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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]

This paper develops a new model with adjustable accuracy to evaluate performance of permanent magnet Vernier machine (PMVM) based on flexible magnetic equivalent circuit (MEC) method. The desired machine parameters such as number of flux modulation poles (FMPs), winding pole‐pairs, and geometrical dimensions can be chosen in the presented model. By utilizing nonlinear core magnetization curve, saturation effect is taken into account. There are two main contributions in this study. First, the flexible MEC model is developed to predict the machine performance accurately. The second contribution is that the developed model can be used to evaluate the performance of the machine under no‐load and loading conditions at the same time. The results of MEC model under no‐load and loading conditions are compared with 2D‐finite element method (FEM) and 3D‐FEM in terms of accuracy and simulation time. The results indicate acceptable accuracy and suitable processing time of the proposed MEC model. [ABSTRACT FROM AUTHOR]

Minimizing the material usage in thin‐film solar cells can reduce manufacturing costs and enable mechanically flexible implementations, but concomitantly diminishes optical absorption. Coherent optical effects can help alleviate this inevitable drawback at discrete frequencies. For example, coherent perfect absorption guarantees that light is fully absorbed in a thin layer regardless of material or thickness—but only on resonance. Here, it is shown that "omni‐resonance" delivers such coherent enhancement over a broad bandwidth by structuring the optical field to nullify the angular dispersion intrinsic to resonant structures. After embedding an amorphous‐silicon thin‐film photovoltaic cell in a planar cavity, pre‐conditioning the incident light using an alignment‐free optical arrangement severs the link between the resonant bandwidth and the cavity‐photon lifetime, thereby rendering the cavity omni‐resonant. Coherently enhanced near‐infrared absorption doubles the photocurrent over the targeted spectral range 660–740 nm where every wavelength resonates. These results may pave the way to transparent solar cells that optimally harvest near‐infrared light. [ABSTRACT FROM AUTHOR]