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A powerful pulsed dc converter has been developed for charging battery assemblies on board of hybrid and electric aircraft, which enables full battery capacity charging in cruise mode of the aircraft. This 10-kW modular design converter can operate in a buck–boost mode in a voltage range of 130–300 V with a current limit of 70 A at an output voltage of 150 V. The efficiency of the created converter is ~96–99%, depending on the power consumed in the load. The proposed modular design and multiphase control circuit can be used to create converters with different capacities and high efficiency.

The parameters of a number of high-voltage solid-state switches are studied. Based on the analysis of their work, a high-voltage pulse source with a size of 105 × 260 × 180 mm is assembled to supply cold plasma jets operating at the ac voltage of 220 V, 50 Hz.

A compact source of low-temperature plasma for biological and medical applications is proposed, which operates at kilohertz frequencies in the regime of flash-corona discharge with an energy of 0.1 mJ/pulse. The plasma source was tested in application to plasma pretreatment of green salad seeds. Plasma-treated seeds exhibited increased (by about 25%) germination speed as compared to that in the untreated control.

Barrier-discharge stimulation of chemical reactions has been studied in the case of methane oxidation by atmospheric oxygen with the formation of carbon monoxide and hydrogen. Experiments in a plasmachemical reactor demonstrated the possibility of increasing the yield of synthesis gas (syngas) by means of plasma pretreatment of the initial mixture of air and methane in a 7: 1 ratio at atmospheric pressure. The output-gas composition was determined by gas chromatography. It is established that the plasma-discharge treatment of the initial gas mixture leads to a 15% increase in the amount of syngas at the reactor output and increases the reaction selectivity with respect to hydrogen and carbon monoxide by 3.2 and 6.5%, respectively.

The degree of homogeneity of a diffuse dielectric barrier discharge in millimeter air gaps under atmospheric pressure has been analyzed. This analysis is based on the glow-brightness distribution in the discharge gap cross section with allowance for a cylindrical electrode shape. It is shown that the degree of discharge homogeneity depends on both the repetition frequency of voltage pulses applied to the discharge gap and the barrier material.

A homogeneous volume dielectric barrier discharge (DBD) in air at atmospheric pressure and natural humidity has been obtained. Conditions ensuring generation of a homogeneous DBD are described. It is shown that a determining influence on the homogeneity of DBD is produced by the rate of electric field strength growth in the discharge gap.

A complex of instruments implementing a new optical method of plasma diagnostics in electrophysical setups equipped with plasmatrons is described. The proposed method is based on the simultaneous monitoring of the intrinsic emission spectra and the images of plasma, followed by the joint analysis of these data. An analysis of the information gained using the new instrumentation complex provides a basis for the solution of various practical problems, including optimization of the working regimes of plasmachemical reactors and determination of the spatial arrangement of plasmatrons in newly designed systems.