A dynamic regulating mechanism for increased airflow speed range in micro piezoelectric turbines

摘要

© 2016 IEEE.The paper reports the design and fabrication of a micro-planar spring for a dynamic regulating mechanism to decrease the cut-in (start-up) airflow speed of a piezoelectric turbine. This mechanism is implemented by adjusting the magnetic coupling between the turbine rotor and a piezoelectric cantilever using the spring. Varied spring shapes and dimensions were analyzed with the finite element method (FEM) to optimize the structure. A micro spring with an ultra-low spring constant of 0.78 N/m was fabricated from titanium foil by laser machining. The spring was installed into a miniaturized air turbine to achieve the self-regulation. The cut-in speed was 2.34 m/s, showing a 30% improvement against a non-regulated turbine.