A portable renewable wind energy harvesting system integrated S-rotor and H-rotor for self-powered applications in high-speed railway tunnels

[Display omitted] •A portable wind energy harvesting system is designed for self-powered applications in a high-speed railway tunnel.•The H-rotor and S-rotor are integrated to harvest energy from the natural wind and the piston effect in the tunnel.•The electrical energy was stored in supercapacitors to power the monitoring sensors of the high-speed railway tunnel.•Wind tunnel tests showed an efficiency of up to 23.2%, which indicates an opportunity for self-powered applications. The operation safety of high-speed railways has received great concern globally in recent years. The power supply of the electronic monitoring devices alongside high-speed railway tunnels and their maintenance are becoming increasingly important. In this paper, a portable renewable wind energy harvesting system integrated with an S-rotor and H-rotor has been designed to provide electricity to the monitoring sensors alongside railway tunnels in remote areas with shortages in the electricity supply. The proposed renewable wind energy harvesting system can harvest the wind energy inside the tunnel and convert it into electricity for self-powered applications. The renewable wind energy harvesting system scheme mainly consists of three components: a portable wind harvester mechanism, a generator module and a power storage module. The S-rotor and H-rotor are integrated as the wind harvester mechanisms in this system. The S-rotor harvests natural wind energy, and the H-rotor harvests piston wind energy when a high-speed train passes through the tunnel. Meanwhile, the S-rotor and H-rotor rotate the generator module separately through the one-way bearing. Finally, the supercapacitors in the power storage module are used to store the electrical energy. Experiments were conducted to study the performance of the system. A maximum electrical power output of 107.76 mW and a maximum efficiency of 23.2% are demonstrated in the test. The experimental data indicate that the wind energy harvesting system is beneficial and is a promising method to generate energy used for renewable self-powered applications in high-speed railway tunnels.