Stanimir Valtchev

Recent issues of global heating and energy shortages are imposing a need to change our paradigm around transportation. Somehow, electric vehicles are progressively standing as a strong and necessary alternative for the society. Technically and technologically the acceptance of the EV is easier now than ever but the psychology of the consumers and the running business of internal combustion vehicles, the whole existing infrastructure are too much conservative to be changed easily. The changes in technology require changes in the engineering society and its human resources. The objective of this paper is to give a contribution to the discussion and reflection of potential future scenarios where EV/HEV‘s are spread across the society. It gives an overview of the range of knowledge and competences necessary for a sustainable and streamlined development of those. In fact, it is expected that a new kind of professional profiles need to be created or developed to supply the work market with the right human resources. The paper provides some discussion on the creation of new profiles or adaption of existing ones. Among different possible scenarios the creation of post-graduation courses for students holding undergraduate profiles in the fields referred to earlier would be an interesting and viable solution for fast response. The post graduation would be focused in specific key areas of the EV/HEV. Several factors are pointed out to endorse this scenario

Currently, the energy supply for the portable and autonomous equipment comes almost exclusively from the battery. Unfortunately the maintenance of those sources of energy brings disadvantages due to the need for frequent recharging or replacement. In many cases the battery brings extra weight and volume to the electronic equipment, limiting its autonomy. Some possible alternative methods to replace the batteries as power source, or to achieve better maintenance of existing (or smaller) batteries, are the so called Energy Harvesting (EH) methods, i.e. to obtain energy from the environment. For the medical equipment, there is also a possibility to recover and store energy generated by the human body in its usual activities. To harvest energy from the human body or from the environment requires specific technology and materials. The electronic circuits must have extremely high efficiency both in energy conversion and energy consumption. Experiments were performed in order to calculate the power that could be generated from the chest during breathing, from the feet, during walking, etc. For the experiments, mostly piezoelectric effect was explored.

There have been many and very significant advances in the Wireless Power Transfer, resulting up to now in flexible and safe battery charging eliminating the necessity of power cables. The relatively low frequencies (tens of kilohertz) applied for those {"}classical{"} chargers are already well developed. A {"}new{"} technology appeared now that makes possible to apply a strong magnetic resonant coupling. Similar experiments were applied by N. Tesla more than a hundred years ago but now the researchers are capable to reach much higher frequencies. To achieve the necessary high level of magnetic field coupling it is essential to allow high levels of electric current intensity inside the resonant loops. In this article the achievement of highest magnetic field is analysed and experimented. Some results are discussed based on the choice of the resonant loop type and construction. The applications in the on-line energy supply for the EV are one of the aimed goals. The other goal may be the future more efficient induction machine.

The research on the solar concentrating equipment is intensified in the recent years in many scientific and industry groups and institutions. This growing interest is based mainly on the higher efficiency and lower investment in material that is typical for this solar technology. This work started not to answer a market problem but with the idea of development a new application for an domestic size collector of line-focussing Fresnel collector. Which is will be a important step for the renewable energy. If successful, in a few years a common person will be ready to produce solar thermoelectricity at home with the double benefit of producing electricity and hot steam. The paper presents a design methodology and heat transfer calculation for an concentrating system based on the Linear Fresnel Reflector (LFR) concept. The basic absorber design is an trapezoidal inverted air cavity without glass cover. The absorber is covered with a selective surface and is oriented north- south. This arrangement has shown good optical and thermal performance results validated by measurements during outdoor tests.

In the last time many research works were devoted to the electrical drive train with induction motors due to its robust construction and low cost in comparison with its competitor, PM synchronous motor. The construction of the induction motor is simple but its efficient control needs more sophisticated algorithms and appropriate inverters in order to obtain the highest technical and economical performance. In this paper we present a review of the last research results on the induction motor topologies dedicated to EV, on the architecture of inverters and of the efficient control strategies. There will be presented many promising solutions which are analysed and compared in order to offer to the EV electrical drive train designers the necessary information for a selection to be done.