Abstract: Radial loop coils are wound in radial planes partly in the conventional slots of the stator and/or rotor core at right angles to the planes of the conventional drum coils. No conventional drum coils are wound. A cylindrical body of nonmagnetic material is fixedly interposed between the rotor core and the shaft and/or between the stator core and the yoke so that the flux of the stator and the rotor core flows in opposite side portions of the stator and rotor core, not through the shaft or the yoke, to generate e.m.f. in the radial loop coils by the transformer action. The flux which is produced by the transformer m.m.f. of the radial loop coils is constrained to flow into the air gap by virtue of the presence of the cylindrical body of nonmagnetic material where it acts to eliminate changes in the main magnetic field flux density distribution in the air gap.

Abstract: To eliminate armature or rotor reaction or leakage flux (leakage reactance) in an electric rotating machine, a short-circuit coil winding is wound on and through the rotor or an armature core of the machine. The short-circuit coil winding is wound at a right angle to the main coil to exclude any intervention. Due to placement of a non-magnetic material in the armature core, the leakage flux which flows in the non-magnetic material is reduced and the flux of the stator and the rotor flows separately along both sides to the inner part of the armature or rotor ring core. Due to the non-magnetic material, the flux which occurs due to the current of the transformer m.m.f. of this short-circuit ring coil extends substantially into the airgap, therefore to abate the effect of armature reaction flux in the airgap.

Abstract: To eliminate rotor reaction in an induction motor, double ring coils are wound on and through the rotor core in addition to the main coils at right angles to the main coil plane. By placement of a nonmagnetic material at the center of the rotor, the flux of the stator and rotor flows in separate paths at opposite sides of the rotor core and not through the shaft, to produce a transformer (induced) m.m.f. in the double ring coils. The flux which occurs due to the current of the transformer (induced) m.m.f. of the double ring coils extends substantially into the air gap by virtue of the nonmagnetic material to abate the effect of the rotor reaction in the air gap.