Development and Analysis of a New Hybrid Excitation Brushless DC Generator With Flux Modulation Effect

A new hybrid excitation brushless dc generator (HEBLDCG) consisting of structure-parallel permanent magnet machine part and flux modulation machine part is proposed in this paper. Based on the flux modulation effect, the permanent magnet machine and flux modulation machine parts, which have different operating principles, can be combined. In addition, the proposed HEBLDCG features a lower short-circuit current by regulating field current, which increases reliability. The operating modes of flux modulation machine part are fully analyzed under different conditions. Changes in the phase shift factor of the permanent magnet machine part caused by the operating modes of the flux modulation machine part are investigated. Further, the proposed HEBLDCG features constant voltage output at a wide range of speeds. Finally, a prototype HEBLDCG is designed and manufactured. The experimental data agree with the simulated data. Loss breakdown is analyzed and efficiency is measured. An HEBLDCG with a reliable diode rectifier is promising for application in on-board dc power generation systems.