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Recently, linear generators have been widely employed to convert oceanic wave energy into electricity. Among various linear generators, linear permanent magnet generators (LPMGs) have gained attention due to their special characteristics such as high power density and simple control structure. In this paper, flat double‐sided LPMG is investigated and designed. Considering all effective design variables, a particle swarm optimization algorithm‐based optimization method is employed to maximize efficiency and minimize weight. The optimization results show an increase in efficiency and a reduction in the weight of the generator. Finally, the design results are evaluated and validated using magnetic equivalent circuit and finite element analysis methods. [ABSTRACT FROM AUTHOR]

Abstract: Linear induction motors have been widely employed in industry because of their simple structure and low construction cost. However, they suffer from low efficiency and power factor. In addition, existence of so called end effect influences their performance especially in high speeds. The end effect deteriorates the performance of the motor by producing braking force. So, in this paper, by using Duncan equivalent circuit model, a new analytical equation is proposed to model end effect braking force. Employing the proposed equation and considering all phenomena involved in the single-sided linear induction motor, a simple design procedure is presented and the effect of different design variables on the performance of the motor is analyzed. A multi-objective optimization method based on genetic algorithm is introduced to maximize efficiency and power factor, as well as to minimize the end effect braking force, simultaneously. Finally, to validate the optimization results, 2D finite element method is employed. [Copyright &y& Elsevier]

Single-sided linear induction motors (SLIMs) have been widely used in industry, especially in high-speed transportation systems. The performance of the SLIMs is considerably affected by the characteristics of its secondary back-iron. The conductivity of the iron used as well as its magnetic permeability influence the performance of the machine, while the magnetic permeability itself is affected by the input frequency of the SLIM. In this paper, using Dancan equivalent circuit model and considering all phenomena involved in the single-sided linear induction motor, the outputs of the motor such as efficiency, power factor, normal force and output thrust are analytically derived. Then, the effects of the input frequency on depth of the field penetr-ation and saturation level of the secondary back-iron as well as the SLIM outputs are analyzed. To confirm the analytical results, 2D time-stepping finite element method is employed. The results are in good agreement with each other confirming the analytical analysis. [ABSTRACT FROM AUTHOR]