Self-Power Devices for A Wireless Sensor System Measuring the Shaft Alignment

In this work, we propose an energy harvester (EH) designed for wireless sensor system (WSS) applications on marine propulsion shafts. Two EH designs are presented: a flexible PCB-based EH and an EH with an integrated rotor and stator. The flexible PCB-based EH utilizes multiple magnets and flexible PCBs, achieving an average power of 2117.45 mW at a low speed of 100 rpm with a 3 mm air gap. This EH demonstrates that it is possible to implement a self-power WSS for real-time monitoring of a marine propulsion shaft. The second EH with a hollow circular tube, eight coils with 3,000 winding turns, and a 1.25T spherical magnet generates an average power of 303.21 mW at 100 rpm. The tube provides the fastest rolling of the magnet inside the tube which ultimately increases the electromotive force induced in the coils. This outstanding accomplishment demonstrates the potential of the proposed EH to create WSSs for marine shaft monitoring systems by collecting rotational energy during ship operations.