CC BY
4
UDC 621.313: 621.92: 537.8
https://doi.Org/10.20998/2074-272X.2021.4.02
V.I. Milykh, M.G. Tymin
A COMPARATIVE ANALYSIS OF THE PARAMETERS OF A ROTATING MAGNETIC FIELD INDUCTOR WHEN USING CONCENTRIC AND LOOP WINDINGS
Introduction. Three-phase inductors of a rotating magnetic field are used in grinders, separators and stirrers for the technological processing of bulk and liquid substances. This occurs in a cylindrical working chamber under the influence of ferromagnetic elements in the form of pieces of iron wire, which move together with the field. Problem. By analogy with three-phase induction motors, for the stator of inductors a concentric winding is adopted, which is a diametric single-layer winding. When moving from such motors to an inductor, its operating conditions have changed due to the significantly increased non-magnetic space inside the inductor compared to the motor clearances. The difference in the frontal parts of the phase windings has become essential for the electromagnetic parameters and the structure of the magnetic field in the inductor working chamber. Therefore, a loop shortened stator winding, which is symmetrical, can be considered as an alternative to a concentric diametric winding. Goal. The aim of the work is to compare the dimensional and electromagnetic parameters of a rotating magnetic field inductor in two versions of its three-phase winding: concentric single-layer diametrical and loop shortened two-layer. Methodology. Comparison of the windings is carried out through a detailed analysis of the geometrical parameters of their frontal parts, as well as through numerical-field calculations of the electromagnetic parameters of the inductor as a whole and the distribution of the magnetic field in its working chamber. Results. A significant difference in the geometrical parameters of the frontal parts of the two windings under inductor conditions was revealed. The loop version of the winding makes it possible to reduce the length of the winding conductor, its active resistance, as well as the reactance of its frontal dissipation. At the same time the asymmetry of the phase windings is excluded and an increase in the homogeneity of the magnetic field in the inductor working chamber is provided. Originality. The scientific novelty of the work lies in the development of a method of comparative analysis of the windings under the conditions of the rotating magnetic field inductor and in revealing the advantages of a loop shortened winding compared to the used concentric diametric winding. Practical value. The loop shortened stator winding recommended for the inductor will eliminate the asymmetry of its electromagnetic system. Thereby, the quality of its work in the technological processing of different substances is significantly increased due to ensuring the homogeneity of the magnetic field in the working chamber. At the same time, the copper conductor of the winding is still saved, and the efficiency of the inductor is also increased by reducing the power of electrical losses. References 12, tables 5, figures 12.
Key words: rotating magnetic field inductor, stator winding versions, geometrical and electromagnetic parameters.
Розглянутий трифазний тдуктор обертового магттного поля для теxнологiчноi обробки pi3Hux речовин. Виконаний aH^i3 переваг i недолжв петльовоi укороченоi обмотки його статора, яка пропонуеться як альтернатива використовуваноi концентричноi дiаметральноi обмотки. Порiвняння обмоток проводиться за допомогою детального аналiзу геометричних параметром ix лобових частин, а також електромагнтних параметрiв тдуктора в цыому за допомогою чисельно-польовихрозрахунюв. Виявлено, що петльовий варiант дозволяе зменшити активний i реактивний опори лобового розЫяння обмотки i, що найсуттевiше, виключити несиметрж фазних обмоток, забезпечуючи тдвищення однорiдностi магттного поля вробочш камерi тдуктора. Бiбл. 12, табл. 5, рис. 12.
Ключовi слова: шдуктор обертового магштного поля, BapiaHra обмотки статора, геометричш i електромагштш параметри.
Рассмотрен трехфазный индуктор вращающегося магнитного поля для технологической обработки разных веществ. Выполнен анализ преимуществ и недостатков петлевой укороченной обмотки его статора, которая предлагается как альтернатива используемой концентрической диаметральной обмотки. Сравнение обмоток проводится посредством детального анализа геометрических параметром их лобовых частей, а также электромагнитных параметров индуктора в целом посредством численно-полевых расчетов. Выявлено, что петлевой вариант позволяет уменьшить активное и реактивное сопротивления лобового рассеяния обмотки и, что наиболее существенно, исключить несимметрию фазных обмоток, обеспечивая повышение однородности магнитного поля в рабочей камере индуктора. Библ. 12, табл. 5, рис. 12. Ключевые слова: индуктор вращающегося магнитного поля, варианты обмотки статора, геометрические и электромагнитные параметры.
Introduction. Technological processing of various materials in grinders, separators and mixers is carried out using a magnetic field [1-8]. Including bulk and liquid substances are processed in inductors of a rotating magnetic field (IRMF) - electromagnetic mills [3, 4, 6-8]. This occurs under the influence of ferromagnetic elements (FEs) in the form of pieces of iron wire in a cylindrical working chamber, through which in the axial direction the processed substance is passed. Such elements move with a magnetic field, creating a so-called «vortex layer» in the chamber.
Initially, the inductors had a ferromagnetic core with three explicit poles, which housed the coils of a three-
phase AC system [1]. This inductor design was replaced by an implicit-pole electromagnetic system similar to the stator of three-phase induction motors (TIM).
The energy level and dimensions of the inductors which are developed and operated correspond to the TIM with power of the order of units and tens of kilowatts. Therefore, taking into account the experience of their creation and operation [9], for inductors a fairly simple three-phase concentric diametric single-layer winding is adopted.
However, during the transition from TIM to the inductor, the conditions of its operation have changed
© V.I. Milykh, M.G. Tymin
significantly due to the fact that the non-magnetic space inside the inductor has increased by two orders of magnitude compared to the gaps of the motor. If earlier the voltage drop across the active resistance and reactive resistance of the frontal scattering of the phase windings were units of percent of the electromotive force (EMF) on the active length of the machine, then in the inductor they are already commensurate. Under such conditions, the asymmetry of the frontal parts of the phase windings, which is inherent in the specified concentric winding, becomes significant. Also unfavorable is the pronounced «stepwise» distribution of the magnetomotive force (MMF) of the three-phase diametrical winding along the line of the boring circle of the stator core.
The theory of electric machines shows that a three-phase loop shortened winding, which is two-layer is deprived of these shortcomings [9]. However, for technological reasons, such a winding is considered acceptable in TIMs only as their power and dimensions increase.
The feasibility of using a loop winding in the IRMF instead of concentric one can be identified by comparing them in its conditions. The adequacy of this comparison has recently increased due to the development of methods for calculating electromagnetic parameters and characteristics of the inductor based on numerical calculations of magnetic fields [10, 11].
The goal of this work is to compare the dimensional and electromagnetic parameters of the inductor of a rotating magnetic field with two variants of its three-phase winding: concentric single-layer diametrical and loop shortened two-layer.
Object of study. The three-phase inductor is bipolar. Its electromagnetic system is given by its cross section in Fig. 1. The geometric parameters of the inductor are due to given for technological reasons the active length la = 250 mm and the radius of the inner surface r^ = 47 mm of the working chamber at the average value of the magnetic flux density in it Bav = 0.12 T. This is due to the axial length of the stator core ls, which is equal to la, the radii of its boring rsi = 0.06 m and the outer surface r„ = 0.109 m.
a = MZ
The core is made of electrical steel grade 2212 with thickness of 0.5 mm and has filling factor KFe = 0.95. The connection scheme of the winding is «star», and its phase has Ns = 72 turns. The shell of the chamber is 5e = 5 mm thick and is made of non-magnetic stainless steel.
The inductor with the listed parameters was investigated in [11], where the calculation revealed the rated phase voltage of the stator winding UsN = 100 V at frequency f = 50 Hz, but there another problem has been considered.
The structures of the compared variants of the winding - concentric diametric and loop shortened are given in Fig. 2, 3, where Tp is the pole step. And for the second of them the coefficient of relative shortening ps = 10/12 is chosen.
Fig. 2. Three-phase two-pole concentric single-layer stator winding
Fig. 1. Cross section of the IRMF electromagnetic system: 1 - laminated ferromagnetic core; 2 - slots with winding; 3 - ventilation ducts; 4 - shell of the working chamber
i "2 m
Fig. 3. Three-phase two-pole loop two-layer with shortened step stator winding
The distribution of phase windings in the slots of the stator is shown in Fig. 4, 5 in cross section of the electromagnetic system of the inductor.
In the example in Fig. 4 in the working chamber there are no FEs, and this corresponds to the ideal idle (II). In Fig. 5 the chamber is filled with FEs, which are oriented along the >"-axis, and the magnetic field is rotated by the angle &, which is, as considered in [10], the load angle in the corresponding mode of operation of the inductor.
T
T
Fig. 4. Structure of the single-layer diametric winding and the magnetic field in the ideal idle mode
Fig. 5. Structure of the two-layer shortened winding and the magnetic field in rated load mode
The structure shown with a uniform distribution of FEs in the working chamber is idealized, as in [1, 10, 11], and it is required for an accessible organization of calculations. The real structure of the elements is usually less ordered.
FEs are made of steel St3. Their sizes and intervals between them are taken as in [11], which can be understood in Fig. 5, where everything is depicted on a single scale. An important parameter is the fill factor of the chamber with them in the xy-plane KFes, which is 0.32. The same coefficient is taken in the yz-plane: then the volume fill factor KFev has a value of 0.1.
For the winding options considered in Fig. 4, 5, the operating modes can be changed, but in general the pictures of the magnetic field are almost preserved.
In the cross section of the IRMF (see Fig. 1), the magnetic field is considered plane-parallel [10]. Therefore round sections of FEs are replaced by square ones with the corresponding recalculations of the sizes.
Fundamentals of numerical field calculations. The source of the rotating magnetic field in the inductor is a three-phase system of currents of the phase windings:
iA = /mcos(oV + P);
iB = Imcos(cost - 2%/3 + p); (1)
ic = Imcos(rnst + 2% / 3 + P), where t is the time; Im is the current amplitude; as is the
angular frequency; ¡3 is the initial phase of the currents, which sets the required for a particular mode of calculation angular displacement of the direction of the MMF of the stator winding Fs directed by the y-axis.
An example of this is shown in Fig. 5, where 3=26.7°. Figure 4 shows the directions of currents in the phase windings in the II mode, in which ¡3=0, and therefore the vector of the MMF Fs is directed along the y-axis.
The magnetic field of the inductor in its central cross section is described by the well-known 2D differential equation [10, 12]:
ro%-1rot(£Az)] = kJz , (2)
where fia is the absolute magnetic permeability; k is the unit vector along the axial z-axis; Az, Jz are the components of the magnetic vector potential and current density.
The propagation of the magnetic field is limited by the Dirichlet boundary condition Az = 0 on the outer surface of the core. The effect of the camera shell on the magnetic field is considered insignificant.
The provided research tools are numerical calculations of the magnetic field by the Finite Element Method according to the FEMM computer code [12] with control by the created Lua script. In general, the method of calculating the magnetic fields of the inductor and its electromagnetic parameters, as well as the rationale for the accepted assumptions are described in detail in [10, 11], so in this work this is not repeated.
The voltage equilibrium in the phase winding of the stator corresponds to the complex equation [10]:
Us =-Ea + jXvI_s + (Rs + Rmag )Ls , (3)
where the complexes of its current and EMF En, which is created on the active length of the winding, are presented.
Formula (3) also includes the active resistance Rs and the reactive resistance of the frontal scattering Xv of the phase winding, as well as the active resistance Rmag, which reflects the power of the magnetic losses and is determined during the iterative calculation of the magnetic field [10].
Comparative calculations of geometric parameters of winding variants in the inductor.
Figures 4, 5 already show the accepted shape of the semi-closed slot of the inductor, which is trapezoidal with rounding, which is characteristic of induction motors of the same size.
Figure 6 shows the structure of the insulation of the slot, which for the two-layer winding is supplemented by a jumper. Detailed calculations show that in the case of a single-layer winding, the useful cross-sectional area of the slot remaining for the conductors, Ssn=274 mm2, and in the case of a two-layer winding, it decreased by 4 mm2 or 1.5 %.
For clarity of further illustrations for the winding, the adopted diameter of the uninsulated effective conductor dsc = 3 mm, and of the insulated one is dscis = 3.46 mm, and in the slot their number is zQs = 18. For technological reasons, the effective conductor can be divided into elementary conductors of smaller diameter.
Fig. 6. Estimated model of the slot with insulation (bcis - insulation thickness): a - with a single-layer winding, b - with a two-layer winding (dimensions in mm)
The main difference between the given variants of a winding consists in their frontal parts, and here the careful calculation analysis is applied.
The design of the frontal parts of the single-layer concentric winding is shown in Fig. 7 - in the longitudinal section of the inductor, as well as in Fig. 8 as a view of the ends of these parts.
Fig. 7. Frontal part of the concentric winding in the meridian section: 1, 2, 3 - phase windings; 4 - surface of the core; 5 - slot with the winding rod; 6 - axial ventilation channel
Fig. 8. Frontal part of the concentric winding (end view): 1, 2, 3 - phase windings; 4 - slot with the winding rod;
5 - core boring surface
The whole structure depends on the size of the «harness» of the conductors, which is formed in a rectangular section, and Fig. 7 shows its dimensions hf and bf (in mm) together with the surface insulation. The figure is shown in proportion, and all dimensions are marked on it without providing a number of values just to reveal the degree of detail of the calculations.
The design of the frontal parts of the two-layer loop winding is given in Fig. 9, where two sections are left from a flat scan (see Fig. 3), as well as a view in longitudinal section of the inductor (right). Here, one harness contains half the number zqs, i.e. 9 conductors, and its dimensions hf and bf together with the insulation were 11 mm. In Fig. 9, as in Fig. 7 the proportions of the sizes are saved, but all set of their designations is shown for display of a measure of detailing of calculations.
Fig. 9. Calculation model of the frontal part of the loop two-layer winding with indication of the size of its elements
The frontal parts of the windings are sparse, gaps are provided between them. This is necessary in conditions of high current density in the winding and a complicated cooling and ventilation system in the inductor compared to induction motors. Facilitation of cooling and ventilation is achieved by the introduction of axial ventilation ducts in the stator core, which is not practiced in induction motors of appropriate dimensions. However, the study of this issue is beyond the scope of this article and will be considered separately.
On the basis of calculation models of frontal parts of windings, detailed calculations of their sizes are carried out that allows to carry out their comparative analysis. First of all, Table 1 shows the basic geometrical parameters of two variants of the inductor winding (hereinafter 1sl - single-layer concentric diametrical; 2sl - two-layer shortened loop).
Table 1
Lengths of the elements of single- and double-layer windings
Version hfs lfs lfhav lWav lcsav
mm mm mm mm m
1sl 70 103 460 1420 102
2sl 58 145 379 1259 91
The dimensions indicated in Table 1: hfs - the farthest deviation of the winding from the boring core; f - the outreach of the frontal part of the winding; l^ and lWav - the length of the wire of the frontal part and the coil of the average coil; lcsav - the length of the wire of the average phase winding.
The average length of the coil is the sum of the lengths of the rectilinear slot ls and the curved frontal parts lfhaw of the winding:
lWav = 2(ls + lfhav)- (4)
The total length of the conductors of the phase winding
lcs = lWav Ns. (5)
According to the indicators hfs and j (Fig. 7, 9), which affect the dimensions of the inductor, the windings have both advantages and disadvantages, but in terms of the volume h^xlj the double-layer winding loses by 17 %, although in the total volume of the inductor it will have a much smaller share. But the gain in diameter through h^ has priority over the loss in axial length through js.
The structure of the sections of the loop winding (see Fig. 3) is always symmetrical. The concentric winding has six different variants of the coils (Fig. 2), and their asymmetry (see Fig. 7) occurs due to different lengths of the wire of the frontal parts lfavh. But for comparison in Table 1 the lengths l^av and lWav of the average coil are taken. As a result, the loop winding has the advantage of a shorter wire length lcs of the phase winding by 12 %. In addition to saving copper, this helps to reduce the active and reactive resistance of this winding.
However, the disadvantages of the concentric winding are manifested not only in this, but also in the asymmetry of the phase windings as a whole due to the difference of their individual coils, which is explained in Table 2. Here the calculated dimensions of the elements of this winding are indicated: ljhawk, lWavk - the average lengths of the frontal parts and individual coils; lWavf, lcf -the average lengths of turns and all wire of phase windings, and the made designations of versions of coils correspond to Fig. 7: 1, 2, 3 - the number of phase winding; a, b, c, d - the version of its coil.
Table 2
Lengths of the elements of the concentric winding
Version 1a 1b 2c 2d 3c 3d
Ifhawb mm 324 402 429 635 382 589
Iwavk, mm 1149 1305 1357 1770 1264 1677
lWavf, m 1227 1564 1471
If m 88 113 106
Manifestation of asymmetry is the difference of the largest and smallest sizes: l-hawk by 96 %, lWavk by 54 %, lWavf and lcf by 28 %, and the reason for this is the frontal parts of the phase windings.
For low and medium power machines for practical calculations empirical formulas that take into account the main features of the design forms of the coils are used [9]. For the coil of the bulk concentric winding of the stator, the following winding lengths are obtained: lcs = 80.3 m; lwav = 1115 mm; j = 307 mm; j = 75.2 mm. It is seen that the classical technique, in comparison with the developed method, gives significantly underestimated parameters of the windings lcs and lWav - by 21 %; j - by 33 %; j - by 27 %. That is, the classical approximate technique does not take into account the features of the stator winding of this inductor.
For a two-layer loop shortened winding the classical technique according to the corresponding formulas gives lengths: j = 302 mm, j = 97.5 mm, lWav = 1104 mm, lcs = 79.5 m, which differs from the developed refined method by 20.3 %, 32.8 %, 12.6 % and 12.3 %, respectively.
Stator phase winding resistances. The calculated geometric parameters of the windings allow to determine their active resistances and reactive resistances of the
frontal scattering included in (3). Reactive scattering resistances on the active length of the winding are automatically taken into account in the EMF Ea, which is determined by calculating the magnetic field at this length.
Active electrical resistance of the phase winding, reduced to the accepted operating temperature Tw = 115 °C:
, , pCu Tb cs krkTCu-"-, (6)
Rs — kv kj
Ss
where Scs is the cross section of the effective conductor, m2; pTb = 1.75 10-8 Q-m is the resistivity of copper winding at base temperature Tb = 20 °C; kTbCu = 1+aT-(TM,-Tb) is the temperature coefficient of resistance (kTbCu=1,38); aT = 0.004 °C-1 is the specific temperature coefficient of resistance of copper; kr is the coefficient of increase of resistance due to current displacement (following [9], kr = 1).
Inductive resistance of the frontal scattering of the phase winding of the stator is determined by the classical method [9], which is common to given types of winding:
Xv —1,58
fsh N2 X
a fh
p qs 108
(7)
where the scattering conductivity factor of the frontal parts of the stator winding
X
sfh
- 0,34^iljh -0,64ps Tp); (8)
where qs is the number of slots per pole and phase.
Comparison of resistances (p.u.) of single-layer (1sl) and double-layer (2sl) windings are given in Table 3. The advantage of the second of them in terms of resistance is obvious: active resistance is 11 % lower, reactive resistance of frontal scattering is lower by 18 %. When calculating for a concentric winding, its parameters are taken as average, accordingly, the parameters in Table 3 are averaged.
Table 3
Electrical parameters of windings
Version Xs fh Is Ea Uv Ur
Q p.u. Q A V V V
1sl 0,349 1,847 0,473 59,9 69,4 28,3 21,6
2sl 0,310 1,516 0,378 66,5 72,0 25,1 21,4
The conditional active resistance Rmag included in (3) depends on the load level of the inductor and is in the range 0.01-0.014 Q.
Analysis of the electromagnetic parameters of the inductor in the ideal idle mode. The initial calculations of the electromagnetic parameters of the inductor are performed in the II mode, the essence of which is the absence of ferromagnetic elements in the working chamber. It is for this mode that the required value of the magnetic flux density Bav in this chamber is set, and it is the most intense in terms of the stator winding current that given in [11].
At rated voltage UsN, the effective values of current Is, EMF Ea and voltage drops Uv = X,JS and UR = (Rs+Rmag)Is have the values shown in Table 3. There is a significant effect on the equilibrium of voltages of their drops, which leave for the main EMF about 70 % of
the input voltage, while, for example, in induction motors it reaches more than 95 %.
Electrical and energy parameters of the inductor for the two versions of the winding in the II mode are given in Table 4, where Pels, Pmags - the power of electric and magnetic losses; Jsc - the current density in the conductor; As - the linear current load on the core boring.
Table 4
Comparison of electrical and energy inductor parameters when using different windings
Version Pels P ± mags Bav Jsc As
W W T A/mm2 A/cm
1sl 3760 43 0,117 8,48 687
2sl 4100 41 0,125 9,40 761
Graphs of distribution of the module of the magnetic flux density B in the core of the inductor are given in Fig. 10, 11. They correspond to the II for a symmetric current system with the values in Table 3 (for a concentric winding it is conditional with averaging of phase windings).
Fig. 10. Distribution of the magnetic flux density along the pole arc (left - on the average radius along the height of the tooth, right - on the surface of the working chamber)
0,02
5T ,2s/
Is/"
40 30 20 10 0 10 20 30 40
The reactive resistance of the slot part of the winding Xa = EJIS is introduced, which was 1.159 Q and essentially takes into account the mutual inductive resistances of all phases, because the phase EMF Ea was determined by the magnetic field of the entire three-phase winding.
The difference in the parameters of the three windings arose due to the different lengths of their frontal parts, given in Table. 5. Therefore, there are active Rs and reactive Xv resistance, which are shown in the same table.
Table 5
Comparison of inductor phase parameters for concentric winding
Phase winding lfh Xv Rs Zs Is
mm Q Q Q A
1 363 0,473 0,275 1,529 65,30
2 532 0,573 0,403 1,776 56,16
3 486 0,508 0,368 1,708 58,55
av 460 0,473 0,349 1,671 59,85
To eliminate the «skew» of the phase voltages, the concentric winding is fed by a «star» circuit with a neutral wire N (Fig. 2). Then the separate impedance for each phase
2s =
JcR
s + Rmag
)2 + (Xa + Xv )2
(9)
Fig. 11. Distribution of the magnetic flux density along the horizontal central axis within the working chamber
The graphs show that from the point of view of uniformity of distribution of the magnetic flux density the loop shortened winding has an advantage, besides it gives slightly more value of the magnetic flux density in the working chamber. And the nonuniform distribution in both cases is caused by the discrete structure of the stator winding.
If we consider the individual phase windings, then in its loop version, symmetry is its essence. Consequently, in the case of a concentric winding, due to differences in the parameters of the phase windings (see Table 2), there is a significant asymmetry of the phase currents and other electrical quantities. And this leads to known problems, the basis of the analysis of which is the following approximate method.
and the phase current Is = Us/Zs are calculated.
The obtained asymmetric current system is given in Table 5. In addition to the parameters of the numbered phase windings 1, 2, 3, it also presents the parameters of the averaged winding av.
The obtained effective values of phase currents are substituted in (1), and a number of calculations of the magnetic field when changing fi from 0 to 180° with a step of 2° is carried out, which provided a simulation of the rotation of the magnetic field.
At each calculation point, the values of the magnetic flux density were determined at fixed points of the working chamber: 1 - in the center; 2, 3 - in the upper and right boundary points.
The results of calculations for the asymmetric concentric winding are given in Fig. 12 compared to similar graphs for a symmetrical loop winding. The graphs show the advantage of a loop winding, which provides almost stable magnetic flux density. With a concentric winding, there are significant pulsations of the magnetic flux density, because the asymmetric current system gives an elliptical magnetic field.
Fig. 12. Changes in the magnetic flux density at fixed points of the working chamber during the rotation of the magnetic field: 1 - in the center; 2, 3 - on the surface at the top and right
Conclusions.
1. The developed technique allows on the basis of a single approach to calculate the geometric parameters of the frontal parts of concentric and loop windings taking into account their detailed structure and size of all components, which gives much more accurate results compared to classical methods of designing electric machines.
2. In the conditions of the inductor of a magnetic field the role of frontal parts of windings appears much more essential, than in the conditions of classical AC machines. This is manifested in an increase of 5-6 times the relative contribution to the equation of equilibrium of the EMF and the voltage drops on the reactance of the frontal scattering, as well as on the active resistance of the windings.
3. An important advantage of the loop shortened winding compared to the concentric diametric winding is the shorter length of the frontal part conductor, which reduces the active resistance of the winding as a whole by 11 % and the reactance of the frontal scattering by 18 %.
4. The loop three-phase winding is symmetrical, while the concentric winding has a pronounced asymmetry due to differences in the parameters of its frontal parts, which leads to a significant deterioration of the electromagnetic parameters of the inductor as a whole.
5. Due to the peculiarities of the discrete phase structure of the concentric diametric winding and the asymmetry of its phase currents, the magnetic field in the working chamber of the inductor is unstable and less homogeneous compared to the loop shortened winding.
6. The advantages of the concentric winding include a slightly smaller particle size of the inductor in the area of its frontal parts, as well as less complex technology of manufacturing and laying in the slots of the core.
7. Further development of research should be the development of technology for the manufacture of loop shortened two-layer winding in the inductor conditions, the implementation of its relevant experimental studies, as well as improving the parameters of this winding by optimizing it.
Conflict of interest. The authors declare that they have no conflicts of interest.
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Received 15.05.2021 Accepted 20.06.2021 Published 27.08.2021
V.I. Milykh1, Doctor of Technical Science, Professor, M.G. Tymin1, Postgraduate Student,
1 National Technical University «Kharkiv Polytechnic Institute», 2, Kyrpychova Str., Kharkiv, 61002, Ukraine, e-mail: mvikemkpi@gmail.com (Corresponding author), gunter_odim@ukr.net
How to cite this article:
Milykh V.I., Tymin M.G. A comparative analysis of the parameters of a rotating magnetic field inductor when using concentric and loop windings. Electrical Engineering & Electromechanics, 2021, no. 4, pp. 12-18. doi: https://doi.org/10.20998/2074-272X.2021.4.02.
