Enhanced electrical performance of spring-supported magneto piezoelectric harvester to achieve 60 Hz under AC magnetic field

Abstract Magneto piezoelectric harvesters (MPHs) operating under an AC magnetic field have attracted much attention due to their vital importance in portable industrial applications. Here, we present the first report of a spring-supported magneto piezoelectric harvester (SMPH) operating under an AC magnetic field to generate enhanced electric performance. As the length of the spring supporting the MPH becomes longer, the elasticity coefficient (N/mm) becomes lower and the resonance frequency decreases. In order to implement SMPH at a resonance frequency of 60 Hz, a spring with spring constant of 24.52 N/mm is used to support the MPH and produce maximum output power. To increase the output power of the SMPH, a magnetic tip was used to scavenge the AC magnetic field. The electrical performance of the SMPH with the magnetic tip mass showed an output voltage of 12.5 Vmax, output current of 654 μAmax, and output power of 5.56 mWmax at a load resistance of 30 kΩ and AC magnetic field of 80 μT. The SMPH exhibits an advantage over the conventional rigidly supported MPH with regards to output power. The demonstrated device is capable of meeting the requirements of charging and operating a wireless temperature sensor system, and thus it is most suitable for use in actual industrial sites where such magnetic fields exist.