3D Modeling of Electromagnets Fed by Alternating Voltage Source

2005 ◽  
Author(s):  
T. Drehier ◽  
G. Meunier
1993 ◽  
Vol 29 (2) ◽  
pp. 1341-1344 ◽  
Author(s):  
T. Dreher ◽  
G. Meunier

Author(s):  
V. F. Bolyukh ◽  
I. S. Schukin ◽  
J. Lasocki

Purpose. The purpose of the article is to determine the influence of the initial displacement of the windings on the indicators of an electromechanical induction accelerator of a cylindrical configuration with pulsed excitation from a capacitive energy storage and with short-term excitation from an alternating voltage source. Methodology. To take into account the interrelated electrical, magnetic, mechanical and thermal processes, as well as a number of nonlinear dependencies, we use the lumped parameters of the windings, and the solutions of the equations describing these processes are presented in a recurrent form. The mathematical model of the accelerator takes into account the variable magnetic coupling between the windings during the excitation of the inductor winding. When calculating the parameters and characteristics of the accelerator, a cyclic algorithm is used. Results. At a frequency of an alternating voltage source of 50 Hz, the current amplitude in the armature winding is less than in the inductor winding. With an increase in the source frequency to 250 Hz, the phase shift between the winding currents decreases. The current in the inductor winding decreases, and in the armature winding it increases. The accelerating components of the force increase, and the braking ones decrease. With an increase in the source frequency to 500 Hz, the current density in the armature winding exceeds that in the inductor winding. In this case, the phase shift between the windings is further reduced. Originality. When a cylindrical accelerator is excited, the largest amplitude of the current density in the inductor winding occurs at the maximum initial displacement of the windings, but the amplitude of the current density in the armature winding is the smallest. The largest value of the current density in the armature winding occurs in the absence of an initial displacement. When excited from a capacitive energy storage, the electrodynamic force between the windings has an initial accelerating and subsequent braking components. As a result, the speed of the armature initially increases to a maximum value, but decreases towards the end of the electromagnetic process. When a cylindrical accelerator is excited from an alternating voltage source, a phase shift occurs between the currents in the windings, which leads to the appearance of alternating accelerating and decelerating components of electrodynamic forces. The accelerating components of the force prevail over the braking components, which ensures the movement of the armature. Practical value. At a frequency of an alternating voltage source of 50 Hz, the highest speed at the output of the accelerator vzf=0.5 m/s is realized at an initial displacement of the windings z0=6.2 mm, at a frequency of 250 Hz, the highest speed vzf=2.4 m/s is realized at z0=3.1 mm, and at a frequency of 500 Hz the highest speed vzf=2.29 m/s is realized at z0=2.3 mm.


2021 ◽  
Vol 1 (42) ◽  
pp. 39-43
Author(s):  
Leonid Yuferev ◽  

At the heart of a micro-grid that includes several sources of electrical energy, including renewable energy, there must be a base (reference) source that sets the voltage and frequency in the network. (Research purpose) The research purpose is in developing a basic voltage source of a micro-grid, which includes renewable energy sources. (Materials and methods) The article shows that the sources of electrical energy are different, but the main requirement for them is to be able to supply voltage to the electrical network at any time, there is a standard voltage scale in the network. For a micro-grid, which will include various sources of electrical energy with a total power of up to 25 kW, you can limit yourself to a voltage of 220 V and a single-phase electrical network. (Results and discussion) The article presents a block diagram; technical characteristics and electrical diagram of the inverter of a single-phase basic voltage source; a method for calculating the output filter of the inverter based on pulse-width modulation technology. (Conclusions) When using renewable energy sources in the micro-grid, it is necessary to take into account that there are periods of time in which they do not generate electrical energy and choose as the base one that will not have such moments, or you need to use a temporary electricity storage device. It is possible to use a chemical source or a battery of accumulators as a base source. When creating a micro-grid of alternating voltage, an inverter is added to these sources from constant voltage to alternating voltage. The article presents a block diagram of a base voltage source with an AC output reference voltage to create a micro grid with a power of up to 25 kW.


2021 ◽  
Vol 9 (04) ◽  
pp. 34-43
Author(s):  
K. Fernand Koffi ◽  
◽  
Agoua Raoule ◽  
Diety Landry ◽  
Georges Loum ◽  
...  

The need to use SPWM controlled voltage inverters in MV, led us to examine how to filter alternative signals with filters (L-C) and (RL-C). This allowed us to decide on the use of certain formulas for calculating the elements of these filters. Likewise, we have proposed a method of calculating the resistance R by mathematical iterations without using the quality factor Q, in order to obtain a low error rate between the RMS values and the fundamental effective values and THDs respecting the standard 519 IEEE - 2014. The results of these studies obtained using the MATLAB-SIMULINK software are presented in the penultimate session of this article. Nomenclature SPWM Sinusoidal Pulse-Width-Modulation THD Total Harmonic distortion SN Apparent power of the alternating load MV Medium voltage alternating voltage (1 kV --- 50 kV) Uph phase-to-phase voltage at the ac load RMS Root Mean Squared R L C Resistance Inductance Capacitor MVDC Medium voltage direct current VSI Voltage Source Inverter


2013 ◽  
Vol 27 (11) ◽  
pp. 1330007 ◽  
Author(s):  
FEIFEI LI

This paper reviews the method of bosonization for one-dimensional interacting fermions. Example of its application to mesoscopic systems is presented with an explicit calculation of the spin and charge currents in an interacting quantum wire subject to a uniform magnetic field and alternating voltage source. Special emphasis is given to the details of the calculation using bosonization and Keldysh techniques.


2021 ◽  
Vol 2021 (3) ◽  
pp. 28-36
Author(s):  
V.F. Bolyukh ◽  
◽  
I.S. Shchukin ◽  
◽  
◽  
...  

The purpose of the article is to evaluate the efficiency of an induction-type linear pulse electromechanical converter (LPEC) when operating in shock-power mode and excitation from an alternating voltage source (AVS) in comparison with excitation from a capacitive energy storage (CES). A mathematical model of an induction-type LPEC has been developed both when excited by a unipolar pulse from a CES and from an AVS using lumped parameters of the windings, which takes into account the interrelated electromagnetic, mechanical and thermal processes. It has been found that when the LPEC is excited from the AVS with a voltage frequency of 50 Hz, the electrodynamic force takes on a periodic decaying character with a significant prevalence of positive components of forces over negative ones. The maximum value of the force is much less, and the value of its impulse is much greater than in the LPEC, excited from the CES. With an increase in the frequency of the AVS voltage from 50 to 150 Hz, the highest value of the current density of the inductor winding decreases, and in the armature winding it increases. The greatest values of force and impulse of force are realized at a voltage frequency of 150 Hz. With an increase in the AVS frequency, the relative indicator of the efficiency of the LPEC increases. References 15, figures 4.


2012 ◽  
Vol 516-517 ◽  
pp. 1508-1511
Author(s):  
Xian Feng Zheng ◽  
Yun Hua Dong ◽  
Jing Zhang

Causes of induced electromotive force (emf) in other circuit are analyzed when a single loop in control cable is connected to an alternating voltage source in this paper. The size of induced emf and its influence factors are discussed. Based on theoretical analysis and test, the control measures of induced emf in control cable are put forward.


2020 ◽  
Author(s):  
Christopher S. Graffeo ◽  
Avital Perry ◽  
Lucas P. Carlstrom ◽  
Michael J. Link ◽  
Jonathan Morris

2018 ◽  
Vol 1 (1) ◽  
pp. 54-66
Author(s):  
Rakan Khalil Antar ◽  
Basil Mohammed Saied ◽  
Rafid Ahmed Khalil

A new control strategy for active power filters is proposed, modeled and implemented in order to improve the power quality of a line commutated converter High voltage DC link. The ability of reactive power and harmonics reductions are generally met by using passive and active power filters. In this paper, modified active power filter with a modified harmonics pulse width modulation algorithm is used to minimize the source harmonics and force the AC supply current to be in the same phase with AC voltage source at both sending and receiving sides of a line commutated converter high voltage DC link. Therefore, it is considered as power factor corrector and harmonics eliminator with random variations in the load current. The modified harmonics pulse width modulation algorithm is applicable for active power filter based on a three-phase five-level and seven-level cascaded H-bridge voltage source inverter. Simulation results show that the suggested modified multilevel active power filters improve total harmonics distortion of both voltage and current with almost unity effective power factor at both AC sides of high voltage DC link. Therefore, modified active power filter is an effective tool for power quality improvement and preferable for line commutated converter high voltage DC link at different load conditions.


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