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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. [ABSTRACT FROM AUTHOR]

In this study, a torque enhancement principle for a stator permanent-magnet (PM) Vernier machine with a consequent pole structure is proposed. The novelty of the manuscript is the explanation of how stator PM Vernier machines benefit from consequent pole structure. Although a similar concept of stator PM Vernier machines with a consequent pole structure has been investigated in previous studies, a clear torque enhancement principle was absent. The keys to torque enhancement are the decrement of nonworking harmonics and increment of working harmonics. To demonstrate these phenomena, the torque contributions from the harmonics were calculated. Subsequently, the performances of the conventional machine and consequent pole machine were compared to verify the enhancement principle. The electromagnetic performances, including the back electromotive force and torque, were compared. The results show that the stator PM Vernier machine benefits significantly from torque enhancement using the consequent pole structure, and the torque enhancement principle was verified. [ABSTRACT FROM AUTHOR]

Oriented steel has higher permeability and lower losses in the direction of orientation (the rolling direction) than non-oriented steel. However, in the transverse direction, oriented steel typically has lower permeability and higher losses. The strategic use of oriented steel in a modular Permanent Magnet Synchronous Machine (PMSM) stator can improve machine performance, particularly when compared to a machine designed with non-oriented steel, by increasing both torque and efficiency. Typically, steel manufacturers provide magnetic properties only in the rolling and transverse directions. Furthermore, in modern Finite Element Analysis (FEA) software, the magnetic properties between the rolling and transverse directions are interpolated using an intrinsic mathematical model. However, this interpolation method has proven to be inaccurate; to resolve this issue, an improved model was proposed in the literature. This model requires the magnetic properties of the oriented steel in between the rolling and transverse directions. Therefore, a procedure for extracting the magnetic properties of oriented steel is required. The objective of this work is to propose a method of determining the magnetic properties of oriented steel beyond just the oriented and transverse directions. In this method, flux-injecting probes, also known as sensors, are used to inject and control the flux density in an oriented steel segmented stator in order to extract the properties of the oriented steel. These extracted properties are then used to model an oriented steel modular stator PMSM. The machine's average torque and core losses are compared with conventional, non-modular, non-oriented steel stator PMSM, and modular, non-oriented steel stator PMSM. It is shown that both the average torque and the core loss of the oriented steel modular stator PMSM have better performance at the selected number of segments than either of the two non-oriented steel stators. [ABSTRACT FROM AUTHOR]

Implementation of a new design for the process of assembling an axial-flux permanent magnet synchronous motor (AF PMSM) may lead to unstable motor parameters during operation at low and high speeds. In this paper, experimental data related to the AFPMSM used in an electric traction motor was monitored. The paper presents tracing of machine performance in order to find quality-related issues and to evaluate the assembly process. To assess the manual manufacturing process (low-volume production) and electrical machine performance, several motors, characterized by the same size and topology, were extensively tested. Useful AF PMSM parameters such as continuous torque and continuous current were measured. The winding temperature of the stators was also monitored and carefully examined. An attempt to assess motor performance, based on measurements and aimed at the identification of the weakest parts of the electric motor design is presented. In this paper it can be seen how the subcomponents of the machine and its detailed assembly process and tolerances play key roles in achievement of the designed continuous performance with symmetrical temperature distribution in the stator winding. Selected conclusions drawn from the obtained measurements were explained by a rotor/stator misalignment study using 3-D finite element analysis. [ABSTRACT FROM AUTHOR]