Performance analysis of magnetic gear composite linear generator with single salient pole permanent magnet and integrated magnetic adjusting ring

Maritime wave energy movement is characterized by low operating speed and low frequency, which leads to problems such as large volume and weight, high cost, low power density, and large fluctuations of positioning force in a permanent magnet linear generator. In response to above issues, magnetic gear composite linear generator (MGCLG) for wave energy with single salient pole permanent magnet and integrated magnetic adjusting ring is proposed with high power density and low positioning force fluctuation. The working principle of the MGCLG is analyzed based on the magnetic field modulation principle of magnetic gears and the theory of permanent magnet generators; Then, the finite element method (FEM) is employed to simulate the performance of the MGCLG. Finally, a comparative analysis and verification of the performance between the proposed generator and the traditional generator is performed. It is shown that the amplitude of induced electromotive force in MGCLG has increased by 54.5%, and the fluctuation of positioning force has decreased by 51%. The novel MGCLG can greatly improve the induced electromotive force of the generator, and reduce positioning force fluctuations. The research provides insights for the development of new wave energy linear generator.