|dc.description.abstract||This Thesis is organized in six Chapters according to the following order:
Chapter 1 deals with the General Approach of the Thesis, which describes its structure and a brief summary of each of the Chapters that comprise it, focusing on the main contributions. In addition, an analysis of the scientific contribution that has been produced with the completion of this Thesis is carried out.
Chapter 2, Objectives and Methodology, presents the individual objectives necessary to achieve the main objective of the thesis, present the experimental developments of hydrogen-based systems and examples of integration in land and air mobile platforms. According to the structure of the thesis, each of the scientific contributions included in Chapter 4, has the purpose of responding to each of the proposed objectives.
Finally, the work methodology used to achieve each and every one of the proposed objectives is presented.
In Chapter 3, Materials, the most important systems used for the development of this work are detailed.
Apart from the detailed description of the commercial test benches that have been used for the characterization of both batteries and fuel cells, it is worth highlighting the design and construction of the ground test platform and the total transformation of the aerial platform where they have been integrated electrical systems.
In Chapter 4, Results, the set of scientific contributions that support this thesis are presented. In this sense, three scientific articles published as first author in journals with a high impact index JCR are presented, as well as different contributions to international congresses, referents of the renewable energy and hydrogen sector.
In this context, article 1 studies the effect of a not much studied pollutant in low temperature solid polymer fuel cells and without cases found in the literature for high temperature. This pollutant is NH3.
Next, to demonstrate the application and advantages of hydrogen in electric propulsion systems, articles 2 and 3 present the design, development and implementation of different mobile aerial and land platforms.
The second article presents a real and practical case of transformation of a fixed-wing unmanned aerial system, used as an aerial target and powered by an internal combustion engine, into an electric RPAS. The main reason for carrying out this transformation is to increase the flight autonomy of the RPAS in order to be able to take measurements of the different parameters that affect large-scale crops. This purpose has been achieved by increasing autonomy by almost 50%.
On the other hand, this present work is an intermediate step to complete a hydrogen powered RPAS.
Finally, focused on land applications, article 3 aims to demonstrate a sustainable solution for urban mobility based on a one-person electric vehicle powered by hydrogen, which provides great advantages over the same battery-powered vehicle. To demonstrate this, both vehicles have been developed in comparable versions, using the same platform, seeking that the total weight of the one-person electric vehicle is the same in both cases. They have undergone experimental tests that support the characteristics of the hydrogen-based configuration versus the battery-based one, such as higher specific energy, more autonomy and shorter recharge time of the first.
In Chapter 5, General Conclusions, the most relevant conclusions obtained from this Thesis are discussed, and the lines of research that have been opened by the work developed are framed, in addition to proposing strategies and actions in this regard.
Finally, in Chapter 6, Other scientific contributions, a set of scientific contributions is presented in which the doctoral student has actively participated as a co-author during the completion of the doctoral thesis. This compendium of works includes a series of research articles published in journals with the high impact index JCR, as well as contributions to the main national and international conferences of the renewable energy and hydrogen sector. These contributions complement the research activity of the doctoral student, which is why they are included in the set of contributions that support this thesis.||es_ES