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Section 15. Technical science
Abubakirov Azizjan Bazarbaevich, Karakalpak state university, Uzbekistan E-mail: [email protected]
RESEARCH OF THE ELECTROMAGNETIC TRANSDUCERS FOR CONTROL OF CURRENT OF THREE PHASES NETS
Abstract: In the given article it is described the principles values and parameters of combined control of three-phase current of electric nets and power supply systems, on the base of theoretical and experimental research principles of desing electromagnetic transdusers of primary current to secondary voltage with flat measure winding; mathematical models; algorithms of research and designing; methods of calculation, has allowed to solve a problem about development and construction efficient electromagnetic transdusers one- and multiphases primary current to secondary voltage.
Keywords: electromagnetic transdusers, magnetic circuits, measure transdusers, nonsymmetrical parameters, windings, primary current, secondary voltage.
At present employed of electromagnetic transducers of single-phase current with unified output value, expansion of spectrum converting electric values is limited, because of insufficient developer of methods of calculation and research of magnetic transforming circuit of transducers. The classical methods of research of magnetic circuits don't provide necessary accuracy, because three-phases primary currents of electrical nets include asymmetries, which do not possess sufficient generality, covering herewith only main varieties of circuits with electric and magnetic nature. Unfortunately, magnetic circuitries with nonsymmetrical parameters and values of primary current of electric nets calculations has been taken as a object with concentrated parameters [1, 2].
The System analysis of electromagnetic transducers of primary current has allowed also to install, because classical designs of transducers of current - a transformers of current provide on output current by value 5 A in nominate of primary, value have: restriction on range of converted current; significant inaccuracy; complex and non-technological of designs; greater size; mass; specific consumption of materials and cost. Under nominate of input current, require matching element - an additional transformer for unification of joint work with modern microprocessors and controller computers. The Fact just cited limited in use classical electromagnetic transducers of current related to control system
of values and parameter of electric nets. So development, research and practical introducing for electromagnetic transducers with flat measure winding primary one- and three-phases current to secondary voltage with extended functional possibility and unified output value, taking into account nonsymmetricals of three-phase current and creation on their base systems of multifunction control power is a decision of the problem of improvement and developments existing technologies of control values and parameters of electric powers is important and actual problem of power supply systems (PSS).
Constrictions of electromagnetic transducers of the current to voltage with flat measure winding for multifunction control of power sources of PSS are on (fig. 1 and 2).
The technical data of electromagnetic transducers of the current to voltages with flat measuring winding for power course of PSS given in tab.l. On the base of analysis of main correlations of current output voltages electromagnetic transducer to voltage with flat measuring windings is installed that most further research must be directed on development of new principle transformations and sensitivity construction transducers current to three-phase electric nets, providing nonsymmetry, unification of the output values and possessing extended functional possibility for combined control of sources of PSS [3].
1-base - main core, 2, 3 and 4 - gaps, 5, 6 and 7 - seal holder plastins, 8, 9 and 10 - flats measuring windings (FMW), 11, 12 and 13 - insulation plastins, A, B and C - primary windings - conductors of electrical three-phases nets of PSS Figure 1. The Electromagnetic transducers of the primary current to secondary voltage with a fixed magnetic circuit
^J3Gbtxl L 9Sbix2 t-'se&.ixj' t-?gbix4
1 and 2 - base - main cores, 3, 4, 5, 6, 7 and 8 - air clearance, 9, 10, 11 and 12 - gaps,13, 14, 15 and 16- insulation plastins, 17, 18, 19 and 20 - flats measuring windings (FMW), A, B and C - primary windings - conductors of electrical three-phases nets
of PSS
Figure 2. The Electromagnetic transducers of the primary current to secondary with movable magnetic circuit
Table 1.- The technical data of current electromagnetic transdusers
Number of input point Primary current Output voltage U (v) " Coeff. of transformation KT Resistanse R (mn) Inductance Lp (H Construction chemas of connections flate measuring windings (FMW) with advisable numbers of windings
I (A) I max (A)
1 2 3 4 5 6 7 8
1. 25 36 25 1/1000 0.3 0.023 1
2. 12 18 24 2/1000 1.1 0.09 1
1 2 3 4 5 б 7 s
З. 8 12 24 З/1000 2.S 0.21 О-Ov Оч О—О о—oN> >о-о
4. б 9 24 4/1000 4.4 0.З7
S. S 7 2S S/1000 б.З 0.S8 1П кхч^1 Out 6 7 8 9 10
The Analysis of functioning transducers conditions of primary current and requirements have shown that in energy system is advisable to use electromagnetic transducers of current and voltages with flat measuring windings and develop-
ment principle transformations and design electromagnetic transducers, providing account nonsymmetrically, unification of the output values and possessing extended functional possibility for multifunction control source of PSS.
Table 2.- Principle of flat measuring windings design for electromagnetic transducers of primary current to secondary voltage
N
Type of flat measuring windings
Form of flat measuring windings
Area of the section
1.
Triangulare
Str = ab/ 2
Square-wave
S = kab
sq
Round
тл 2
Sr = knD /4
4.
Loopy
S = 2 аb
p
The graphs of the steady-state features of primary current electromagnetic transdusers to secondary voltage, got according to equations (1-3) are presented on (fig. 3-6):
Ueout = 4,44 fW (Fpi
RIt
± F,
) (1)
pio max A
Similar equations for building of steady-state features for secondary voltages of phases B and C three-phase electric nets:
USout = 4,44 fW (Fm
Umut = 4,44 fW (Fm
M LII
± Fr
_ M
Lii
e Li ), (2)
_ RIIIf
e Ll11 ± F
_ RIIIf liii
(З)
As can be seen from fig.3 and 4, when increase air gaps-clearance, strongly decreases the value of the output voltage Uou. The Best output voltage values are provided at value of the air clearance equal to 0.002-0.003 m. and count whorl
WpMW equal to 3-4 (fig.5). Increase the number of the elec- change area sections of flat measure winding provide linear tromagnetic transducers whorl of current to voltage (fig. 6) change output value of the voltage (fig. 6). promotes more fluent change value of the output voltage,
<_„a
e icperimental
calculateid
:t
M
., A
(1-20 mm., 2-22 mm., 3-24 mm., 4-26 m.) Figure 3. Steady-state features of output voltage under different FMW under importances of the air clearance (points - an experiment, line - a design values)
Figure 4. Dependency of the Ueout with different importances
Figure 5. Graphics of output voltage Ue out in different importances of the number whorl - WFMW.
In the graphics (fig. 3-6) shown the results of research, total reliability of design of electromagnetic transducers of current to voltage with flat measure winding forms: R = R =
c o cat par
=0.98 0.98=0.96, where: Rcat - catastrophic reliability, Rpar -parametric reliability fully corresponds to the requirements of combined auto control systems of source of the power of PSS.
For the electromagnetic transducers of current to voltage with flat measure winding for nonsymmetries control electrical nets of three phases of total errors are defined based on fair spuare error windings excitement, magnetite, flat measure windings and measure scheme:
c at a Hal id-.
\
s xperirnentt û
/
u
a™ i io vu
Figure 6. Graphics of output voltage Ueout in different importances area sections
S . = 0.02; S = 0.01; S, = 0.01; S = 0.05.
prim.win ' m ' fmw ' source
The entropy importance of inaccuracy for electromagnetic transducers of current to voltage with flat measure winding for control of nonsymmetry three phases electrical nets is defined by the formula S rans = S2, where: Sz - total importance of inaccuracy of electromagnetic transducers of current to voltage with flat measure winding, equal 0.11; ke - entropy factors, having different importance under different distribution law (for normal law of distribution of inaccuracy ke = 2.07). The Calculation is installed that entropy inaccuracy of electromagnetic transducers of primary current to secondary
voltage with flat measure winding for control of nonsymmetry of three phases electrical nets equal to 8 = 0.11, where experimental dates of evidence 8 = 0.21.
L exp
Conclusion
In the given article it is described a combined control of values and parameters ofthree-phase current ofelectric nets and power PSS, on the base of theoretical and experimental research is designed: principles ofdesign ofelectromagnetic transducers of primary current to secondary voltage with flat measuring winding; the corresponding to mathematical models; the algorithms of research and designing; as well as methods of the calculation that has allowed to solve a problem development and construction efficient electromagnetic transducers one-and multiphase primary current to secondary voltage.
They are in total received following main results:
1. Motivated, that using flat measure windings in electromagnetic transducer, provides control system the reception unified out signal with parameter: voltage - 20 V, current - 100 mA and allows to develop new electromagnetic transducer of current to voltage with flat measuring windings -as detector element, being up to quality of combined control power of PSS.
2. The Best values of out voltages Uout are provided at value of air gaps - clearance -S equal - 0.002-0.003 m and were numbers whorl flat measuring windings - WFMW equal - 3-4.
3. Theoretical value of inaccurate entropy of transducers of current to voltage does not exceed 0.2%, but experimental importance of inaccuracy electromagnetic transducer of the current to voltage with flat measure windings equal to 0.21%.
4. On the basis of calculation is described that, total reliability combined in control system source of PSS on the base of electromagnetic transducer of primary current to secondary voltage with flat measure windings equal to - best value, equal to 0.96.
5. Employ electromagnetic converters of current to voltage in electric sets of systems of power supply more than 20 enterprises shows accuracy and automations of control source of power that, have allowed to reduce the loss of electric powers on 11.26% under normative importance 13.29% (have provided the reduction of the technological consumption to electric powers on 1.13 mlrd. kVt-hour)of account due to increasing the class of accuracy of elements control system of power PSS1.0 to 0.5.
References:
1. Siddikov I. Kh., Khakimov M. Kh., Anarbaev M., Bedritskiy I. M. Research of the electromagnetic transdusers of the primary current to secondary voltage // Science and Education. Materials of the II International Research and practice conference. - Vol. I. Publishing office of «Vela Verlag Waldkraiburg», Munich, Germany, December, 18-19, - 2012.- P. 222-225.
2. Siddikov I. Kh. The Electromagnetic Transducers ofAsymmetry of Three-phases Electrical Currents to Voltage. Universal Journal of Electrical and Electronic Engineering. Horizon Research Publishing Corporation USA. - 2015. - Vol. 3. -No. 5.- P. 146-148.
3. Siddikov I. Kh. The construction of the transducers of current to voltage with flat measuring windings for combined control of power of the energy systems. "American Journal of Science and Technologies" Princeton University Press, USA, - No. 2 (20). (July - December), - 2015. - P. 614-621. Impact Factor - 2015: 6.391.
4. Siddikov I. Kh., Sattarov Kh.A., Khuj amatov Kh. E. Research of the Influence of Nonlinear Primary Magnetization Curves of Magnetic Circuits of Electromagnetic Transducers of the Three-phases Current. Universal Journal of Electrical and Electronic Engineering. Horizon Research Publishing Corporation USA. - 2016. - Vol. 4. - No. 1. - P. 29-32.
