Design and optimization of a trapezoidal beam array energy harvester with operating wide speed rang for TPMS application

A tire pressure monitoring systems (TPMS) can effectively improve the safety traffic and air fuel efficiency. As a results, it is mandatory to install in automobile tires in some developed countries. So in recent years the vibration energy harvester (EH) applied to TPMS has increasing attention. One of major challenges of the harvester is to widen the operating speed rang of these harvesters which will determine whether the harvester can really be applied to TPMS. Base on that the large vibrations will be occurred when the tire is in contact with the road surface, a trapezoidal beam array EH which can operate in wide speed rang was proposed in this paper. In order to optimize the proposed harvester, a numerical analysis of the vibration characteristics of the tire was performed, and an optimization method called stress normalization method which is different from the traditional optimization method of EH is proposed, then the optimization of the EH was performed with ANSYS. The optimization results show that the average power output of the proposed EH is 42.0–437.2 μW at the rolling speed from 40 to 120 km/h, and electric energy output in one rolling cycle of the proposed harvester is 6.62–23.0 μJ at the rolling speed from 40 to 120 km/h, which can achieve TPMS power supply within a wide speed range.