generating and starting modes. The fundamental structure and starting-generating system are discussed. The load features of single-phase ME are summarized. The ME has the characteristics of linear current amplifier and approximately constant current source the generating mode, which can be used in the wide range of working temperature. Detailed waveforms and finite-element analysis verify that excitation current I
_ef
is almost irrelevant to speed but in direct proportion to frequency in the starting mode. Besides, simulated data indicate that the energy transferring efficiency between ME stator and rotor can reach about 55% by the single-phase ac excitation method. Finally, the experimental verification is carried out and the simulated and experimental data and waveforms of single-phase ME agree well with each other.