In-Tire Electromechanical Energy Harvesting System Design,Simulation And Verification

With the development of intelligent tires,real-time data transmitted by the in-tire sensors is critical to the vehicle safety and performance.The traditional battery power supply method of in-tire sensors couldn't meet the requirements of data transmission frequency and power supply.Recent researches propose in-tire energy harvesters based on principle of piezoelectric,electromagnetic and electrostatic mechanism,however,most of them can only provide power of ?W level.This paper designs a high-power density in-tire energy harvester for the power supply of tire sensors,utilizing rack-pinion mechanism to convert the mechanical energy into electricity from the periodic tire deformation when contacting the earth.The proposed in-tire energy harvester aims at generating power of mW level and providing continuous electricity for in-tire sensors system.Especially,rack and pinion,one-way clutch,flywheel and micro-generator are used to ensure the consistence of the device performance.The proposed energy harvester is amounted radially between the hub and tire inner liner.Principle description,simulation analysis,parameters optimization,device prototyping and lab tests are carried out to characterize and test the performance of the proposed energy harvester.The experimental results and the simulation results of the energy harvester show similar characteristics.The higher the vehicle speed and the wheel load are,the higher voltage and power can be generated by the proposed energy harvesting device.The generated power shows periodicity,the one-way clutch and flywheel ensure the unidirectional and stable output performance of the device.The experimental results show that at vehicle speed of 57km/h,the peak voltages of the 36? load is 2.20 V and the average power can reach 82 mW,even at low vehicle speed like 10km/h,the proposed device can reach average power of 6mW.After test verification,the proposed in-tire energy harvester can provide power of mW level,enough to meet the power supply requirements of intelligent tire sensors system.