A Hybrid Excitation Axial Flux Permanent Magnet Generator for Direct Drive Wave Energy Conversion

A novel hybrid excitation axial flux permanent magnet generation (HE-AFPMG) is proposed to improve the electromagnetic performance of conventional axial flux permanent magnet generation and suite the demands of direct drive wave energy conversion. Firstly, the configuration of the HE-AFPMG is introduced. Then operation principle based on open-circuit field distribution and qualitative analysis of field modulation are following. Finally, the electromagnetic performances under no-load and load conditions are analyzed. Meanwhile, the influence of the application of electric excitation on generator is also investigated. It verifies the validity of generator and confirms the excellent field-regulation capability. According to the results, it is proved that the addition of electric excitation field can not only reduce the harmonic component of back EMF, but also broaden the range of load torque.