REU Students Validate Energy Harvesting for a Prototyped Set of Self-Powered Sensors
Researchers at the Center for Compact and Efficient Fluid Power (CCEFP) at the University of Minnesota continue to set new benchmarks for the use of Hydraulic Pressure-Ripple Energy Harvester (HPEH) technology. The studies sponsored by the National Science Foundation’s (NSF) Engineering Research Center (ERC) program have resulted in several higher performing prototypes that demonstrate the viability as well as the power generation and power density gains possible using self-powered sensors.
The project has greatly benefited from student contributions within the Research Experience for Undergraduates (REU) program. REU students designed and tested every one of the nine prototype devices, representing six distinct generations of designs. All prototypes were developed with a flexible design enabling the use of combinations of commercially available piezoelectric elements, further permitting ease of configuration of the device for different target power demands. The project is driving the emergence of advanced HPEH powered devices capable of meeting a broad range of power demands, available energy densities, form factors, static pressures, and target applications.
Several of the prototypes developed by the CCEFP students advanced the potential of HPEH applications: Advancement in the energy harvesting circuit with inductance matched to the piezoelectric energy conversion element within an HPEH yielded a prototype with peak power output of 3.3milliwatts (mW). Another prototype was developed for compact, low-power sensing applications and achieved its required target output of 67microwatts (µW). The first HPEH-powered, wireless temperature sensor was demonstrated. And a single-crystal piezoelectric variant HPEH prototype yielded twice the power density compared to variants using co-fired multi-layer piezoelectric elements.