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The development of measuring converters with a direct voltage-to-frequency conversion represents significant interest. This paper describes the possibility of using acoustoelectric effect for the development voltage-to-frequency converters. The first part of this paper deals with the theory of the acoustoelectric effect. In the second part the design and the realization of the voltage-to-frequency...
The article recommended the method of protection of power transformer from the influence of geomagnetically induced currents, by launching the resistive grounding mode at the period of geomagnetic disturbances and reversion to the solid-grounded mode on completing of geomagnetic disturbances. The article shows that for the identification of single-side saturation of the magnetic system of power transformer...
The article recommends the principle of commutative programming scan of the comparison signal. This principle allows linearization of transient characteristics «regulating pilot — output voltage» of pulse-width convertors. In the article obtained the expressions for determining the sequence of discrete samples, forming a functional scan reference signal. The functional scan is necessary for the linearization...
Determine complex conductivity of the microwave discharge plasma in resonator of the ion source. Using CST Microwave Studio allowed us to calculate dimensions of the resonance microwave window providing necessary reflection coefficient and to find effective amount of microwave discharge plasma from condition of resonance preservation. This makes it possible to determine value of electromagnetic filed...
Stationary magnetic field which necessary to electron cyclotron resonance formed by permanent magnets from alloy NeFeB. Computer simulation by code ANSYS allows us to find such configuration of permanent magnets that gives magnetic field strength equal 875 mT at input and output hole. Regulation of magnetic field distribution provides by special iron bars. Also, computer simulation shows that even...
The article describes the structural organization of the three-phase converter quickly reconfigurable networks constructed on the basis of autonomous voltage inverter with amplitude-width modulation. A multi-organization of power supplies at high and adjustable frequencies allows to operatively change operating modes of modules, adapting the network topology of the converter to the changing parameters...
Consider solution of equation, which describe motion of microwave discharge plasma components, and take into account microwave field, magnetic field of permanent magnets and elastic scattering on hydrogen atoms and ions. This solution has a resonant character, moreover, it shows that average energy of electrons in exact resonance on several orders greater than the energy corresponding to the maximum...
The paper considers the issues of burning metal jumpers on the surface of a semiconductor by current pulses of different shapes. Discovered that the passage of single rectangular current pulse with a duration of no more than 60 μs and an energy of 90 mJ observed the predominance of the processes of melting metal film over the contact melting at the interface. Current pulses of non-rectangular form...
In this article the questions of increase of reliability and durability, high-power pulsed microwave devices M-type. Analysis of the work metal-alloy cathode in the device showed its lack of resistance to a pulsed thermal loads caused by back electron bombardment. The developed design of metal-ceramic cathode unit with water cooling, able to withstand a pulse thermal load and divert from the cathode...
In the course of studies structural sensors for monitoring schemes cover mobile network operator's area are proposed. Three main types of sensors are developed, which are intended to be placed on transport and stationary. Sensors collect data about the state of the cellular network signal into the measurement location and shipment to Web-Server is made. The main transmission channels from the sensors...
The possibilities of modifying the IR spectra of porous silicon under irradiation by low doses of gamma — quanta of radioisotope source of 226Ra and bremsstrahlung radiation are investigated.
The article describes the results of a natural experiment to verify the mathematical model for calculating the ring magnet with a trapezoidal cross-section. Shows the graphical model of calculated the experimental magnet, as well as its real counterpart, with the measurement of the magnetic field in the center of which are compared of results of calculation of the mathematical model. Displays summary...
This paper devotes to the power quality increasing and electromagnetic compatibility ensuring problem in electrical networks of industrial enterprises with intensive application of nonlinear load, such as power converters of variable speed drive systems. The application of proposed hybrid active filter as a kind of effective decision for power quality increasing is presented in the paper. The proposed...
Application of new statistical methods for triangular sensor signal analysis is considered. The critical parameter here is the center of the laser beam. It is shown that the proposed method allows increasing accuracy of the sensors. Experimental verification has shown that the use of center of mass technique decreases root-mean-square error in 50%. While the proposed centralized integral steps method...
When choosing technological modes of diffusion welding of iron with metals it is necessary to consider that during heating of ferrite materials in a vacuum there is a possibility of changes in the structure and the main electromagnetic parameters of the ferrites. Given the large diversity of physical and chemical properties of the ferrite materials, it is necessary to assess the impact of vacuum-thermal...
Various technologies of all-optical switches are considered. In the course of the analysis it is concluded that all the existing technologies provide the highest performance electro-optic technology. New optical switching cell is proposed. It is different from the known cells that the selection of the desired output takes place without the involvement of an external control device. That why the switching...
The paper presents results of a study of commutation characteristics and triggering stability of small-sized vacuum switches with discharge gaps of about 1 mm. The experiments were carried out in microsecond range of pulse durations with current amplitudes from 50 A to 5 kA, and current rise rates of 109 … 1010 A/s. The upper limit of the commutated voltage range was limited by self-breakdown of the...
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