Performance study of a piezoelectric-electromagnetic composite energy harvester based on a planetary acceleration mechanism

Traditional chemical batteries used in microelectronic devices suffer from low energy density, high maintenance cost and environmental pollution in long-term operation scenarios. This paper proposes a piezoelectric-electromagnetic composite energy harvester based on a planetary acceleration mechanism. The device innovatively integrates a planetary gear acceleration mechanism with a composite power generation unit to improve the piezoelectric-electromagnetic power generation performance by increasing the input speed. The electromechanical coupling model of the energy harvester is constructed. MATLAB simulation was used to analyse the influence laws of the planetary wheel, sun wheel and internal gear tooth ratios on the output voltage of the harvester, and the optimised planetary wheel parameter combinations were obtained to achieve a highly efficient and stable transmission. The influence of input speed and key system parameters on the collector output performance was further explored. Impedance matching experiments were conducted to maximise the power generation efficiency of the energy harvesting system. The results provide a theoretical basis and technical reference for the design and performance optimisation of rotating composite energy harvesters under complex working conditions.