The new 42-V automotive electric system comes up with new requirements for alternator design. A three-phase permanent-magnet (PM) synchronous generator for automotive applications is designed using analytical algorithms. The electromagnetic (EM) field for a certain design is analyzed based on a proposed equivalent magnetic circuit model. The proposed model is validated by comparing the analysis results using the model and those based on finite-element analysis under no-load and full-load conditions for saturation considerations. The analysis results demonstrate the effectiveness of the proposed machine design methodology.