-
Performance and analysis of 3 phaseinduction motor using Ansys
Maxwell
Anagha Soman1, Nupur Lokhande2
and Dr. D G Bhardwaj31Asst. Professor,
Bharati Vidyapeeth Deemed University,COE Pune
[email protected] Student,
Bharati Vidyapeeth Deemed University,COE Pune
[email protected]
January 9, 2018
Abstract
It is evident that an induction motor is very reliable, ro-bust
and efficient machine used for various industrial appli-cations
under various loading conditions. Induction motorsare cheaper in
cost, rugged in construction and require verylittle maintenance.
This paper focuses on performance as-pects and censorious fields in
the design of such a machine.A laboratory precursor of three phase
double stator induc-tion motor (DSIM) is drafted and contrived to
delve intoassorted facets. Induction machines with a two
dissimilarpole stator windings have been put to effective use since
itfunctions well in the power fields. Since they have dimin-ished
pulsation when the torque is lesser. Three phase sup-ply with
variable frequency is fed to the two stator windingsof DSIM which
proves out to be very expedient. Throughthis, not only the torque
pulsations are reduced consider-ably, but increased commutation
frequency is also achieved
1
International Journal of Pure and Applied MathematicsVolume 118
No. 16 2018, 269-281ISSN: 1311-8080 (printed version); ISSN:
1314-3395 (on-line version)url: http://www.ijpam.euSpecial Issue
ijpam.eu
269
-
as compared to simple machines. The analysis of this ma-chine is
executed employing FINITE ELEMENT METHODat steady state level.
Analysis has been carried out for 4-pole and 12-pole motor; their
behaviour has been studiedand compared. The tools used for this
analysis are AN-SYS Maxwell 2D and RMxprt. RMxprt is instrumental
innot only giving classical motor performance parameters, butalso
spawns an outright transfer of the 3D or 2D geometryin conjunction
with all electrical as well as electromagneticproperties. The
conclusions retrieved are conferred and pre-sumptions are
drawn.
Key Words and Phrases: Induction motor, perfor-mance, analysis,
finite element method, RMxprt, Maxwell2D, Ansys
1 Introduction
The performance analysis of a dual stator winding induction
drivehas been described and studied in this paper. The
contemplatedinduction machine consists of a standard squirrel cage
motor withtwo separate windings wound for a dissimilar number of
poles. Thecontemplated drive bids advantages like speed sensor less
opera-tion, improved reliability, and more flexibility to
manipulate theresultant torque-speed curve of the motor.
There are two major types of dual stator machines which
aresplit-wound and self-cascaded. The split-wound machine was
pop-ularized in earlier times as a begetter to increase the total
powercapability of large synchronous generators [1]. Ever since
then,they have been used in various other applications ranging from
syn-chronous machines to large pumps and compressors.
Split-woundmotors are responsible for making it conceivable to
prolong thepower spectrum of solid state based drives beyond the
power com-petence of a lone inverter and more freshly, new
multilevel topolo-gies have also been developed [2]. Also, at the
hand of the implicitrepetition, it is asserted that the system
exhibits a superior authen-ticity [3][4][5]. In a split-wound
machine, the stator comprises oftwo complementary but independent
three-phase windings woundfor the like number of poles. Both
stators are provided with thesame frequency and the rotor is a
standard squirrel cage.
2
International Journal of Pure and Applied Mathematics Special
Issue
270
-
Among the various multiphase drive solutions, one of the
mostalluring and widely practised is the dual stator winding
squirrel cageinduction motor. The dual stator induction motor has
two separatethree-phase stator windings, partaking the same machine
core andcommon squirrel cage rotor winding. In this paper, the
analysis of4-pole and 12-pole induction motor has also been
studied.
2 Dual Stator IM Drive
The prospective induction machine comprises of a classic die
castsquirrel cage rotor and a stator with two independent
windingswound for a diverse number of poles (4/12). Any sequence of
dis-similar pole numbers can be used, but to optimize the
magneticmaterial, avoid local saturation and more stator losses, it
has beenobserved that the most beneficial arrangement should have a
poleratio 1:3.
Figure 1: Dual Stator Induction Motor
In order to dodge deep saturation, the maximum magnetic load-ing
created by the mixed aftermath of the two stator mmfs shouldbe
analogous to that of an equivalent single stator winding
con-struction. To retain the saturation level in the stator teeth,
thepeak air gap flux must be preserved. Also, to retain the
loadingof the stator yoke the peak flux density per pole should be
inter-changeable in both the dual stator and single stator
construcions.
3
International Journal of Pure and Applied Mathematics Special
Issue
271
-
Omitting space harmonics, this will be consummated by culling
[6]
Bg4 = 0.819B0
Bg12 = 0.543B0 (1)
where B0, Bg4 and Bg12 represent the maximum air gap
fluxdensities created by a proportionate single stator, the 4-pole
and12-pole stator windings correspondingly. The rotor of the DSIMis
classic squirrel cage, which makes sure that both stator
currentdistributions will concurrently couple with the rotor flux
to createthe aimed torque. Due to the decoupling reaction composed
bywindings with dissimilar number of poles the DSIM acts as
twoautonomous induction machines mechanically coupled using
shaft.For our machine, general assumptions have been taken into
consid-eration which is as under:
• Trivial saturation
• Homogeneous air gap
• Stator windings sinusoidally dispersed
• No electrical linkage among stators
• Trivial inter-bar current
3 Maxwell 2D and Ansys
ANSYS Maxwell is the economic electromagnetic field
simulationsoftware for designers who are engaged for fabricating
and analysing3-D and 2-D electromagnetic and electromechanical
equipment, whichincludes motors, actuators, transformers, sensors
and coils. Maxwell2D is a great-performance bilateral program kit
that puts to use thefinite element analysis (FEA) to determine
electric, magneto static,eddy current, and transient problems.
Maxwell 2D determines theelectromagnetic field problems for a given
model with pertinent ma-terials, boundaries and source conditions
applying Maxwell’s equa-tions over a finite region of space
[7-9].
Differential forms of Maxwells equations are as follows:
4
International Journal of Pure and Applied Mathematics Special
Issue
272
-
3.1 FEM and Adaptive Meshing
With an aim to glean the set of algebraic equations which we
needto solve, the geometry of the problem is discretized on its own
intoinfinitesimal elements (e.g. Triangles in 2D). All the model
solidswill be meshed on its own by the mesher. The aggregation of
alltriangles is said to be the finite element mesh of the model or
merelythe mesh.
3.2 RMxprt
Engineers who design electrical machines and generators now
havethe advantage to augment ANSYS Maxwell with ANSYS RMxprt,a
template-based design tool. Together Maxwell and RMxprt havebeen
successful to make a truly tailor-made machine design flow inorder
to cater to the market demand for surpassing efficiency andlower
cost machines. Putting to use the classical analytical motortheory
and equivalent magnetic circuit methods, RMxprt can calcu-late
machine performance, make initial sizing decisions and
performhundreds of ”what if” analyses in a matter of seconds. A key
as-set of RMxprt is that it is capable of automatically setting up
anentire Maxwell project (2-D/3-D) which can also include
geometry,materials as well as boundary conditions. The set up
includes thepertinent symmetries and excitations with coupling
circuit topol-ogy for meticulous electromagnetic transient
analysis. RMxprt au-tomatically generates a reduced order model,
considering the non-linearities and eddy effects, and transmits it
to Simplorer, wherefurther electric drive analysis can be achieved.
Likewise, RMxprtcan successfully set up the tilor-made driving
circuit topology as astand-alone component in Simplorer which can
be coupled with thecorresponding electric machine reduced order
model.
5
International Journal of Pure and Applied Mathematics Special
Issue
273
-
4 Squirrel Cage motor design using RMx-
prt
Most commonly AC motors use squirrel cage rotor. The
motoremblematically cast aluminium or copper poured between the
ironlaminates of the rotor. The considerable fragment of the
rotorcurrents flow through the bars and varnished laminates.
UsingRMxprt, a 1.3 kW three phase squirrel cage induction motor
isdesigned and analysed. The material assigned for laminated
steelsof rotor and stator is 50C350. The windings allotted are
copper.The user interface for a 4-pole RMxprt is shown in Fig.
2.
Figure 2: RMxprt User Interface (4-pole)
Since the RMxprt is a template based tool, the time requisitefor
analysis is in order of seconds. The results are shown in
Table1.
Table 1. RMxprt Results (4-pole)
Similarly, the design of 12-pole motor is also carried out
using
6
International Journal of Pure and Applied Mathematics Special
Issue
274
-
RMxprt as follows. The material assigned for laminated steels
ofrotor and stator is 50C350. The windings allotted are copper.
Theuser interface for a 12-pole RMxprt is shown in Fig. 3.
Figure 3: RMxprt User Interface (12-pole)
Since the RMxprt is a template based tool, the time requisitefor
analysis is in order of seconds. The results are shown in
Table2.
Table 2. RMxprt Results (12-pole)
5 Squirrel cage motor design using Maxwell
The motor specified above is relocated from RMxprt to
Maxwellwith a direct channel. Maxwell uses the accurate finite
elementmethod to determine static, frequency-domain, and time
varyingelectromagnetic and electric fields. The parameters of the
motorare same, as shown in Table 1 and 2 for 4 and 12-pole
respectively.
7
International Journal of Pure and Applied Mathematics Special
Issue
275
-
The automatic flexible meshing technique of Maxwell-2D is
usedfor meshing.
As a result of analysis, the magnetic flux density during
themaximum current, the current vs time, torque vs time and
graphicsfor the defined motor with 4-pole are obtained and
presented at Fig.5 (a), (b), and (c) respectively.
Figure 5(a): Magnetic flux density
Figure 5(b): Phase current vs Time
8
International Journal of Pure and Applied Mathematics Special
Issue
276
-
Figure 5(c): Torque vs Time
Similarly the magnetic flux density during the maximum cur-rent,
the current vs time, torque vs time and graphics for the
definedmotor with 12-pole are obtained and presented at Fig. 6 (a),
(b),and (c) respectively.
Figure 6(a): Magnetic flux density
Figure 6(b): Phase current vs Time
9
International Journal of Pure and Applied Mathematics Special
Issue
277
-
Figure 6(c): Torque vs Time
Speaking about the dual stator three phase induction motor,the
torque vs. time for dual stator winding can be found in
Fig.7(a).
Figure 7(a): Torque vs. Time (Dual Stator)
Similarly, the power vs. time results for dual stator
windingthree phase induction motor can be observed in Fig.
7(b).
Figure 7(b): Powers vs. Time (Dual Stator)
It is observed here that the moving torque by dual stator
wind-ing induction motor is more as compared to 4-pole single
statorwinding induction motor.
10
International Journal of Pure and Applied Mathematics Special
Issue
278
-
We also observe that the powers in dual stator winding
stabilisesfaster as compared to the 4-pole single stator winding
inductionmotor.
6 Conclusion
In this paper, ANSYS Maxwell 2D and RMxprt software tools
areused to create a squirrel cage motor design and to analyse it.
Themotor parameters and characteristics can be precisely
calculatedand predicted in terms of field computation and analysis
results.Also it is seen that by developing the computer technology
and in-creasing computing times, the FEM tools are becoming more
ben-eficial to analyse the motor. The proposed DSIM has a
standardsquirrel cage rotor and two stator windings wound for a
dissimilarnumber of poles. The main benefit of the drive is its
better capabil-ity to operate. This trait is particularly useful
for implementationof speed sensor less schemes and it adds a new
degree of flexibilityto standard control methods currently used in
AC drives. We havealso seen in this paper how the torque and power
curves of singlestator and dual stator winding induction motor
varies.
References
[1] P. L. Alger, E. H. Freiburghouse and D. D. Chase,
Doublewindings for turbine alternators,AIEETransactions, Vol.
49,January 1930, pp. 226-244.
[2] R. W. Menzies, P. Steimer, and J. K. Steinke, Five-level
GTOinverters for large induction motor drives, IEEE Transactionson
Industry Applications, Vol.30, No.4, July/August 1994,
pp.938944.
[3] R. W. Menzies, P. Steimer, and J. K. Steinke, Five-level
GTOinverters for large induction motor drives, IEEE Transactionson
Industry Applications, Vol.30, No.4, July/August 1994,
pp.938944.
[4] J. R. Fu and T. A. Lipo, Disturbance fr ee op eration of
amultiphase current regulated motor drive with an opened phase,
11
International Journal of Pure and Applied Mathematics Special
Issue
279
-
IEEE Transactions on Industry Applications, Vol. 30, No.
5,September/October 1994, pp. 1267-1274
[5] J. C. Salmon and B. W. Williams, A split-wound
inductionmotor design to improve the reliability of PWM inverter
drives,IEEE Transactions on Industry Applications, Vol. IA-26,
No.1, January/February 1990, pp. 143-150
[6] A. R. Mu noz-Garca, Analysis and control of a dual
statorwinding squirrel cage induction machine, Ph.D.
Dissertation,University of Wisconsin-Madison, 1999.
[7] Zhou Rui; Wang Qunjing; Li Guoli; Pang Cong; FangGuanghui,
Optimal design of single-phase induction motorbased on MAXWELL 2D
Rmxprt, Electrical Machines and Sys-tems (ICEMS), 2010
International Conference on , vol., no.,pp.1367,1370, 10-13 Oct.
2010
[8] Qiu Changli; Cheng Jihang; Li Jingquan, Simulation
analysisof the performance of linear introduction motor in Maxwell
2D,Electrical & Electronics Engineering (EEESYM), 2012
IEEESymposium on , vol., no., pp.360,363, 24-27 June 2012
[9] Mei-shan Jin; A-lin Hou; Chang-li Qiu; Da-chuan Chen,
AMaxwell 2D emulated analysis in the performance of linear
in-troduction motor, Computer, Mechatronics, Control and
Elec-tronic Engineering (CMCE), 2010 International Conference on,
vol.4, no., pp.348,351, 24-26 Aug. 2010
12
International Journal of Pure and Applied Mathematics Special
Issue
280
-
281
-
282