With the aim of providing a power supply for the study of dielectric barrier discharge (DBD) excimer lamps (excilamps), a current-mode converter that allows for an accurate adjustment of the electrical power injected into one of those lamps is designed and implemented. Starting from the electrical model of the DBD lamps, the convenience of using a current-mode supply to control the lamp power is demonstrated. With the proposed converter, the current supplied to the lamp has a trapezoidal almost-square shape controlled by means of three parameters, namely, amplitude, duty cycle, and frequency, which provides full control of the lamp electrical power. Implementation is made considering a step-up transformer interfacing the high-voltage lamp with the converter. Experiments demonstrate the operating principle of this converter, including ultraviolet power measurements for a DBD XeCl excilamp. The capabilities of the converter are used to analyze the lamp behavior under different combinations of these three parameters, illustrating its capabilities for finding the optimal operating point of a DBD reactor.Index Terms-Current control, dielectric, dielectric barrier discharge (DBD), excimer lamp (excilamp), ultraviolet (UV).

In Dielectric Barrier Discharges (DBDs), the control of the power transfer, from the low-voltage static converter to the high voltage DBD, is strongly affected by the parasitic capacitive effects of the step-up transformer. Minimizing these capacitances is of major importance and this paper aims to establish and validate analytical expressions in order to predict the values of the parasitic capacitances of high ratio, step-up transformers, according to different windings arrangements using cylindrical conductors. Afterward, experimental validations are performed on three transformers which have been realized according to same specifications, in order to show the accuracy of the method and to understand the influence the winding arrangements on the capacitive parasitic effects.

This paper presents the study of a series-resonant inverter for the supply of a dielectric barrier discharge excimer lamp. Causal analysis, based on the fundamental properties of the load, is used to detail the reasoning which has led to this topology. In order to effectively control the lamp power, the operating mode of this converter combines discontinuous current mode and soft commutation (zero-current switching), obtaining low electromagnetic emissions and reduced switching losses as well. The model of the lamp is briefly presented, and it allows a simple state plane analysis to calculate all the electric variables involved in the converter and, consequently, to select the components of the supply. The mathematical relationships obtained from this process, for injected power control by means of the available degrees of freedom, are validated with simulations and experimental results. Index Terms-Dielectric barrier discharge (DBD), gas discharge devices, plasma sources, resonant inverter, ultraviolet (UV) sources, zero-current switching (ZCS).

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This document reviews the current-mode supply approach for dielectric barrier discharge (DBD) excilamps. It briefly demonstrates why this mode assures the control of the power injected into the DBD. Considerations with the step-up transformer required for the correct operation of the currentmode are developed. This document shows and compares four different converter topologies that comply with this principle. This comparison is made in terms of electric efficiency and luminous efficacy using experimental measurements.

The lack of sustainable solutions to mobility and transportation is a major problem in Latin American cities and requires prompt solutions. The main issues in Latin America are the high-cost of solutions, no inclusion of renewable energies, poor energy management, the use of foreign systems not adapted to local contexts, ineffective regional legislation and politics, among others. In this paper the main technical issues concerning the implementation of a bike-sharing system using pedaling-assisted (PAS) electric bicycles for Bogota City are discussed and a solution is proposed. To solve such problems, a methodology to design a tailored solution well suited to Bogota citizen’s needs is developed. Such methodology starts with the development of an on-board-computer (OBC) in order to characterize bike-users by collecting a rider’s data in real-time. Furthermore, the proposed solution develops a low-cost middle-drive (mid-drive) propulsion system for the PAS in the electric bike using brushless-DC (BLDC) motors and by implementing a field-oriented controller (FOC). The reported bike-sharing system also includes the development and implementation of two charging-stations that enable charging the battery on the electric bikes exclusively by using photovoltaic energy. Experimental results are presented and discussed.

OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. Abstract-Three different electrical generators have been designed and used to supply an exciplex dielectric barrier discharge lamp in order to elucidate the influence of each one of these supplying strategies over the system performance; the first method consists on supplying the lamp with short bipolar voltage pulses; the second and third methods are based on semiresonant converters were current pulses, of controlled duration and magnitude, are injected into the lamp. For each one of the generators, measurements of the lamp and supply efficiency, are performed and analyzed, at different levels of power (up to 130 W) and operating frequencies (60-90 kHz). From the experimental results, the pulsed voltage-mode approach has allowed obtaining the highest lamp efficiency (7%), yet the maximum supply efficiency is offered by the resonant mode supplies. On the basis of the lamp and the supply efficiencies, the whole system performance is analyzed.Index Terms-Dielectric-barrier discharge (DBD), exciplex lamp, pulsed voltage, resonant converter, ultraviolet.

Friction is an inherent factor in any real physical system, affecting, as it is natural, the dynamics of the entire system. In particular, the computation of friction losses are of special interest because friction factors can not be easily predicted theoretically in an accurate manner. In oscillatory systems friction is studied by two approaches, viscous and dry damping. Viscous damping is usually treated in physics courses due to its relatively easy-to-find analytical solution, whereas dry damping requires piece-wise solutions. This paper studies friction factors affecting a customised experimental platform for electric bikes. We seek to estimate the friction torque and then the coefficient of friction, where the damping of its amplitude will be evaluated. We study the oscillations of two different rolling systems. The first rolling system is a rowlock, and the second is a bicycle wheel axis. In both systems amplitude damping was measured and analysed. The experimental data for each rolling system was obtained by visual information, recording oscillations using a smartphone camera and then analysing it using Tracker, a freeware for video analysis. Results show that both systems behave very close to a dry damped oscillation. The model proposed matches properly the experimental data, and a value for the friction torque and coefficient of friction in both systems was estimated.