SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 25357 papers
The paper examines methods for improving the visual detection of low-contrast, noisy image elements by emphasizing brightness transitions through decorrelation processing. It formulates contour extraction as a finite-difference operation on the video signal, analyzes its spectral representation and …
A compact single-channel analyzer for selecting pulses by amplitude or duration is described as a simpler alternative to versatile but bulky pulse-parameter analyzers. The instrument uses amplitude-time conversion followed by comparison of the converted pulse duration with stable reference pulses de…
This paper examines the synthesis and analysis of a two-dimensional coupled automatic control system for a distributed-parameter object whose direct channels are represented by second-order dynamics with phase lead. Using a matrix formulation, the authors derive closed-loop equations, discuss the di…
This paper studies intermittent excitation of a pulse power generator as a means of increasing pulse power while reducing no-load and thermal losses between stator-current pulses. Using a physical model, the authors derive transient expressions for excitation, damper currents, flux buildup, field su…
This paper examines stator winding heating and cooling in AO2 series induction motors under emergency conditions, especially locked-rotor three-phase short circuits and operation stopped on two phases. Using resistance measurements recorded continuously with an oscillograph, the authors experimental…
The article examines the technical and economic feasibility of replacing copper with aluminum windings in oil-immersed distribution transformers of sizes I and II. Using comparative calculations for 10 kV to 0.4 kV transformers and an optimization method based on minimum calculated manufacturing and…
This study examines how products formed by discharges in gas inclusions affect ionization aging and electrical strength in rubber insulation. Using model specimens with artificial inclusions, the work measures ionization intensity, surface resistance, and acidity during voltage exposure, and identif…
This paper examines defects in turn and ground insulation of random-wound stator windings in induction motors, with attention to failures during the run-in period. It proposes estimating insulation defectiveness from breakdown-voltage distribution laws rather than relying only on fixed-voltage break…
This paper examines the problem of sparking during commutation in direct-current machines, especially at the trailing edge of the brush under varying load. After reviewing earlier valve-based commutation circuits and identifying their limitations, the authors propose a valve-mechanical circuit using…
This paper develops a computational method for calculating the magnetic circuits of combined electrical machines with two rotating fields. It approximates steel magnetization curves by a hyperbolic sine relation and determines the coefficients by least squares solution of transcendental equations on…
The paper analyzes electromagnetic field distribution in the air gap of a flat linear induction machine with an open magnetic circuit, focusing on the case where the conducting channel is wider than the inductor and has electrically conducting walls. Under simplifying assumptions including infinite …
The paper addresses verification calculation of tolerances for the output parameters of asynchronous motors, including starting and maximum torque, starting current, efficiency, and power factor, as functions of manufacturing scatter in input parameters. It formulates tolerance propagation by both l…
This paper examines artificial delay lines whose delay time is varied smoothly by magnetic control of the inductance in each section. It develops a model for ferrite-core inductors with control windings, deriving exponential dependences of inductance, delay time, characteristic impedance, and output…
This paper examines artificial commutation as a means of improving the power factor of valve converters, focusing on a six-phase rectifier with an interphase reactor. It proposes a comparatively simple thyristor-based commutation unit using a commutating capacitor and controlled valves, and analyzes…
This paper examines phase-change amplifiers intended to improve the measurement of small phase shifts and small deviations from an average phase value. It develops a general model in which an electromagnetic energy storage element is charged or discharged while the charging-circuit parameters are sw…
This paper develops analytical tools for evaluating slip-ring induction motors operated with pulse speed control using semiconductor valve circuits. It represents the rotor phase current as the sum of an internal component and a pulsating component, applies Fourier analysis to obtain expressions for…
This paper examines circuit design options for exciting the cathode spot in excitrons intended for static converter drives of heavy machine tools. It compares a thyratron based ignition circuit, an electromagnetic circuit using a magnetic amplifier, and a proposed three phase contact circuit with lo…
This paper examines dynamic nonlinear structural constraints in MUS-D electric drives with intermediate semiconductor amplifiers and stabilizing correction circuits. Using transfer functions for the converter, motor, feedback, and correction elements, it analyzes the amplitude-phase frequency charac…
This paper examines how interference affects the static and dynamic behavior of MUS-D adjustable electric drives with a semiconductor preliminary amplification stage. Using production tests, laboratory investigation, input circuit analysis, and simplified nonlinear modeling of the PPU under saturati…
This paper examines stabilization of the MUS-D electric drive when positive current feedback is introduced into the comparison circuit of its automatic control system. Using transfer functions, Hurwitz conditions, and D-partition curves for several circuit variants, the authors analyze how adding a …
The paper compares structural variants for stabilizing deeply regulated MUS-D electric-drive systems with an intermediate semiconductor amplifier, focusing on how the coordinate used to obtain a correction signal affects delay sensitivity. Using transfer functions, D-partition analysis, and frequenc…
This paper analyzes the static speed error of MUS-D electric drives under several methods of introducing voltage and armature-current feedback, with attention to the requirements of machine-tool feed drives. Using block-diagram models and analytical expressions for error as a function of speed setti…
This paper presents a simplified engineering method for calculating heating and cooling processes in the windings of direct current electromagnets. Starting from the heat balance equation for an isothermal winding, the method linearizes the temperature dependence of winding resistance, copper heat c…
The paper addresses the calculation of dynamic transient processes in direct current electromagnets, focusing on time dependent current and armature motion, or velocity for a U shaped electromagnet with a transverse armature. It derives finite difference forms of the electrical and mechanical equati…
This paper addresses self-excitation and natural oscillations in a system consisting of a ferromagnetic frequency tripler, series-compensation capacitors, and an induction motor. The authors propose treating the motor supply circuit as a reactive electrical filter, deriving cutoff-frequency conditio…
This paper develops a calculation method for the external characteristic and steady-state short-circuit currents of a ferromagnetic frequency tripler, including cases with longitudinal capacitive compensation. Using a hyperbolic-sine approximation of the transformer steel magnetization curve, the au…
This paper presents a contactless temperature control system for salt bath furnaces intended to replace relay contactor circuits, whose drawbacks include contact wear, maintenance demands, switching disturbances, and possible process hazards. The proposed scheme uses a transformer regulated by magne…
This paper proposes a five-limb design for a transformer regulated by magnetic biasing of the shunt, addressing the problem of odd-harmonic electromotive forces induced in control windings and the resulting overvoltages. The design relocates the control windings to a separate central shunt limb and …
This paper addresses the notation used to decompose unbalanced multiphase electrical systems into symmetrical components, noting that conventional expanded equations become cumbersome and error prone when the number of phases is large. It introduces a compact indexed notation for phase vectors and c…
This paper addresses how an induction motor with an asymmetrical squirrel-cage rotor, a case arising from casting defects or broken bars, can be represented computationally by an equivalent motor with an asymmetrical wound rotor. Using symmetrical-component decomposition of the multiphase rotor curr…
This paper addresses automatic evaluation of casting defects in squirrel-cage rotors of induction motors, using the fluctuation of short-circuit current during slow rotor rotation as an indirect quality criterion. The authors relate the percentage current fluctuation to the percentage change in acti…
A method and apparatus are presented for detecting casting defects in squirrel-cage induction motor rotors before mechanical machining, when defective rotors can still be recast. The paper analyzes the operation of a differential inductor system in which rotor asymmetry caused by changes in bar resi…
This paper examines pulse excitation regulation for direct-current generators using thyristors with artificial commutation. It analyzes current buildup in the generator field winding under rectangular voltage pulses, assuming constant winding parameters, ideal shunting diode behavior, negligible sou…
This paper examines the selection of switching frequency in pulse excitation systems for electrical machines, where excitation current ripple produces additional losses and modulation of a direct-current generator output voltage. The authors derive relations for the excitation-current ripple factor …
This paper examines a relay pulse automatic position control system using a low power universal commutator motor with series excitation, motivated by the need for faster and simpler regulated electric drives. The authors describe the system structure, in which proportional control is corrected by an…
This paper examines the use of universal series-excitation commutator motors in low-power relay-type tracking electric drives supplied from an AC network. It argues that such motors can simplify converter circuitry, reduce the number of controlled relay elements, and improve acceleration because of …
This paper describes a pulse device for generating control voltages proportional to functions of three independent variables, specifically forms equivalent to multiplication with division and to a complementary ratio law. The proposed method uses a sawtooth voltage generator, pulse-width modulation,…
This paper develops an automatic control system for rheostatic and regenerative braking of a DC electric train with RT-113 traction motors. Using the maximum permissible interlamellar electromotive force as the commutation criterion, the authors derive a control law for excitation current as a funct…
The paper examines forced-commutation devices for thyristor pulse converters and addresses limitations of conventional circuits in which the commutating capacitor is prepared through the power thyristor. It proposes and analyzes two autonomous switching circuits for single-ended pulse-width modulati…
This paper describes functional elements for single-valve thyristor direct-current converters intended for regulated DC energy conversion. It presents forced-commutation circuits with resonant capacitor recharging and a discontinuous-current choke, showing how the arrangement can raise commutating v…
This article analyzes the static characteristics of a pulse-width modulated DC voltage converter with a smoothing filter, assuming operation from a source with zero internal resistance. Using pulse-system methods and approximate ripple calculations, it derives external characteristics for continuous…
This paper analyzes the onset of discontinuous current in pulse speed control of wound-rotor induction motors with a rectified rotor circuit and thyristor switching. Using a simplified steady-state equivalent circuit, it derives boundary equations for the transition between continuous and discontinu…
This paper examines pulse speed control for wound-rotor induction motors using thyristor switching in the rectified rotor circuit, either with additional rotor resistance or in cascade arrangements that return slip energy to the supply. It argues that varying the relative on-time of the power thyris…
The paper examines small-signal dynamics of valve electric drives supplied by fully controlled converters, focusing on nonlinear behavior in discontinuous-current regions. Under standard simplifying assumptions for motor parameters, valve drops, and supply stiffness, it linearizes averaged mechanica…
This paper analyzes discontinuous current regimes in fully controlled converters under decreasing load conditions. Using previously established notation and assumptions, it derives equations for cases in which the load current reaches zero during power valve operation or during the pause, including …
This paper develops a static analysis of single-cycle fully controlled valve converters operating in continuous current mode, including circuits with a neutral valve. Using a relative-unit formulation and assuming an ideal rigid supply, equal valve voltage drops, and constant load parameters, it der…
The paper examines local statistical indicators of forest stand destruction by a shock wave, focusing on whether the aerodynamic pressure inferred from directions of tree fall depends on tree diameter. It formulates a hypothesis that the distribution of fall directions for trees of a given diameter …
The paper discusses a problem posed by Ulam concerning the existence, for every measure zero set, of a countably additive measure defined at least on its Borel subsets, normalized on the set, zero on points, and compatible with restriction to nested subsets. It notes that when a subset of the unit i…
This note defines a density for parametrized oriented curves in a metric space using the asymptotic behavior of the maximal number of disjoint arcs of diameter at least a given scale. After formalizing components and points of a parametrized curve, it introduces a scale-ratio function and derives fr…
