Increasing Electrical Damping in Energy-Harnessing Transducers

Wireless microsensors that monitor and detect activity in factories, farms, military camps, vehicles, hospitals, and the human body can save money, energy, and lives. Miniaturized batteries, unfortunately, easily exhaust, which limit deployment to few niche markets. Luckily, harnessing ambient energy offers hope. The challenge is tiny transducers convert only a small fraction of the energy available into the electrical domain, and the microelectronics that transfer and condition power dissipate some of that energy, further reducing the budget on which microsystems rely to operate. Improving transducers and trimming power losses in the system to increase output power is therefore of paramount importance. Increasing the electrical damping force against which transducers work also deserves attention because output power is, fundamentally, the result of damping. This paper explores how investing energy to increase electrical damping can boost output power in electromagnetic, electrostatic, and piezoelectric transducers.