Research on Power Control Strategy of Electromagnetic Energy Harvester Under Wide-Current Operating Conditions of Transmission Line

Abstract

Aiming at the energy supply problem of online equipment of transmission lines (TLs) under wide-current conditions (WCCs), the existing electromagnetic energy harvester (EMEH) has insufficient energy supply under low current conditions (LCCs) and is prone to sudden output power drop and abnormal operation status due to deep saturation of the core under high current conditions (HCCs). To this end, this article proposes a power control strategy based on EMEH under WCCs. Under LCCs, the load equivalent impedance is dynamically adjusted by the improved constant voltage method (ICVM) to improve the output power of EMEH. Under HCCs, the thyristor active bypass control strategy (TABCS) is adopted to suppress core saturation and achieve precise power output limitation. Theoretical and experimental synergy shows that under LCCs, the method proposed in this article can effectively improve the output power of EMEH, and the Maximum Power Point Tracking (MPPT) control strategy under 75-A bus current is 21.69% higher than that of direct power supply. Under HCCs, the control strategy proposed in this article can stably control the power output at the set value and prevent the saturation of the core.