Applied Computational Electromagnetics Society Journal (ACES)

Special Issue

Antonino Musolino — 2026-10-15

Electric Energy production, especially from renewable fonts, together with transport electrification is one the key
factors in the agenda for sustainable development.
This special issue brings together nine contributions on electrical machines, also considering examples of related
power converters, for energy generation and electric transportation. Their shared focus is the relationship between
electromagnetic design, operational flexibility, and reliability, addressing the demands of compact renewable energy
converters and efficient electric drives.
Three studies investigate tubular linear–rotary switched reluctance machines, with potential applications in inte-
grated actuation and marine energy systems. A comparative investigation combining geometric sensitivity analysis
with alternative winding arrangements, identifying improvements in torque, thrust, and output smoothness is carried
on in the first study. A second contribution considers H-shaped modular stators that accommodate rotary and linear
magnetic circuits with limited electromagnetic coupling. A third examines a two-degree-of-freedom topology through
static field analysis and dynamic simulations, clarifying saturation behavior and the interaction between motion
modes. Together, these studies support the development of integrated electromechanical systems relevant to combined
wind and wave energy conversion.

Comparative Analysis of a Novel Linear Rotary Switch Reluctance Machine

Hao Chen — 2026-06-30

This paper proposes a novel tubular linear rotary switch reluctance machine (TLRSRM) with modular stator and rotor designs and studies its electromagnetic characteristics. Firstly, the topology and operating mechanism of the two-degree-of-freedom machine are presented. based on the proposed motor design process, the structural dimensions are initially determined, and the 3D finite element model (FEM) with its flux density distribution is provided. Secondly, a sensitivity analysis of critical structural parameters is conducted by using a parameter sweep method to investigate their influence on torque performance. Finally, to evaluate the motor’s static characteristics – including flux linkage, inductance, and torque/thrust – comparison analysis is performed between two TLRSRM variants featuring different winding configurations. Simulation results validate the feasibility of the proposed topology.

Design and Electromagnetic Analysis of Stator-Modular Tubular Linear Rotary Machine

Hao Chen — 2026-06-30

This paper proposes a novel modular stator 6-pole tubular linear rotary switch reluctance machine (TLRSRM). The proposed structure employs circumferentially distributed H-shaped stator modules, with each module’s four poles wound with concentrated windings. The outer stator pole windings and outer rotor form a three-phase radial magnetic circuit driving rotational motion, while the inner stator pole windings and inner rotor constitute a single-phase transverse magnetic circuit driving linear motion. This paper elucidates the motor’s operating principle and electromagnetic design process. Based on the three-dimensional magnetic field distribution characteristics, finite element analysis (FEA) was employed for three-dimensional magnetic field calculations to obtain flux linkage and torque characteristics. Additionally, the electromagnetic coupling effects between rotational and linear motions were investigated for the conjugate rotary-linear magnetic circuit within the modular stator. Simulation results indicate minimal electromagnetic coupling effects in the proposed TLRSRM structure. This study provides a robust theoretical foundation and empirical data support for further optimization and practical application of this motor topology.

Electromagnetic Analysis of a Novel Two-Degree-of-Freedom Tubular Linear Rotary Switched Reluctance Machine

Cheng Liu — 2026-06-30

A novel two-degree-of-freedom tubular linear-rotary switched reluctance machine (TLRSRM) is proposed, and its electromagnetic characteristics are investigated. First, based on energy conversion principles, the topology and working mechanism of the TLRSRM are explained. Structural dimensions are determined using conventional motor design experience. Next, a 3D finite element model (FEM) and a structural validation process are established to verify the electromagnetic feasibility of the topology. The magnetic field distributions are compared between the unaligned and aligned positions. Furthermore, parameter sweeping is applied to systematically analyze static electromagnetic characteristics. These include the nonlinear variation of inductance, flux saturation behavior, and electromagnetic force output in a twodimensional position-current parameter space. Finally, the multi-degree-of-freedom coupling mechanism is quantitatively analyzed. Simulation results of both static and dynamic performances successfully confirm the structural feasibility of the proposed topology, thereby establishing a solid theoretical framework for subsequent optimization and control.

A Lumped Parameter Thermal Network Model for Dual-Stator Mover-PM Linear-Rotary Generators

Chenxi Li — 2026-06-30

Mover-permanent magnet linear-rotary generators (MPMLRGs) with dual-stator topology and two degrees of freedom (2-DOF) have attracted growing interest due to their high integration and compactness, enabling coupled linear-rotary motion for direct-drive energy conversion and multifunctional actuation systems. However, the coupled linear-rotary motion and unsymmetric dual-stator topology lead to complex thermal behaviors, and the associated thermal characteristics remain insufficiently investigated compared to electromagnetic studies. In this paper, a lumped-parameter thermal network (LPTN) model is developed for a dual-stator MPMLRG to accurately capture its asymmetric heat transfer and temperature rise under helical motion. A novel approach is proposed to determine the air-gap convective heat transfer coefficients under coupled linear-rotary operation, along with a time-weighted correction method to account for the partial axial overlap of stator-mover surfaces. The thermal model is validated against 3-D thermal finite element analysis (FEA), showing good agreement while significantly reducing computational effort. The results provide useful insights into the thermal management of the dual-stator MPMLRG and establish a foundation for future design optimization and cooling enhancement.

Electromagnetic Analysis of a 12-Pole Single-Phase Switched Reluctance Linear Motor

Hao Chen — 2026-06-30

A novel modular 12-pole transverse-flux tubular switched reluctance linear machine (TSRLM) is proposed in this paper. The machine adopts a U-shaped modular-stator structure with windings arranged on the stator yoke, which shortens magnetic flux paths, reduces magnetic reluctance, and improves iron core utilization. A three-dimensional finite-element model is established to analyze the electromagnetic characteristics of the proposed TSRLM, including flux linkage, static electromagnetic force, and magnetic field distribution. On this basis, a sensitivity-based single-objective optimization is conducted to determine the structural parameters of the motor. Then, a 12-pole TSRLM prototype is fabricated, and dynamic motoring experiments are carried out under different current chopping limits. Experimental results agree well with simulation results, validating the accuracy of the finite-element model and the feasibility of the proposed design.

Unified 3D Analytical Models of Surface-Inserted Axial Flux Machines With Odd-/Even-Piece Halbach Arrangements

Youyuan Ni — 2026-06-30

Considering the 3-dimensional (3D) air-gap fringing field, unified 3D analytical models equivalent to linear machines are proposed for surface-inserted axial flux machines (SIAFMs) with odd-/even-piece Halbach arrangements. The 3D scalar potential governing equations for several regions can be uniquely solved according to Fourier decomposition coefficient matrixes derived from field boundary conditions. Based on this, the electromagnetic parameters can be derived. Predictions indicate that, compared with the non-optimized SIAFMs with three-/four-piece Halbach arrangements, the optimized SIAFMs with three-/four-piece Halbach arrangements exhibit excellent electromagnetic performances. The 3D finite element (FE) and analytical predictions for the SIAFM models are compared.

Design and Open-Circuit Fault Analysis of Modular E-Type Stator Switched Reluctance Motor for High-Reliability Applications

Hao Chen — 2026-06-30

This study proposes a modular switched reluctance motor (SRM), featuring an E-shaped stator core structure, suitable for high-reliability applications. The stator comprises six independent E-shaped cores with windings mounted on the core yokes. A two-dimensional simplified model evaluates static performance, including torque, magnetic flux (MMF), and inductance under both normal and winding fault conditions. Simulation results demonstrate the high reliability of the designed SRM.

Performance Comparison Analysis of Modular Double-Stator Switched Reluctance Motor with Differing Winding Polarities

Fengyuan Yu — 2026-06-30

Modular double-stator switched reluctance motors offer the advantages of high torque density, low mutual coupling, and high reliability, making them promising candidates for electrified transportation applications. The dual-winding configuration enables both the inner and outer stator poles to be equipped with excitation windings. Variations in the excitation direction of these windings lead to distinct winding polarity distributions, thereby resulting in different magnetic flux paths and electromagnetic characteristics. This paper presents two typical polarity distributions for modular double-stator switched reluctance motors, namely NSNS and NSSN. Motor models are established in the finite element software Altair Flux to analyze the flux path, flux density, and static electromagnetic torque under both winding polarities. In addition, dynamic performance metrics including torque ripple, core loss, copper loss, and efficiency are evaluated under various rotor geometries and operating speeds. The influence of key rotor geometric parameters on the torque and efficiency characteristics of the two polarity configurations is also investigated.

A Dual-Port Integrated Switched Reluctance Motor Power Converter for Electric Vehicles With Flexible Braking and Energy Recovery

Chenhe Zhang — 2026-06-30

As environmental protection increasingly becomes a global focus, new energy vehicles have gradually emerged as a rising star in the modern transportation sector. They not only represent technological innovation but also carry the hope of achieving sustainable mobility. This paper proposes a novel dual-port integrated power converter, consisting of a front-end circuit and a traditional asymmetric half-bridge converter. By changing the operating state of the front-end circuit’s switch transistors, different operating modes can be switched. In the motoring state, there are single-power supply mode and hybrid power supply mode, and the converter is reconfigured into a five-level converter. In the regenerative braking mode, there are moderate braking mode and severe braking mode, and energy recovery can be achieved in both modes, with the converter being reconfigured into a four-level converter. The power converter proposed in this paper can accommodate wide speed range regulation for both electric and braking operations, while also recovering energy from regenerative braking. It has been simulated and verified on a three-phase 12/8 switched reluctance motor, confirming its practicality and effectiveness.