Synchronized Switch Harvesting Technique Applied to Electromagnetic Vibrations Harvester

This paper presents the study of a new application of non linear techniques for energy harvesting. The Synchronous Electric Charge Extraction (SECE) harvesting technique for piezoelectric generators is extended and adapted to electromagnetic generators. Because of the magnetic flux/electrical charge duality, this new circuit is named SMFE for Synchronous Magnetic Flux Extraction. A global theoretical model is developed, and harvested power is simulated. Comparisons with a standard impedance matching extraction technique show that over twice the power can be harvested in a restricted area of the characteristic parameters. It also allows the maximum power to be harvested whatever the load value is, whereas impedance matching technique needs a constant tuning which is practically difficult to implement with a self supplied electronic. Finally, in order to confirm the theoretical results, the SMFE circuit was embedded and tested on a simple centimeter-scale electromagnetic harvester.