A Dual-Mode Saturable Core CTEH With Intermittent Operation for Autonomous Sensors: Robust Power Harvesting Across the Full Current Range

The deployment of autonomous sensor nodes in industrial environments, such as power grids, is critically limited by the need for a reliable and maintenance-free power source. This paper addresses this challenge by developing a comprehensive Current Transformer Energy Harvester (CTEH) system capable of providing robust, self-sufficient power across the full scale of line currents. The harvester’s robustness against high-current surges is achieved through an inherent self-regulating Voltage Transformer (VT) mode, which complements the standard Current Transformer (CT) mode. Furthermore, to overcome the critical challenge of powering sensors under low-current conditions, a novel intermittent operation strategy is introduced and experimentally validated. This strategy allows the system to reliably power sensor-like constant power loads even under low line current conditions. The combination of this dual-mode principle and the intermittent power management strategy provides a practical solution, paving the way for the development of autonomous online monitoring sensors.