Fig. 2: Light adaptive power management system with a PV cell and electromagnetic harvesting.

a Schematic illustration of the circuit diagram of the adaptive power management (aPM) module, including PV harvesting unit, power switching module, and electromagnetic harvesting module, with associated conditions for changing the power source. b Four representative block diagrams of the aPM module show different connections of the power sources: PV cell, PV battery, and electromagnetic harvesting by adaptation to ambient light conditions.