As a strongly coupled, multivariable, high-order nonlinear, time-varying complex system, a linear induction motor is susceptible to outside disturbances and mismatched parameters. Because of its straightforward control mechanism and fixed PI value, the traditional PI regulator is frequently utilized in linear induction motor speed control systems. However, because of these limitations, it frequently falls short of meeting the high-performance control needs of the motor in complex operating conditions. In order to solve the contradiction between the sliding-mode motion reaching time and vibration, the sliding-mode variable structure control is applied to the linear induction motor speed control system in this paper. The sliding-mode controller is designed using the exponential reaching law method, and the designed system is analyzed through simulation. The findings demonstrate how the controller enhances the system’s robustness and disturbance resistance by bringing about the advantages of rapidity, stability, no overshooting, and a strong resistance to load disturbance.

High-speed solid rotor induction motors (HS-SRIMs) are favored for their robust structure but suffer from significant eddy current losses at high speeds, leading to efficiency reduction and thermal challenges. This study establishes a comprehensive multi-objective optimization framework to address this issue. The eddy current loss characteristics are first investigated using finite element analysis (FEA), focusing on the impact of key parameters like air gap length and rotor slotting. A sensitivity analysis quantifies their influence on motor performance. Subsequently, the Non-dominated Sorting Genetic Algorithm II (NSGA-II) is employed for multi-objective optimization, aiming to minimize eddy current loss while maximizing efficiency and electromagnetic torque. The optimization results demonstrate a significant improvement: a reduction in eddy current loss of 59.8%, an increase in efficiency of 17.2%, and a boost in output torque of 50.8%. Coupled electromagnetic–thermal simulations further validate a substantial decrease in operating temperatures. The proposed method provides an effective design approach for high-performance HS-SRIMs.

The conventional PI control, which has been extensively employed in the high-performance control of linear induction motors, has the benefit of a straightforward concept, quick dynamic response, and simple control. Nevertheless, the linear induction motor is more susceptible to outside disturbances and mismatched parameters since it is a highly linked, high-order, nonlinear, time-varying, complex system. Because of this, this paper proposes a double-closed-loop control of the linear induction motor, whose speed and current loops are the model-predictive speed controller and the model-predictive current controller, respectively, to solve the problems of speed overshoot and oscillation when the linear induction motor is operated under PI control. The findings demonstrate the benefits of the suggested control strategy, which significantly enhances the linear induction motor’s speed control performance. These benefits include improved dynamic performance, limited overshooting, and robust resistance to load disturbance.

Accurate loss evaluation of high-frequency transformers (HFTs) under non-sinusoidal excitation is essential for the optimal design of dual-active-bridge (DAB) converters, yet remains challenging due to spatially non-uniform magnetic flux distribution across the core and spectrally rich harmonic content in the winding current. This paper proposes a dual-refinement electromagnetic loss analysis method that combines a topology-aware region-partitioned improved generalized Steinmetz equation (IGSE) with a harmonic-resolved Dowell model. The ferrite core of a shell-type HFT is partitioned into three magnetically distinct zones—core legs, side pillars, and yokes—with the IGSE applied independently to each zone using zone-specific flux density waveforms derived from the single-phase-shift (SPS) control model, thereby capturing spatial non-uniformity in core loss. For winding loss, the current is decomposed via fast Fourier transform, and per-harmonic AC resistance is computed up to the seventh order with frequency-dependent skin depths, accounting for the spectral contribution to copper loss. A 300 V/6 kVA ferrite-core foil-winding HFT prototype was fabricated, and the proposed method was validated through COMSOL finite element simulations and experimental measurements using open-circuit and short-circuit tests. Results show that the calculated core loss and winding loss agree with measurements within 10–15% and 8–10%, respectively, demonstrating improved accuracy over the conventional uniform-IGSE and total-RMS Dowell approaches.