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Summary Understanding the merits of using an interior permanent magnet synchronous machine (IPMSM) for propulsion in all‐electric vehicles and challenges in conventional electric machine design approach, this paper proposes a novel model based design approach for three‐phase IPMSMs. Firstly, a novel bottom‐up IPMSM design methodology involving closed‐form analytical equations and per unitization approach based on maximum‐torque‐per‐ampere control theory is proposed. Using this approach, preliminary parametric and structural design of the machine with (1) a desired constant torque region; (2) desired reluctance torque percentage; (3) a specific constant power region; and (4) optimal angle of the stator current vector can be obtained. Thereafter, the proposed model based design approach has been verified through finite element analysis conducted on the electromagnetic model of a downscaled electric vehicle (EV) motor designed. Finally, the designed machine has been prototyped and experimentally tested for designed parameters and output performance with maximum‐torque‐per‐ampere and vector control strategies.

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GaN nanorods were grown by plasma assisted molecular beam epitaxy on intrinsic Si (111) substrates which were characterized by powder X-ray diffraction, field emission scanning electron microscopy, and photoluminescence. The current–voltage characteristics of the GaN nanorods on Si (111) heterojunction were obtained from 138 to 493 K which showed the inverted rectification behavior. The I-V characteristics were analyzed in terms of thermionic emission model. The temperature variation of the apparent barrier height and ideality factor along with the non-linearity of the activation energy plot indicated the presence of lateral inhomogeneities in the barrier height. The observed two temperature regimes in Richardson's plot could be well explained by assuming two separate Gaussian distribution of the barrier heights.