Antisaturation and Power Decoupling Control of Multiwinding Energy Harvester Based on Magnetomotive Force Compensation

With the rapid development of smart grids, numerous monitoring sensors have been widely used for the state inspection of power lines. To ensure reliable operation of these sensors, the problem of their power source needs to be solved urgently. In particular, noninvasive inductive energy harvesters clamped over the lines are suitable as power sources for the monitoring sensors. This article presents the multiwinding energy harvester (MWEH), equipped with multiple energy output channels. To improve the antisaturation ability of the magnetic core and eliminate power cross effects between the windings simultaneously, an auxiliary winding is introduced to regulate the magnetomotive force. The method of maintaining the unsaturated working state of the magnetic core and the power decoupling control strategy between the windings are proposed. Hence, the global power fluctuation can be eliminated with a constant unsaturated state when the load and turns of any winding change. The experimental results suggest that regulating the energy harvesting factor of the auxiliary winding can desaturate the magnetic core. Furthermore, based on the linear operation of the MWEH, the problem of power linkage of the windings can also be solved, which stabilizes the output power of one or more windings.