Analytical Calculation of Synchronous Reactances of Homopolar Inductor Alternator

In this paper, the direct-axis (d-axis) and quadrature-axis (q-axis) synchronous reactances of homopolar inductor alternator (HIA) are calculated. First, an approximate 2-D model of HIA is developed and its relative air-gap permeance function is described. Then, the analytical expressions for the synchronous reactances in the d-axis and q-axis are derived from magnetomotive force-relative air-gap permeance function theory, including armature reaction reactance and armature leakage reactance. Finally, theoretical results are compared with the simulation and experimental results.