The design of radiation-hardened circuits the use of special technologies and the use of additional circuit techniques. The efficiency of using these methods to improve the scheme qualitative indicators can be assessed by some evaluation. The paper presents the efficiency evaluation method of special voltage feedbacks application in dynamic loads of the classical differential stages. The stages with dynamic loads are apply, for example, in the schemes of differential and multidifferential operational amplifiers. The purpose of the introduction of these feedbacks is the reducing of the effect of transistors low-signal parameters instability under the influence of destabilizing factors (radiation and temperature). For the organization of feedback circuits in the structure of dynamic loads, additional voltage amplifiers based on transistors are introduced into the circuit. It is shown that this approach can increase the output resistance of the dynamic load and increase the gain coefficient of the differential stage under the influence of ionizing radiation and temperature. The efficiency evaluation method is based on the construction of a mathematical model of the scheme expressed through low-signal differential h-parameters of scheme transistors. Thus, the calculation of the main qualitative indicators of the scheme can be carried out by mathematical modeling. The obtained simulation results confirm the efficiency of the proposed circuit design.
Keywords: efficiency evaluation, circuit design, dynamic load, low-signal parameters, radiation
This article considered individual and unidirectional cooperative mass transfer of two components with a various in the surface-active properties in extraction system carbon tetrachloride - 4% aqueous solution of potassium iodide in the flat interface in the conditions of spontaneous interphase convection. Studied the interaction flow of components in unidirectional cooperative mass transfer on the intensity of mass transfer each other in the conditions of spontaneous interphase convection. Unidirectional cooperative mass transfer acetic acid and iodine increase mass transfer iodine coefficient as compared to its individual mass transfer.
Keywords: spontaneous interfacial convection, Marangoni effect, the cooperative mass transfer, extraction, the mass transfer coefficient, acetic acid, iodine, carbon tetrachloride, the intensity of mass transfer
Purpose: In the first part of the article gives analysis of the impact of various types of the regulators (PI controller, relay and relay operating in sliding mode) on the quality of the transition process in the current loop. It is shown that the best performance in speed and overshoot has a relay regulator operating in sliding mode. In the second part of the article describes a three-loop control system of an electromagnetic bearing gas blower with the capacity of 16 MW The methodology of the work : to calculate the regulator used the method of transfer functions. A switch regulator operating in the sliding mode is used as a current regulator, and to determine the parameters of the speed controller and of the position controller, adjustment onto the modular optimum is performed. The analysis of the transition processes in the three-loop control system is performed in «MatlabSimulink» software. Results: in the result of modelling the electromagnetic bearing control system, transient phenomena by controlling and perturbation actions are obtained. The results are used in the construction of the control system electromagnetic bearing blower pumping unit at the compressor station «Pomarskaya»
Keywords: electromagnetic bearing, three-loop control system, the current loop, relay regulator, modular optimum.
We show that Finland is planning to strengthen the country's role as an international expert in the Arctic, the Arctic is preparing a program of development of transport, energy and environmental technologies. Particular attention is Finland's prospects for economic cooperation in the exploitation of natural resources in the Arctic.
Keywords: Key words: Arctic, international cooperation, natural resources, Finland, economic interests.
The analysis of electromagnetic processes of thyristor controlled voltage regulator consisting of triple-wound transformer with thyristor units is possible only by means of computer modeling. The synthesis of triple-wound transformer by means of block diagram method is concerned here. As a platform for modeling use visual simulation package Simulink. Key assumptions in the development of nonlinear mathematical model of the transformer are generally accepted.
Keywords: three-phase transformer, thyristor voltage regulator, simulation, Simulink
the problems of moisture (cooling) in the mass-transfer apparatus at different parameters of fluid spray and varying the magnitude of the influence of the electric field in the zone of the spray.
Keywords: heat and mass transfer, mist dispersion, electroaerosol, electrostatic dissipation.
The authors examine an alternative method of traction station load balance which needn’t capital investments for technical extension. The authors solve the task of loading partial balancing and suggest exploited transformer construction changing.
Keywords: Balancing transformer, the coefficient reverse sequence, regulation voltage under load.
The article considers the design of modern electrically driven gas-pumping unit (EGPA). The advantages of a smooth adjustment of speed and performance EGPA. Provides an analysis of options for building the power part of the high-voltage frequency converters, used in the composition of the EGPA at compressor stations of main pipelines. Refer to the element base of high-voltage frequency converters. The characteristics of each of variants. The method of work of the frequency converters. Compare the characteristics of frequency converters of various manufacturers. The basic approaches to manufacturing. Defined the most optimal scheme of the power part of frequency converters.
Keywords: frequency converter, topology, design, optimization, structural scheme
Block diagram of the active harmonic filter is considered. State table inverter power switches active harmonic filter is considered. Calculated the capacitance on the DC link active harmonic filters. The calculation takes into account the power converter losses in the active harmonic filter.
Keywords: active harmonic filter, distortion power, energy storage capacitor
The article depicts test results of ballastless track system roadbed stressed state. In-situ tests of roadbed vertical stresses were held considering rolling stock type and speed. Roadbed vertical stress distribution dependence was carried out.
Keywords: Roadbed, ballastless track system, RHEDA 2000, vertical stress damping, stress distribution
Maximum power pointtracking algorithms are widely used in the solar converters in order to obtain maximum power from the solar array. The article provides a brief description of the work of these algorithms, description of the method of testing based on mathematical modeling using Matlab, Simulink and SimScape packages. The results of modeling and comparative analysis of the studied algorithms, its strengths and weaknesses revealed.
Keywords: maximum power point, maximum power point tracker, photovoltaic, buck converter, comparative study of algorithms, perturb and observe method, constant voltage method, constant current method, icremental conductance method
Information about authors of issue (№1 2014)
Keywords: authors
A long term study of compensation converters allowed to solve the task of designing the structure, the calculation of its elements, the determination of static characteristics and energy performance. Thus remain undeveloped algorithms of their work to ensure a successful use of compensatory converters and independent control of active and reactive power consumption. An algorithm of their work to ensure the optimal use of compensatory converters. This article contains material from GC № 16.526.12.6016 11.10.2011.
Keywords: Site load electric network compensation converters; management algorithms ; controlled electric drive with compensation rectifier in section of the direct current of the converter of the frequency
An optimal control algorithm for compensating converters. This algorithm provides control of active and reactive components of power consumption. The algorithm allows to reach a balance between the values of the angles controls αi and αe . In the algorithm used is a method for solving equations by iteration. In article materials of the state contract № 16.526.12.6016 on 11.10.2011.
Keywords: compensation converter, frequency converter, control algorithm, objective function, iterative method
Discusses the features of mates renewable эергии (RES), and also technological platforms, as well as measures to support industry. Shows the results of modeling of wind power systems and the conclusions about the dependence of the output parameters of stochastically varying input parameters
Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production