Flywheel proof mass transducer for energy harvesting applications

This paper introduces a new flywheel coil–magnet proof mass transducer for vibration energy harvesting. The seismic transducer presented in this paper includes an additional flywheel element that produces three effects on the elastically suspended proof mass: firstly, it lowers the fundamental resonance frequency, secondly it lowers the static displacement and thirdly it lowers the mechanical damping effect. The combination of all three effects is beneficial for vibration energy harvesting applications. In fact, having a low resonance frequency transducer facilitates the tuning of the harvester to a low frequency band where ambient vibration energy is normally higher. Also, having a low static displacement of the proof mass element allows the construction of a device robust to shocks and fast movements despite it has a low fundamental resonance frequency. Finally, having a low internal mechanical damping leaves more energy for the conversion to electrical energy. The paper presents both simulations and experimental results that contrast the principal electro-mechanical properties and the energy harvesting effects of classical and proposed flywheel coil–magnet proof mass transducers connected to a purely resistive load.