Modeling, analysis of, and experimentation on an energy harvester device for tire pressure monitoring systems

Tire pressure monitoring system (TPMS) is a system designed to monitor the air pressure inside vehicle tires and to provide an early warning system in case of low or high tire pressure. This technology is mandatory in many developed countries, as part of a global effort for increasing energy usage efficiency. A standard TPMS device runs on batteries and thus there are issues regarding maintenance and disposal of these devices. Replacement of batteries increases the operational costs as well as resulting in a significant amount of pollution. A batteryless TPMS eliminates this problem. There is significant amount of research efforts on this topic and it is increasing. In this thesis a novel, patent-pending design is modeled and simulated in a numerical software platform. The modeling includes collision modeling, dynamic equations of coupled electro-mechanical systems, and investigation of contact problems. For verification of the model a prototype is designed and constructed. Numerous experiments are conducted on the prototype. The prototype is tested at low speeds and the numerical model is verified using the data gathered from the experiment and the numerical simulations. In both numerical and experimental cases, the maximum power output was obtained when the load resistance matched the generator internal resistance, a well-known fact. The numerical simulation is used to obtain power output of the system for vehicle speeds up to 150 km/h. It is seen that even at speeds as low as 20 km/h the harvester generated 2.2 mW of average power which is enough to energize a TPMS device