A Miniature Energy Harvesting Device for Wireless Sensors in Electric Power System

A novel energy harvesting device called the energy coupler is proposed which can provide power to small wireless sensors in a power system. The energy coupler when coupled electromagnetically to a nearby current carrying conductor scavenges ac power from the conductor. The proposed energy coupler converts the harvested ac power into dc using a passive voltage multiplier circuit. The design of the energy coupler is such that the dc power obtained is adequate to charge a miniature 1.2-V rechargeable battery. It is demonstrated that the energy coupler is capable of delivering 10 mW of dc power to a 50-Ω load. An analytical model is also presented which agrees well with measurement results within a margin of error of 10%.