Design and Experiment of a Permanent Magnet Tubular Linear Generator for Wave Energy Conversion System

In this paper, ∞ux of permanent magnet tubular linear generator (PMTLG) is modeled and analyzed. With the model, air-gap leakage ∞ux coe-cient can be expressed analytically in terms of permanent magnet dimensions and air-gap width. The validity of analytical expression of air-gap leakage ∞ux coe-cient is verifled by flnite element analysis (FEA) with a maximum error of 6.8%. Furthermore, longitudinal end ∞ux's in∞uence on the detent force of PMTLG is analyzed in detail with the model. A detent force minimization technique is deduced from the analysis results, and conflrmed by FEA. Finally, after optimization of air-gap leakage ∞ux coe-cient and detent force, a PMTLG is built and experimented.

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