Additive manufacturing (AM) enables the creation of parts with exceptional geometric versatility, creating new possibilities for developing non-symmetrical electrical machines (EM) with compact structures, reduced mass density, high torque, better power density, and minimal material waste during fabrication. This review highlights the current state of AM methods and their critical role in the production of EM. The impact of the additively built EM components concerning performance indices, including torque, power density, and efficiency is highlighted. Additionally, an overview of the constraints associated with the traditional production process of EM-specific components and the role of AM in addressing those limitations is emphasized. As per the current state of AM in the context of EM production, the non-conventional structures of the stator and rotor core of EMs are feasible to fabricate to accomplish improved utilization of magnetic flux. Moreover, AM enables the fabrication of windings/coils of any profiles with integrated functionality, including the design of thermal management mechanisms to enhance EM performance and achieve thermally controlled EM. However, the current state of AM technology is not very advanced and requires additional improvement, particularly in areas of EM production, which are minimizing eddy current losses, high-quality surface refinement, build volume restrictions, and simultaneous multi-materials processing.

This article presents linear oscillating actuator (LOA) which generates bidirectional linear thrust force. Design topology of the proposed LOA contains an outer mover and an inner stator design. Two axially magnetized and tubular-shaped permanent magnets (PMs) are mounted on the mover. Due to the higher magnetic flux density of axially magnetized PMs in a specific direction, it generates higher thrust force than radially magnetized PMs. The proposed LOA operates on single-phase alternating source. All the design specifications of the LOA are optimized through finite element method (FEM) and optimum values of the design parameters are obtained. Output parameters such as the stroke length and thrust force are analyzed for multiple magnitudes of the input parameters such as current using FEM. Additionally, other parameters like back emf, coil current and winding resistance are analyzed at resonance. Effect of motor constant is investigated toward both directions of the force, which shows identical replication. Output parameters of the LOA are compared with already designed topologies of the LOA for refrigeration system. Proposed LOA demonstrates promising improvements in terms of motor constant and thrust force compared to the volume of the LOA. Moreover, proposed LOA is comparatively convenient to fabricate as well.

This paper proposes a new modular hybrid excited flux switching motor (MHEFSM) with flux gaps, adding the fault-tolerant capability to the proposed motor. The proposed motor uses an E-Shaped stator, as the middle teeth of E-core produce fault-tolerant capability, and in C-core, this capability is eradicated. The no-load flux linkage is calculated by the magnetic network model (MNM) to reduce time and disk storage. The drawback of the constant flux linkage of PM motors is overcome by employing field excitation (FE). The FE helps in regulation flux at higher speeds. The motor leading geometry variables are optimized by using Genetic Global Optimization (GGO). The GGO helped in refining the structure of the motor and has improved the flux linkage by 68.18%, average torque and torque density by 62.35% each, reduced torque ripples by 20.62%, and cogging torque by 18.52%. The volume of permanent magnet (PM) in the proposed MHEFSM is reduced by 36.24%, and 48.49% higher average torque and torque density is obtained compared to the state of art motor proposed in the literature. Furthermore, a 3D analysis of the proposed MHEFSM is done to further evaluate the electromagnetic performance.

To overcome energy crises, attention is being paid to saving energy from household appliances. Traditional compressors are in need of being replaced by efficient linear compressors. This paper presents a new tubular moving magnet linear oscillating actuator (TMM-LOA) for compressor application. The proposed topology utilizes outer mover topology with separators between the mover and stator modules. The number of stator and mover modules can be increased or decreased based on the requirement. The addition of a separator avoids the flux cancellation and makes the proposed topology fault-tolerant. The design variables are optimized by using a parametric sweep, and the performance in terms of thrust force is observed. Both the static and transient analyses were performed to analyze the machine performance at various currents and stroke. Both mechanical and electrical resonance phenomena are discussed. The efficiency of the proposed TMM-LOA is calculated for one, two and three modules. Finally, the proposed topology is compared with other topologies proposed in the literature to show the superiority of the proposed design.

Due to simpler mechanical structure and magnetic gearing effects, Permanent Magnet Vernier Machines (PMVMs) attract researcher interest because of their higher torque density for direct drive applications. However, regular PMVMs utilize more rare earth Permanent Magnet (PM), which increases machine cost and weight. Moreover, the PMs are mounted on the rotor surface, which enhances flux leakage and flux circulation, which degrade electromagnetic performance that ultimately decreases average torque, torque density, power density and efficiency. A new Split Pole PMVM (SP-PMVM) with Halbach PM arrangement in the stator slot opening and consequent pole rotor is proposed to overcome the issues above. The proposed SP-PMVM enhanced flux modulation phenomena to improve electromagnetic performance. Comparing the proposed machine with the existing designs reveals that the proposed design reduces the PM utilization by 22.2% and improves the flux linkage by 41.3% due to suppression of leakage flux and flux circulation. Moreover, the average torque is boosted by 42.35%. Furthermore, torque and power densities are increased by 83.01% and 44.84%, respectively. In addition, in comparison with the existing conventional design, the efficiency of the proposed model is enhanced by 25.01% at the cost of 19.75% cogging torque.

This article examines a new linear oscillating actuator (LOA) design that uses rectangular-shaped core materials and permanent magnets (PMs). The primary objective of the paper is to examine a novel LOA topology with a rectangular-shaped core and PMs as an alternative to the tubular LOA. A static core material is housed between the mover’s components and two stator cores with two coils, each of which is placed on either side of the mover. The dimensions of all the parameters are swept for optimization and the optimal parameter dimension is chosen based on the optimal value of the electromagnetic (EM) force. An analysis is done for output results like EM force and stroke. Parameters like input current, EM force and stroke-to-current ratio are investigated for different frequencies of the input electrical loading to demonstrate the significance of resonance operation. EM force per PM mass of the investigated design of LOA is 67 percent higher than that of a conventional rectangular-shaped LOA. Additionally, the EM force density of the proposed design is 23.8 percent higher than that of the conventional design of LOA. Furthermore, the stroke of the proposed LOA is also feasible and more than most of the designs of the LOA. Additionally, the proposed design of the LOA is simple in structure, low-cost, and feasible for fabrication.