Numerical analysis of a magnetic-spring-based piecewise nonlinear electromagnetic energy harvester

A magnetic-spring-based electromagnetic energy harvester (EMEH) with piecewise nonlinear stiffness is systematically analyzed in this paper. In terms of a traditional magnetic-spring-based EMEH, Ansys Maxwell is utilized to calculate the magnetic flux through the coil and the nonlinear magnetic force exerted on the moving magnet, based on which the influence of the position of the coil relative to the tube on the response characteristics is investigated. For the EMEH with the optimum position of coil, linear spring is introduced to the system to realize piecewise nonlinear stiffness, and the corresponding expression form of force is provided. Numerical simulations are carried out, and the influence of the impact position, excitation level, and linear spring stiffness on the output is investigated. The results demonstrate that the piecewise nonlinear stiffness in the magnetic-spring-based EMEH could enable the system to respond in a wider frequency range, thus generating more electrical energy.

Automated summary

This paper systematically analyzes a magnetic-spring-based electromagnetic energy harvester with piecewise nonlinear stiffness. By introducing a linear spring into the system, the piecewise nonlinear stiffness enables the system to respond in a wider frequency range, thus generating more electrical energy.