A Study on the Efficiency in the Energy Harvesting Device Using Resonance of Pendulum

Recently, increased public interest in pollution caused by fossil fuels has prompted studies on various renewable energy sources. As it is important to ensure power generation efficiency in energy harvesting, research in this area continues. Therefore, this paper presents the results of a numerical analysis to calculate the efficiency of an energy harvesting generator that uses pendulum resonance. The Lagrange equation was used to derive the numerical model of the pendulum, which in turn was used to derive the angle of power generation and time required to reach this angle. The power generation efficiency was derived by calculating the input and output work using the power generation angle and time obtained from the numerical model. In addition, the effect of design variables, such as the mass of the pendulum, the length of the pendulum, and angle at which power generation starts, on the efficiency is considered by presenting an efficiency map. The efficiency map presented in this study is expected to be an important reference for designing highly efficient energy harvesting devices using pendulum resonance