励振型振動発電素子に適した高出力回路の検討

抄録

We designed a nonlinear circuit suited to the miniature autoparametric excitation harvester. The miniature autoparametric excitation harvester consists of the piezoelectric cantilever and the micro-patterned doubly-clamped beam formed by the photolithography followed by the wet-etching. The nonlinear circuit can decrease the acceleration threshold needed in the autoparametric excitation and the increased piezoelectric coupling force, combining the self-powered SECE (Synchronous Electric Charge Extraction) technique and the full wave voltage doubler rectifying circuit. Furthermore, compared with the parallel or series SSHI (Synchronized Switch Harvesting on Inductor) nonlinear circuit, the nonlinear circuit in this study showed less dependency on the resistive load, because of the SECE technique. The acceleration threshold is as low as 0.02 G, and we achieved the maximum output power of 1.2 mW at 0.3 G from the D cell size and 2 Hz frequency bandwidth.