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Recently, considerable attention has been attracted to the development of the new concept motor for EV or HEV. Wider torque and speed controllable operating range and high efficiency under driving area are needed for traction motor. The purpose of this paper is to realize the new concept variable field flux motor with claw pole rotor and brushless robust structure for high-speed range.

In the previous paper, the authors proposed a half-wave rectified brushless variable field flux method with a diode inserted into the field winding. This paper presents a designing for a novel claw pole rotor type motor using the variable field flux method (CP-HVFM). The claw pole type rotor has simple and robust structure for high-speed operation. This paper describes a first prototype design result for CP-HVFM using 3D-FEM. And the authors report the torque and efficiency characteristic results using 3D-FEM.

The authors have studied the designing for CP-HVFM using 3D-FEM. The designed prototype CP-HVFM reached a rated power of 2 kW or more at a rated speed 1,800 rpm under design restrictions of experimental equipment and initial specifications. In addition, the authors found the ratio of the tip and root embrace of the claw pole shape for maximum average torque and minimum torque ripple. Finally, the authors revealed an influence of the armature current on the torque and the efficiency characteristic results for the designed prototype CP-HVFM using 3D-FEM.

The half-wave rectified brushless variable field flux method proved to be effective for the claw pole rotor type motor. And also the authors found the best claw pole shape for torque characteristic. This results are applied to another concept motor for EV or HEV.

It takes long time for estimating a copper loss in the coil winding of the motor by using the finite element method (FEM). The purpose of this paper is to calculate fast the copper loss by zooming method.

The authors adopt the “zooming method” to FEM. The authors compare the accuracy and the calculation time with zooming method and normal FEM.

The zooming method contributes to speeding up and the high accuracy of calculation. In the results, the 43-fold speed increase is achieved in the calculation of synchronous motor compared to usual FEM.

The AC copper loss calculation of 3D motor analysis can be calculated in practical computation time.

The main advantage of employment of zooming method is significantly reduction of the computation time in the loss calculation of the coil winding.

This chapter examines the role of political recycling – the practice of repeated utilization of former high-level politicians in government – in forestalling or, at least, minimizing conflicts among political players. Drawing upon observations from recent political experiences of Japan, the chapter first demonstrates that political recycling in Japan is deeply embedded in the society's cultural practices rather than in the system of liberal democracy, which its leaders espouse. Political recycling in Japan, in fact, exhibits features that are antithetical to liberal democracy. The dynamic relationship between political recycling and conflict prevention in Japan are then analyzed as well as the implications of the analysis for places in Africa where political conflict has been rampant.