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This paper discusses the development of a new topology of cylindrical transverse flux linear machine for use with a free piston engine. Despite its three-dimensional flux path, the stator of this topology can be made from regular laminated components and only the translator includes soft magnetic composites. The design development is discussed, including alternative winding and fabrication techniques. Finite element analysis, results of a laboratory prototype, and numerical-reluctance analysis are all used to give insight into the machine characteristics. By using flux and flux linkage factors, the tradeoff between force requirement and power factor is explored. It is shown that the power factor of this topology will generally vary from 0.89 to 0.6, which compares well with other transverse flux machines. [ABSTRACT FROM AUTHOR]

In this paper, a new permanent magnet (PM) linear machine, termed the bipolar-flux (BF) doubly salient PM (DSPM) linear machine, is proposed and implemented. This BF-DSPM machine incorporates the stator-PM structure and the mover-PM structure into the DSPM machine topology. It consists of a mover with fault-tolerant teeth (FTT) and a stator with consequent poles. The FTT structure can provide the feature of phase-to-phase independence, thus offering the fault-tolerant capability. By using finite element analysis, the electromagnetic performances of the proposed machine are analyzed and then quantitatively compared with that of the flux-reversal PM machine, PM brushless DC (BLDC) machine and dual-PM machine. It confirms that the proposed machine can offer the advantages of high power density, high force density, and fault-tolerant capability. Experimental results are also given to verify the feasibility of the proposed machine. [ABSTRACT FROM AUTHOR]

In this paper, design and optimization of a ladder-type single-sided linear induction motor (Ladder SLIM) for machine tool applications is investigated. High-speed linear induction machines suffer from the end-effect phenomenon, which can reduce the thrust and result in declined output characteristics. Although it is common to consider this phenomenon in high-speed applications, it is essential to take it into account in the design and analysis of low-speed low-air-gap linear machines. In addition, Ladder SLIMs have significant flux density ripples, and using skewed bars for secondary of the machine is a common solution for it. Therefore, providing required equations, an algorithm for designing a Ladder SLIM considering the end-effect phenomenon based on Duncan model is proposed, and effect of several design parameters on the output characteristics are analyzed. In order to find the optimum design parameters, a multiobjective optimization problem considering efficiency, power factor, and braking force due to the end effect is defined. This problem is optimized with two algorithms, interior point and genetic algorithms, and results are compared. Finally, the validity of the obtained solution is verified using a 2-D and 3-D time-stepping finite-element method. [ABSTRACT FROM AUTHOR]

Design aspects of the trans-rotary magnetic gear (TROMAG) integrated rotary machine are discussed in this paper, with particular focus on optimizing system cost and weight. Analytical models are used for design of the TROMAG. Optimal designs of the rotary machine are found by using a population-based genetic algorithm and two-dimensional finite-element analysis and thermal considerations. Weight, volume, and cost of the resultant system are then compared with the Pareto-optimal set of a permanent magnet linear tubular machine that is designed for the same force and speed specification. It is shown in this paper that, for high-force low-speed reciprocating motion applications, an electromechanical motion system consisting of a TROMAG and a rotary electric machine can far surpass a conventional direct drive linear machine in terms of weight, volume, and initial and operating cost. [ABSTRACT FROM AUTHOR]

A novel double-sided electric asymmetric linear switched reluctance motor (LSRM) is proposed in this paper. The features of the proposed linear machine are that mover teeth and stators are not exactly identical according to the axis of the moving platform. This machine structure ensures that the alleviation of motor saturation magnetization effect and a higher thrust force output can be derived from the asymmetric LSRM. A thorough magnetic analysis is carried out for performance prediction of the machine, and results are compared to a symmetric LSRM counterpart. Both theoretical and finite-element methods results prove the priority of the asymmetric LSRM with higher force-to-volume ratio and better acceleration performance. Experimental results from the machine prototype validate the design of an asymmetric LSRM with yoke length of 12 mm. [ABSTRACT FROM PUBLISHER]