Modeling and Performance Analysis of a Narrow-Gap Magnetostrictive Vibration Generator Based on an Equivalent Magnetic Circuit

Abstract In this study, MATLAB Simulink magnetic circuit simulation models were developed for conventional and narrow air-gap-type magnetostrictive vibration generators based on the equivalent magnetic circuit method. A simulation model was developed using finite element stress analysis to determine the relationship between the vibration displacement of the generator and stress of the Fe–Ga alloy. The relationship between the reluctance, stress, and magnetic flux density of the Fe–Ga alloy was expressed using a look-up table module. The magnetic circuit distribution of the generator and the magnetic flux in each circuit were determined using finite element static magnetic field analysis, and the leakage reluctance was derived. The variation in the air-gap reluctance with vibration displacement was mathematically modeled. Through vibration experiments and dynamic simulations of the magnetic circuits, the variations in the magnetic flux density within the coils and open-circuit voltages of the two generators at the same frequency and vibration displacement were compared. The output performance of the two generators and the accuracy of the MATLAB Simulink magnetic circuit simulation models were verified.