Output Characteristics of Passive Magnetic Energy Harvester Feeding a Constant-Voltage-Type Load

This article provides a methodology for deriving a family of output characteristics (dc-side I–V and P–V curves) for a passive magnetic energy harvester (MEH) clamped on a sinusoidal current-carrying conductor. It is demonstrated that MEH characteristics depend on primary current magnitude and frequency as well as on load voltage. First, expressions for power harvested by an MEH are derived employing a nonlinear B–H curve approximation of the core. Then, conversion losses are assessed to provide respective estimates for the power provided by the MEH to the load. Presented analytical findings are accurately supported by experimental results of MEH designed to harvest up to 240 W from a conductor carrying currents of up to 350 A.