Large power amplification of a piezoelectric energy harvester excited by random vibrations

This paper reports the method and results of amplifying the power output of a piezoelectric energy harvester excited by random vibrations. The amplification is achieved by applying a dual-mass-spring system. A maximum power amplification of 80 times has been experimentally demonstrated. The generated power output from a piezoelectric energy harvester, when excited by as-measured random vibrations, amounts to 28.9 μW. This is sufficient to operate a battery-free Tire Pressure Monitoring System (TPMS) for wireless sensing of pressure and temperature in car tires. Thus, the piezoelectric energy harvester with power amplification is proved to be a viable solution to replace batteries in the TPMS application.