Design of Mechanical Frequency Regulator for Predictable Uniform Power from Triboelectric Nanogenerators

Mechanical energy scavengers convert irregular input mechanical energy into irregular electrical output. There is a need to enable uniform and predictable electric output from energy scavengers regardless of the variability in the mechanical input. So, in this work, a mechanical frequency regulator is proposed that fixes the input forces and input frequency acting on a triboelectric nanogenerator, thus enabling predictable electric output. The irregular low frequency mechanical input energy is first stored in a spiral spring following which the energy is released at the desired frequency by means of an appropriate design of gear train, cam, and flywheel. By regulating the nanogenerator output at 50 Hz, a standard power transformer can be optimally driven to increase the output current to 6.5 mA and reduce its voltage to 17 V. This output is highly compatible for powering wireless node sensors as is demonstrated in this work.