Low power implementation of maximum energy harvesting scheme for vibration-based electromagnetic microgenerators

Electromagnetic microgenerators are widely used as means for vibration-based energy harvesting. Just like other harvesting sources, they can also be operated to harvest maximum energy by controlling the resistance offered to the microgenerator. For low power, maximum energy harvesting scheme is quite difficult to implement due to the overhead power costs of the digital control circuits. In this work, a single stage AC-DC converter is utilized to boost the low voltage of the microgenerator. A novel maximum power tracking scheme is proposed which changes the duty cycle of the converter to offer optimum resistance to the microgenerator. The control system would only consume a few micro-watts of power and can be applied to low power systems. Relevant simulation and experimental results are provided to validate the proposed scheme.