In this paper, flux of permanent magnet tubular linear generator (PMTLG) is modeled and analyzed. With the model, air-gap leakage flux coefficient can be expressed analytically in terms of permanent magnet dimensions and air-gap width. The validity of analytical expression of air-gap leakage flux coefficient is verified by finite element analysis (FEA) with a maximum error of 6.8%. Furthermore, longitudinal end flux's influence 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 confirmed by FEA. Finally, after optimization of air-gap leakage flux coefficient and detent force, a PMTLG is built and experimented.
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