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 manufacturing accuracy in TVF-100 turbogenerator stator bars with Monolit-2 insulation, focusing on how dimensional scatter affects winding reliability, calibration, and additional insulation requirements. Using statistical measurements of bar width and height at successive produc…
This paper examines heating in the end parts of a turbogenerator rotor under abnormal operating conditions and evaluates a copper segment damper system intended to divert induced transverse currents. A reconstructed 750 kW turbogenerator rotor was instrumented with thermocouples and tested in asynch…
This paper reports comparative tests of a 500 kW, 6 kV squirrel-cage induction motor with conventional compounded mica-tape insulation and an otherwise similar motor using Monolit-II thermosetting epoxy glass-mica insulation. Electrical, thermal, and reliability tests were used to assess dielectric …
The paper addresses the estimation of copper temperature distribution in electrical machine windings when cooling is nonuniform along the turn length, a situation in which average resistance measurements may obscure local overheating. It formulates a one-dimensional heat conduction model with axial …
This paper describes a two-stack generator with combined excitation, intended for regulated autonomous power supplies where different loads may require different voltages, frequencies, phase numbers, or waveforms. The authors present the magnetic arrangement of a machine using permanent magnets and …
This paper analyzes the energy characteristics of brushless DC motors with sinusoidal phase EMF under neutral commutation, focusing on how mismatch between current and EMF waveforms affects efficiency and machine utilization. Using previously derived torque and power relations, the authors obtain ge…
This paper develops torque and power equations for brushless DC motors supplied by semiconductor commutators when the excitation field and phase voltages contain nonsinusoidal harmonics. Using the general theory of electrical machines, it represents phase voltages, currents, and flux linkages as har…
This paper examines how to calculate the operating electric field strength in the working gap of multipole synchronous unipolar capacitive generators with grounded electrode systems. Using oscillographic measurements of output voltage for different active-load modes, rotor-position synchronization, …
The paper examines compensation methods for measuring the form factor of alternating current and voltage waveforms, motivated by the need to assess the effects of higher load-current harmonics on electrical machines and devices. It analyzes several circuit arrangements based on null comparison of rm…
This paper examines how distortions in the waveform of load current affect the output voltage of alternating-current sources, especially generators operating with nonlinear inductive-active or unbalanced loads. It argues that the commonly used nonlinear-distortion factor is insufficient because it d…
This paper compares capacitor-bank and rotating-generator power supply schemes for the electromagnet of the 1.5 GeV TPI synchrotron, using the required stored reactive energy, pulse duration, and repetition rate as design constraints. It estimates the number and cost of pulse capacitors, analyzes di…
This paper reports experimental investigations of commutation in two shunt excited DC motors equipped with valve mechanical commutation during speed control by weakening the main pole field. The authors measured interpole supply currents, sparkless zone boundaries, and static commutation stability o…
The paper addresses calculation of commutation armature reaction in direct-current machines whose speed is controlled over a wide range by field weakening, where the commutating reaction magnetomotive force can become a substantial fraction of the main-pole magnetomotive force. It critiques an earli…
This paper examines a combined contactless single-phase synchronous generator intended as a compact high-frequency autonomous power source. It develops a steady-state theoretical model for the machine, treating the effects of the reverse synchronous field and deriving voltage-balance equations with …
This paper formulates an optimization problem for a brushless high-frequency electric-machine amplifier intended as a regulated source for automated systems operating at 100 to 400 Hz. It proposes weight and cost as principal optimality criteria, defines constraints on winding temperature, gain, res…
This paper examines how collector temperature affects the current, voltage characteristics, transition resistance, and voltage drop of sliding brush contacts in commutator electrical machines. Using an equivalent circuit model, the authors analyze experimental data for several brush grades by separa…
A method is presented for calculating the dynamic current-voltage characteristics of sliding brush contacts in commutator electrical machines from parameters obtained through static characteristics on a short-circuited commutator. The approach uses an equivalent circuit including leakage resistance,…
This paper reports experimental tests of a prototype adjustable-frequency electric-machine amplifier with a controlled semiconductor switch at the input, built on the basis of a standard EMA-12A amplifier. The study measures the device’s principal characteristics under active and motor loads, includ…
This article presents an electromechanical adjustable-frequency amplifier that places a controlled semiconductor switch at the input of an asynchronous generator rather than at the output. The proposed arrangement uses semiconductor switching of the excitation winding to create a rotating magnetic f…
The paper analyzes tangential oscillations of carbon brushes in brush commutator assemblies and their influence on commutation, including the phenomenon known as brush whistling. It derives and examines a more detailed equation of brush motion that accounts for friction characteristics, damping, hol…
This paper analyzes design choices for a DC brushless electric machine amplifier formed by two contactless DC machines sharing a magnetic circuit. It derives relationships for distributing electric and magnetic loadings between the two stages, including formulas for output power and gain as function…
This paper describes a portable profilometer designed to study sliding contact mechanics by measuring commutator profiles of electrical machines under static and dynamic conditions, as well as radial and tangential brush vibrations. The instrument uses a shielded double-plate capacitive displacement…
This paper describes an experimental setup for studying sliding brush to commutator contact in collector machines under controlled electrical, mechanical, and thermal conditions. The apparatus uses a variable speed collector, optically synchronized transistor pulse circuitry, adjustable triangular c…
A thermal calculation method is proposed for protected self-ventilated low-power DC machines with armature diameters up to 200 mm and speeds up to 4000 rpm. The method simplifies the armature winding as a uniformly heated body while accounting for different heat-transfer coefficients, insulation and…
This paper describes experimental installations developed for investigating thermophysical parameters relevant to low-power electrical machines, focusing on armature heat-transfer coefficients and the thermal conductivity of winding insulation. It argues that model-based measurements can reduce expe…
This paper examines steady-state heating in enclosed, fan-cooled AO-type asynchronous motors, using extensive copper-constantan thermocouple measurements in the stator winding, rotor, frame, bearing shields, and insulation regions of production and experimental machines. The study describes the resu…
This paper presents a practical thermal calculation method for low-power enclosed asynchronous motors, focused on estimating the mean steady-state temperature rise of the stator winding. The authors reduce a two-loop thermal network to a single-line circuit using experimental observations on heat tr…
The paper addresses the calculation of stator winding overheating as a design constraint in computer-aided optimization of enclosed fan-cooled induction motors. It reformulates the conventional heat-transfer coefficient in terms of external and internal thermal resistances, gives design formulas for…
This paper examines ventilation performance in enclosed asynchronous motors using disk-type fans tested on AO2 series motors and a D-132 motor across varied fan and casing dimensions. It analyzes how air flow rate and ventilation losses depend on relative fan outside and inside diameters, blade widt…
This paper experimentally investigates energy losses in the oscillatory power supply circuit of a betatron using unipolar current pulses, focusing on losses in the electromagnet steel and in an IM-3-100 capacitor bank. Comparing unipolar and sinusoidal operating modes at circuit frequencies around 5…
This paper analyzes commutation in shunt and compound excited DC motors using valve mechanical commutation during armature speed control. It examines how the sparkless operating zone is affected by main pole excitation current, saturation in the interpole flux path, active resistance of commutating …
This paper analyzes how the design parameters of a direct-current machine change when conventional brush commutation is replaced by a valve-mechanical commutation circuit using a doubled commutator and valves in the commutated section. Keeping the main machine ratings and active-part dimensions fixe…
This paper reports an experimental study of a low-power DC machine using a valve-mechanical commutation circuit with diodes connected in the commutated sections during brush short-circuiting. Two otherwise comparable DC machines, one with ordinary commutation and one with the valve-mechanical circui…
This paper analyzes valve-mechanical commutation schemes for direct-current machines, motivated by the limited commutational stability of conventional brush-commutator systems and the practical drawbacks of fully electronic commutation. It classifies proposed circuits into schemes using semiconducto…
This paper examines electromechanical transient processes in asynchronous roller-table motors, emphasizing the effect of steel saturation by leakage fluxes on stator and rotor leakage reactances. The authors formulate the motor equations in a rotating rectangular coordinate system suitable for analo…
This paper examines the asynchronous starting mode of two 7.5 kVA salient-pole synchronous motors with incomplete and complete damper windings. Using exact, approximate, and combined calculation methods, with operational reactances evaluated on a digital computer, it analyzes how rotor asymmetry, st…
This paper analyzes how magnetic rotor asymmetry affects the asynchronous starting characteristics of a synchronous reluctance motor, with special attention to machines without rotor starting windings and to variants with a winding on only one rotor axis. Using Park, Gorev differential equations and…
The article examines methods for calculating the static starting characteristics of salient-pole synchronous machines operating asynchronously, focusing on the dependence of average torque and stator current on slip under steady rotor speed. It classifies available approaches into exact, approximate…
The paper addresses the preliminary design of improved synchronous reluctance motors, focusing on selection of the stator bore diameter and stack length. It proposes a simplified method based on electromagnetic loadings and the standard machine constant formula, deriving expressions that relate calc…
This paper examines how rotor geometry and magnetic circuit saturation affect the power factor and electromagnetic torque of synchronous reluctance motors. Using previously derived magnetic field coefficients, the authors analyze simple and improved rotor designs by relating air gap size, pole overl…
This paper presents a statistical analysis of factory type-test data for three-phase squirrel-cage AO2 series induction motors of frame sizes 1 to 4, manufactured in 1960 to 1968. Treating motor parameters as random variables, the authors test normality using empirical skewness and kurtosis, estimat…
This paper analyzes how manufacturing tolerances affect the performance scatter of explosion-proof induction motors rated 7.5 to 100 kW in the VAO series. Using an analytical tolerance propagation method based on influence coefficients for input dimensions and material characteristics, the authors c…
The paper examines how manufacturing accuracy affects the quality and acceptance testing of low-power asynchronous motors, whose technological parameter scatter may exceed existing standard tolerances. It develops probabilistic tolerance calculations linking deviations in motor output parameters to …
This paper addresses how mechanical and technological scatter in a commutator-brush assembly shortens the commutation period in direct-current machines. It formulates the delay of commutation start and advance of commutation end as random quantities dependent on brush edge geometry, interlamellar sl…
This paper examines the feasibility and energy performance of a single-phase asynchronous impact generator supplying an inductive pulsed load, motivated by the need for economical high-energy pulse sources. Using a mathematical model of the generator transient process, the study evaluates how stator…
This paper develops a mathematical model for transient processes in a single-phase asynchronous impact generator with capacitor excitation, intended for solution on an analog computer. Treating the machine as a special case of a generalized two-phase asynchronous machine, the authors derive differen…
This paper examines the selection of a suitable design for low-frequency unipolar alternating-current generators intended to supply high-current induction stirring systems for molten metals. On the basis of prior technical literature and analogy with direct-current unipolar machines, it argues that …
The paper addresses the calculation of leakage magnetic fields in the end regions of single-layer concentric windings, where three-dimensional geometry and nearby ferromagnetic boundaries make simplified force and inductance estimates unreliable. It formulates the problem in a bounded cylindrical re…
This paper examines electrodynamic forces acting on the end windings of pulse and shock generators during high-current short-circuit conditions, where mechanical loading can be severe and nonuniform. Starting from leakage-field components in cylindrical coordinates, the authors integrate elementary …
This paper examines forced field suppression in impact generators equipped with damper windings, where rapid de-excitation is needed to reduce heating and damage risk after pulsed operation or internal faults. Using an unsaturated machine model with coupled excitation and damper circuits, it derives…
