High efficiency powering system for wireless sensor for AC monitoring in smart grid applications

A low maintenance and efficient powering system is being developed for applications in residential wireless AC line metering. A split core current transformer is used as the energy harvester. The collected energy is used to provide constant voltage output. The excess of the energy is stored in a backup battery or super capacitor hybrid. The smart charging approach is utilized to optimize charging/discharging rate in order to optimally utilize available power and maintain constant output voltage. The powering system is intended to operate with the power line average current 10..100 A_RMS and provide constant output voltage 3.3V and current up to 100 mA. The system is intended for use with wireless sensors in AC power monitoring applications. Current transformer coupling with the power line facilitates simple `snap-on´ installation of the sensors without interruption of power to customers.