An integrated self priming circuit with electret charge source

Abstract

Dielectric elastomer generators (DEG) are well suited to harvest energy from natural motion sources (e.g. water, human locomotion). DEG require a source of high voltage charge to generate energy. In low cost, low power DEG, a high voltage charge source is expensive and impractical to implement. The Self Priming Circuit (SPC) can be used to remove the high voltage charge source and replace it with a low voltage one. The SPC works by moving charge onto and off the DEG in synchrony with DEG compression to enable voltage boosting. For the initial cycle a low voltage source is still required in the form of a battery or similar device which in some instances can completely discharge, rendering the DEG useless. Another approach is to include an electret into the DEG design. The electret acts as a permanent voltage source for the DEG and SPC. This allows the DEG to receive a medium voltage (much higher than a battery) from the electret and then boost this voltage up to a high voltage where generation efficiency is improved. This paper presents an integrated SPC with an electret charge source that is capable of boosting quickly to a high voltage without the addition of external charge.