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This paper presents a model of the typical dielectric barrier plasma discharge at atmospheric pressure, structured as an equivalent electric circuit whose elements are identified with, and deducted from, the main influential variables of the process, namely, the applied gas, the geometry of the reactor, the breakdown parameters, as well as the power supply associated to the dielectric barrier discharge cell. Considering a parallel-plate reactor and a high-voltage sinusoidal power supply, an electrical comprehensive Simulink/MATLAB model has been developed in order to reveal the interaction between these two elements. The main components of this discharge model are as follows: 1) a double dielectric capacitance; 2) a voltage-controlled current source; and 3) a gas capacitance associated to the ionized gas. A sinusoidal voltage of up to 15 kV peak to peak at frequencies of 12.5 and 47 kHz has been applied to the discharge electrodes. The electrical model is based on the power law proposed by Roth, which defines the V-I behavior during the discharge startup. A series of simulations has been carried out in order to estimate the total current and voltage consumed during each discharge and to identify those parameters which are not measurable during the process. Finally, both the experimental and simulated voltage and current results in helium, argon, and nitrogen, as well as their Q-V graphics, are shown, and a comparison between them is discussed. Index Terms--Dielectric barrier discharge (DBD), voltage-controlled current source, voltage source inverter (VSI).

Objective: an innovative non−thermal plasma (NTP) system constituted by a radiofrequency (RF) power generator directly coupled to a treatment probe is described and characterized. This system is intended to be applied as a medical device for therapeutic treatments. Methods: electrical characterization of the radiofrequency power generator supplying the treatment probe was performed. Meanwhile, generated NTP was optically analyzed. Obtained data were studied to establish the safety profile of plasma application on heat sensitive matter. Results: the NTP system was validated through bacterial deactivation trials, as well as, of being capable of deactivating carcinogenic cells. Besides promoting and accelerating wound closure in vivo performed in mice, demonstrating faster healing than that done with conventional treatments. Conclusion: the NTP system's characterization is an essential stage to determine the adequate application of the generated plasma over organic media. The therapeutic benefits of the NTP system were proved by the development of in vivo experiences involving laboratory mice. Significance: the generated NTP interacts with surrounding air particles producing reactive oxygen and nitrogen species, which, exhibit bactericidal and antiseptic effects due to their strong biochemical reactivity; functioning like critical mediators in animal physiology and promoting wound healing processes. These properties make the NTP system a feasible technology intended for therapeutic treatments. [ABSTRACT FROM AUTHOR]

In this article, a novel class-E amplifier topology, based on the functioning principle of the stacked converters, is presented. In this amplifier the available output electric power is determined by the addition of the electric power generated by each of the associated devices. Herein, two MOSFETs connected in series are linked, on the one hand, to a dc voltage source and, on the other hand, to a resonant LC circuit and a resistance charge connected in parallel to the capacitor. Both MOSFETs are driven by a gate-to-source square signal allowing a synchronized commutation, promoting a quasi-resonant amplifier behavior similar to that of the classical class-E amplifier; with the characteristic of being able to manage the double of applied dc voltage amplitude and to supply twice electric power to the same load in comparison with the class-E amplifier. This device is able to distribute the same electric power between both MOSFETs, reducing at almost half the magnitude of applied drain-to-source voltage. As a result, voltage stress of each power switch is reduced in comparison with the typical class-E amplifier. Drain efficiency (DE), power added efficiency, and gain of the proposed device were obtained in function of the applied dc voltage. [ABSTRACT FROM AUTHOR]