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In this paper, the dispersion characteristics of slow-wave structures suitable for use in devices in the terahertz range are calculated. Slow-wave structures of “winding waveguide” and “counter pins” types can be considered as suitable systems. Analysis of dispersion characteristics of slow-wave structure was carried out by a waveguide-resonator model, which is built for the slow-wave structure of...
For analysis of power consumption of resistance spot welding systems field-circuit modelling is required. It includes both 2D eddy-current FEA analysis for estimation of the leakage impedance of transformer and P-Spice program for the circuit simulation. It is shown that the design of the transformer influences on the output current and power consumption. We used the equivalent circuit of three-winding...
The paper proposes an original equivalent circuit of the multiwinding transformer based on the classical theory of transformers and the introduction of a new parameter — the mutual inductance on leakage fluxes. The results of the calculation of currents and losses in the windings of a powerful toroidal transformer on the base of the original equivalent circuit of the multiwinding transformer are confirmed...
The article reviews the physical basis of the theory of electric drive with the field regulated reluctance machine (FRRM). The requirements as part of a systematic approach to the development of the valve electric drive to a modern regulated electric drive, leading to the improvement of the processing technique. Considered distinctive features, operating principle, high specific indicators, the analysis...
According to service rules the number of coil's windings of power transformer is adjusted to obtain the normal voltage value on consumer side. Usually it is required in winter time, when load power is growing. The turns ratio declining leads to the rise of the voltages on the transformer second winding and on the consumer's distribution bus. The paper main goal is to show that sometimes it is desirable...
The article reviews with electrical machines in modern regulated electric drives. The advantages of the complex “controlled converter — motor” for example, variable frequency synchronous drive. Specified effects on more efficient use of the active materials in the electrical machine and reduce electrical losses by varying the air gap between the rotor and the stator and rotor grooving. Two variants...
The article discussed the features of the calculation of the electromagnetic torque of the field regulated reluctance machine. It shows a clear interpretation of the mechanism of formation of the electromagnetic torque in a multiphase salient pole of the field regulated reluctance machine (FRRM). We compared the calculated (by analogy with DC motors) and experienced engine data FRRM, drawn conclusions...
The paper considers main hardware designed for improvement of electromagnetic compatibility arc furnaces. The furnace power mode is proven to be of a dramatically variable and non-stable nature affecting economic performance of the furnace adversely. The authors provide a detailed description of the method stabilizing power parameters of the arc furnace due to a contactless and high-speed control...
The paper describes the process of creating of BLDC's digital control system. The BLDC has no speed sensor, so back-EMF method is used for commutation control. Authors show how to model the control system in MatLab/Simulink and to test it onboard STM32F4 microcontroller.
At present current-limiting reactors are widely used in order to limit levels of fault currents in electrical networks. Reactor being an element of power system must be able to operate reliably under nominal and fault conditions. Main attention in the paper is focused on calculation method of reactor, operating under nominal condition. A comprehensive approach to calculation of a design of dry type...
In high-voltage electric power systems current-limiting devices are applied to limit a fault current levels, among those current-limiting reactors are extensively applied. In the comprehensive design a particular attention is paid to winding design. Generally, winding is performed using a few parallel wires (branches). The transition between horizontal rows is based on a specific algorithm referred...
It is shown that an important factor specifying the transient process of the synchronous machine during disturbances is the account of mutual induction in the leakage flow path between the field winding and the equivalent damping circuits of the generator. Justified a refined equivalent circuit, includes explicitly the specified mutual induction of rotor circuits. The calculation result compared with...
This paper presents the efficiency of the phase-shifting transformer (PST) installation in the power supply system of Saint-Petersburg and the Leningrad region which allows to maintain power flows within the defined range and to limit short-circuit currents to the values which do not exceed the breaking capacity of switching devices. After the analysis of various PST operation conditions, its optimum...
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