Starting and steady state characteristics of axial-type high T/sub c/ superconducting bulk motor

This paper presents the starting and steady state characteristics of axial-type superconducting bulk motor in which Bi-2223 is utilized. 3-phase and 4-pole armature windings are introduced in order to produce a rotating magnetic field in an air-gap with a speed of 1800 rpm. The no-load tests are performed, respectively, at 77.3 K and 64.0 K in order to examine the difference of the flux pinning strength on the rotating characteristics. The relation between the phase voltage and the armature current is discussed from the point of view of the shielding property of the Bi-2223 bulk rotor. The experimental results of resistance and reactance as a function of the phase voltage are also to be shown and discussed.