Design and Optimization of the Energy Harvesting Device for Wireless Sensors

With the swift advancement of Smart Grid and the great expansion of urban distribution networks, condition monitoring sensors have emerged as a potential solution to enhance the efficiency and effectiveness of power supply. Meanwhile sensor nodes utilized in condition monitoring systems are often powered by either batteries or line power. However battery-powered sensors could suffer from a limited energy supply and require replacement upon depletion, leading to raising the cost of maintenance. This paper introduces a novel approach to circumvent the aforementioned limitations by proposing the utilization of energy harvesting from the magnetic field surrounding electrical power lines. The energy harvesting apparatus consist of three primary components, namely energy-taking coils, rectifier and filter circuit, and DC load. Meanwhile this paper describes a proposed optimal design of the core for magnetic energy harvester and evaluates the essential dimensional parameters, including the outer diameter to inner radius distance, core length, and number of winding turns, that significantly influence the coil terminal’s induced voltage. Furthermore, the output power of the proposed energy harvester under the condition of 300A current applied to the cable and 600 coil turns is up to S.16 $\mu$W, which surpass the power consumption of most sensors. These findings demonstrate the efficacy of the proposed energy harvester in extracting energy from the surrounding magnetic fields of three-core cables, and confirm that its output power can meet the requirements of wireless sensors.