Thermoelectric-Generator-Based DC–DC Conversion Networks for Automotive Applications
Journal of Electronic Materials
As waste heat recovering techniques, especially thermoelectric generator (TEG) technologies, develop during recent years,its utilization in automotive industry is attempted from many aspects. Previous research shows that TEG as a waste heat harvesting method is feasible. Even though efficiencies for TEGs are as low as 3-5% with existing technology, useful electricity generation is possible due to the great amount of waste heat emitted from the internal combustion engine operation. This thesis
... oposes the innovative concept of thermoelectric-generator-based DC-DC conversion network. The proposed structure is a distributed multi-section multi-stage network. The target is to tackle problems facing the traditional single-stage system and to advance TEG application in automotive settings. The objectives of the project consists of providing optimal solution for the DC-DC converter utilized in the network, as well as developing a systematic and bottom-up design approach for the proposed network. Part I starts with a general overview of the waste heat recovering technology and its automotive applications. Following it is a brief description of recent automotive thermoelectric projects. Then, significant results of previous research which are related to this thesis project will be reviewed, leading to the purpose and target of this project. In order for a broader range of readers to understand the work presented in this report, the mechanism of TEG is briefly explained (in Chapter 2), together with the principle of DC-DC converters (in Chapter 3). In Part II, Chapter 4 analyzes the issue of impedance matching between TEG internal resistance and DC-DC converter input resistance. Theoretically-possible solutions for steady-state and dynamic matching are investigated regarding their feasibility. Then, Chapter 5 is dedicated to describe the development and evaluation of a MPPT Simulink/Simscape model targeting at achieving dynamic impedance matching. Part III first introduce the concept of the proposed TEG-based DC-DC converter network for automotive applications, and the topology of the proposed network is compared with that of the traditional single-stage topology. Then in Chapter 7, a design flow is suggested for the proposed network, with details of aspects in the flow analyzed. Most importantly, at the end of Chapter 7, a case study is presented, demonstrating the advantage of the proposed network over the traditional single-stage system. The result shows significant enhancement of system conversion efficiency. This report is concluded with Part IV, which is supposed to summarize major results achieved in this thesis work, and to give hints on possible tracks of future research.