A railway electromagnetic power generation system based on double-sided rack mechanism

Abstract The increasing demand for sustainable energy solutions necessitates replacing the traditional energy sources with renewable energy, particularly for realizing self-powered wireless sensor networks (WSNs) in railway transportation. This paper proposes a double-sided rack rail vibration energy harvesting system (DVHS) to harvest vibration energy generated by trains when they pass over the rail, providing electricity to the wireless sensor networks. The input mechanism, mechanical rectifier, power generation module, and adaptive interface circuit are designed for the proposed DVHS. The mechanical rectifier, composed of a double-sided rack and one-way bearing, is employed to change the railway vibration into rotation. Rotational energy is subsequently transmitted to the power generation module via a mechanical transmission device, converting the mechanical energy into electrical energy. Experimental results show that the DVHS generates an average power output of 854 mW with the vibration amplitude of 5 mm at 5 Hz. An adaptive interface circuit with the maximum energy conversion efficiency of 93.5 % is designed to efficiently extract energy from the vibration energy harvester and provide a stable output voltage. A 1.5 F supercapacitor can be fully charged by the DVHS within only 162 s, after which it powers the wireless sensing network for up to 300 s of continuous data transfer. The proposed DVHS presents a promising solution for sustainable condition monitoring in railway systems, reducing dependence on conventional power supplies.