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We fabricated c-axis-oriented KSr 2 Nb 5 O 15 (KSN) ceramics using a rotating strong magnetic field with subsequent sintering. The degree of orientation of the green compact was about 0.1 for (00l), as evaluated from the Lotgering factor in X-ray diffraction. The orientation of the structure was enhanced by sintering at 1673 K; the Lotgering factor of the sintered body increased to 0.8. Microstructural examination indicated a well-oriented structure in which the longitudinal axes of the rectangularshaped grains were oriented perpendicular to the axis of rotation of the magnetic field. KSN oriented on the a, b axes could be similarly fabricated using a strong static magnetic field.

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Design and experimental studies on a hybrid excitation flux switching motor as a traction motor for hybrid electric vehicles drive are presented. A stator body of the motor consists of not only laminated silicon-iron electromagnetic steel and three-phase armature windings, but also both of field excitation coils and permanent magnets working together as a variable field magnetomotive force source. On the other hand, a rotor is composed of just laminated silicon-iron electromagnetic steel with salient poles like switched reluctance motor. To bring out the best in drive performances of the hybrid excitation flux switching motor as a variable flux motor for the application, each material adopted for the stator and rotor body should be designed properly in terms of motor efficiency, maximum torque and power densities and so forth. As some of them, in this paper, thinner silicon-iron electromagnetic steel sheet and permanent magnets with high remanent and low amount of Dysprosium used are applied for achieving higher motor efficiency. Moreover, all coils wound flatwise and edgewise using rectangular wires are introduced to realizing high filling factor for reduced copper losses. Experimental tests using a 60kW prototype of the motor demonstrates the designed motor has good motor efficiency under frequent operating points expected for the target vehicle drive.

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