Depending on its mechanical and thermal advantages, solid rotor induction motors (SRIMs) are widely used in demanding high‐speed applications. Since eddy currents are set free in SRIMs, great part of rotor losses is caused by space harmonics created in the air‐gap. Rotor losses are increased tremendously in high‐speed applications with the remarkable increase in driving frequency. Here, an innovative design representing a novel stator and rotor combination that is not achieved in previous studies is proposed by structural changes to stator to eliminate major effective space harmonics. An unconventional stator slotting pattern and winding distribution is calculated by nature‐inspired numerical optimisation techniques while keeping the fundamental winding factor relatively high. An example design where novel concepts are implemented is presented and a comparison is given in terms of important operational quantities with that of a standard SRIM.

In recent years, improvements in the manufacturing, transport and process industries have brought about an increase in the optimum operating speed for drive systems. In this respect, the recently developed, high-speed, gearless or direct electrical drives are currently very popular, because of the reduction in the total structural volume of the drive system. In this study, the performances of four high-speed induction motors with different types of rotor, i.e., cage, smooth solid, slitted solid and coated solid, were examined in cases where the geometrical size is kept constant. All the motors with different rotor types have a particular number of turns per phase in their slots, which is arranged to obtain the same rated current value when compared with the reference, conventional cage-induction machine. In order to compare the performance characteristics brought about by the change in the rotor's structure for different numbers of turns, all the induction motors were analyzed with the finite-element method (FEM). Using a coating with a high electrical resistivity was shown to increase the torque output. It was also clear that cutting the rotor in the axial direction increases both the flux penetration and the efficiency.

Although the performance of an Induction Motor (IM) can be maximized for any speed by use of an inverter, there is still room to contribute by optimizing the rotor slot shape while decreasing the mechanical disturbing effects and acoustic noise. This paper focuses on the effect of different individual rotor slot shapes on the performance of an IM including overall space harmonic, vibration and acoustic effects. A number of rotor slot shapes were implemented to the rotor of a commercial IM and efficiency of all designs were maximized for constant torque region by optimization. Afterwards, operational performance including starting, breakdown and rated operations; moreover, harmonic content and torque ripple were analyzed numerically in association with the mentioned rotor slot shapes. Best performing 4 rotor slot shapes in terms of chosen operational quantities were designated. Furthermore, the determined motors were carried out to vibration and acoustic noise analysis. Superposed acoustic disturbances in terms of sound power level for different harmonic frequencies were obtained and results are given in comparison. All-in-all, this paper contributes to associating the end-to-end disturbing effects to certain rotor slot shapes. This study determines disturbance and performance criterions for choosing an appropriate motor for an IM to be used in an electric vehicle. It was shown that rotor slot shape still deserves considerable attention to increase the performance of an IM while decreasing the adverse effects of space harmonics, mechanical vibration and acoustic disturbance.

This work presents a comparison between different tuning methods for cascade PI(D) controller parameters of the permanent magnet direct current (PMDC) motor drives. First, the classical method (CM) for cascade PI(D) tuning is explained and applied. It has been shown that the classical tuning approach requires some assumptions. Next, a heuristic optimization technique, the Bacterial Foraging Algorithm (BFA), has been introduced and implemented for the problem. Lastly, for the comparison, the Genetic Algorithm (GA) is applied for the cascade PI(D) tuning problem. The results for these three methods are compared and discussed. It is shown that the controller designed by BFA showed better dynamic performance.

Axially-Slitted Solid Rotor Induction Motor (ASSRIM) has a better electric and electromagnetic performance in comparison to Smooth Solid Rotor Induction Motor (SSRIM) in high-speed drive application. A better flux penetration into rotor and increased rotor cooling capability can be performed with axial slits on rotor. The main drawbacks of the axially slits are decreased rotor bending resistance and increased air friction losses. In this study, 20.5 kW, 23600 min^-1 high-speed ASSRIM is designed and geometric design parameters of slits such as slit depth and width are optimized by finite element method (FEM). In order to determine optimal geometrical parameters, desired parameters are changed in order; others are kept constant while one is being optimized. 2D transient magnetic model is used for optimization.

This paper presents a systematic approach to selecting lithium iron phosphate (LFP) battery cells for electric vehicle (EV) applications, considering cost, volume, aging characteristics, and overall performance. A battery selection algorithm is developed to evaluate four different LFP battery cell models based on their long-term behavior in a 40 kWh battery pack. The algorithm integrates a vehicle energy consumption model, where battery performance is analyzed based on the Worldwide Harmonised Light Vehicles Test Procedure (WLTP) over a 10-year simulated period, considering five driving cycles per day. In order to ensure a fair assessment, the model accounts for variations in battery pack weight as the sole influencing factor on vehicle dynamics. The results compare vehicle range, battery pack mass, cost, cell degradation, and volume for each battery option. The findings indicate that the A123 Systems ANR 26650m1 battery cell offers the best trade-off between longevity and cost-effectiveness, making it a highly suitable choice for durable and efficient EV battery packs. This study underscores the importance of the most suitable battery selection in designing cost-effective, long-lasting EV energy storage solutions.