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Computer-Aided Teaching Using MATLAB/Simulink for Enhancing an IM Course With Laboratory Tests Amar Bentounsi, Hind Djeghloud, Hocine Benalla, Tahar Birem, and Hamza Amiar
Abstract—This paper describes an automatic procedure using MATLAB software to plot the circle diagram for two induction motors (IMs), with wound and squirrel-cage rotors, from no-load and blocked-rotor tests. The advantage of this approach is that it avoids the need for a direct load test in predetermining the IM characteristics under reduced power. Additionally, to verify the validity of the equivalent circuit parameters deduced from experimental tests, these characteristics are used to simulate virtual machines implemented under Simulink/PSB models. Furthermore, a virtual load test is performed to validate the proposed model. Finally, the results are given of an assessment that reflects the positive impact the proposed methods have had on students’ learning experience in electrical machinery courses in the Electrotechnics Department, Engineer Sciences Faculty, University Mentouri of Constantine (ED-ESF-UMC), Algeria.
Rotor leakage reactance referred to stator. Coefficient of total leakage. Stator resistance. Rotor resistance. Rotor resistance referred to stator. Equivalent core losses resistance. Inertia moment. Viscous friction coefficient. Slip.
Index Terms—Characteristics, circle diagram, experimental tests, induction motor, MATLAB/Simulink, virtual tests.
SUPERSCRIPT Rotor quantities referred to stator. SUBSCRIPTS
LIST OF SYMBOLS
Stator quantities, rotor quantities. No-load test measures, blocked-rotor test measures.
Line-to-neutral point voltage. Line-to-line voltage. Stator linkage inductance.
I. INTRODUCTION
Stator leakage inductance. Magnetizing inductance. Stator/rotor nominal voltage ratio. Rotor linkage inductance. Rotor linkage inductance referred to stator. Rotor leakage inductance. Rotor leakage inductance referred to stator. Magnetizing reactance. Stator leakage reactance.
Manuscript received January 08, 2010; revised June 14, 2010; accepted August 29, 2010. Date of publication October 28, 2010; date of current version August 03, 2011. The authors are with the Laboratory Electrotechnics of Constantine, Engineer Sciences Faculty, Ahmed Hammani Campus, University Mentouri of Constantine, Constantine 25000, Algeria (e-mail:
[email protected]). Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TE.2010.2085046
NTERACTIVE learning with multimedia tools is increasingly popular in education because of its advantages in terms of innovative pedagogy and its positive impact on student outcomes. In this area, low-cost personal computers and a variety of software packages have led to the concept of “computer-aided teaching or learning.” This modern didactic contributed in particular to the good understanding and management of the credit hours of theoretical courses and laboratory experiments [1]–[6]. The undergraduate electrical engineering schedule of the Faculty of Engineer Sciences of Mentouri University (ED-ESF-UMC), Constantine, Algeria, consists of several modules. In the Electrical Machines curriculum, the induction motor (IM) is given much attention because of its multiple advantages. In the module on symmetrical 3-phase ac machines in steady-state operation, which is taught to third-year academic graduate degree (ELT2) students and to fourth-year engineering (T423) students, the IM is introduced in terms of its theoretic principles and operating characteristics; this treatment includes the concepts of magnetic coupling, rotating field, induction phenomena, basic equations leading to the equivalent circuit, circle diagram, and so on. The classroom is enhanced by a laboratory section where the students carry out two series
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of experimental tests: 1) dc test and no-load and blocked-rotor tests to evaluate the parameters of the IM equivalent circuit and to draw the circle diagram, making it possible to deduce the IM characteristics; and 2) a load test with a dc generator to find these characteristics directly [7]. Finally, the students must compare the results of the indirect and direct tests to check the accuracy of the equivalent circuit model by using the circle diagram. The indirect approach to predetermining the IM characteristics is very interesting because it involves reduced power (losses), unlike a direct load test. To facilitate the transition from the laboratory tests to drawing the circle, the procedure was automated via a user-friendly program written in the MATLAB environment [8]. This saves time and gives better accuracy. Additionally, the parameters of the equivalent circuit were used to simulate the previous three experimental tests of the IM by means of virtual machines, constructed using Simulink/PSB. In comparison to [1], the originality here relates , representing the iron losses, and to the inserted resistance the load test performed by coupling a dc generator to the IM [8]. The paper is organized as follows. Section II covers the basic theory of IM. Section III describes the dc test, no-load and blocked-rotor tests, and also the evaluation of equivalent circuit parameters. Section IV explains the automated drawing of the circle diagram and its use. Section V presents the Simulink/PSB models and provides comparative studies between virtual and practical results. Section VI analyzes the teaching impact of the proposed pedagogy. II. BASIC THEORY OF INDUCTION MOTOR Like any conventional electrical machine, the IM has two active elements (two three-phase balanced windings), a stator and a rotor, which interact via an air gap where the energy exchanges take place. In normal operation, the stator is excited by alternating voltage. This creates a rotating magnetic field inducing currents in the rotor winding. These currents, in turn, interact with the rotating field to produce torque. Under some assumptions regarding the operation (balanced currents, unsaturated circuits, and so on), the stator and rotor fluxes can be calculated. Because of the symmetry of the balanced three-phase IM stator and rotor windings, it is sufficient to take only one phase into account. Each phase has a resistance in series with a linkage inductance , and the windings are magnetically coupled through a mutual inductance . Since the frequency of stator currents is , the frequency of the currents induced in the . Accordingly, the voltage rotor winding is equal to and current equations for the stator (primary) and rotor (secondary) are expressed as follows: (1) (2) (3) are respectively the stator, the rotor rewhere , , and ferred to the stator, and the magnetizing currents. can be To take into account the iron losses, a resistance . As there added in parallel with the magnetizing reactance is an analogy between the IM and the transformer, the per-phase
Fig. 1. Per-phase equivalent circuit of an IM.
TABLE I SPECIFICATIONS OF TESTED MOTORS
equivalent T-diagram referred to the stator of the IM is depicted in Fig. 1. With this equivalent circuit, the operational performances of an IM can be completely described. In normal operation, this diagram is used with constant voltage and frequency, therefore with a constant flux linkage. III. EXPERIMENTAL TESTS AND EQUIVALENT CIRCUIT PARAMETERS The per-phase equivalent scheme parameters [9]–[12] can be determined using hardware experiments. These experimental tests are done on two types of Y-connected 4-poles IMs: a (DL 2052 of De Lorenzo) and a squirrel-cage wound motor motor (TE 100 LR4 of Ecodime) whose specifications are given in Table I. The experimental dc test and no-load and blocked-rotor tests are described here, which are easy for students to perform to determine the parameters of a previous equivalent electric model [7]. Skin, temperature, and saturation effects are not taken into consideration here since this work is directed toward the teaching of undergraduate electrical engineering students. These effects should, of course, be taken into account in advanced courses for graduate-level students or in actual research [13]–[15]. A. DC Test The dc test provides data allowing the calculation of the stator and rotor resistances. By feeding the stator and rotor windings successively under dc voltage, the volt-am-metric method of resistances calculation was applied for various currents until the nominal intensity gave the following average values: : and ; • : . • B. No-Load Test The no-load test is performed to determine the equivalent parameters of an IM (Fig. 2). From this test, the parameters and and the rotational losses can be found. The data acis the stator copper quired are reported in Table II, where is the core losses, and is the mechanical losses losses, from friction and windage. After acquisition of this data, the
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Fig. 2. No-load test: (a) experimental bench and (b) equivalent scheme.
Fig. 3. Separation of core and mechanical losses: (a) for Motor 1; (b) for Motor 2.
Fig. 4. Saturation characteristic represented by Lm versus V curve of (a) M 1 and (b) M 2.
MATLAB commands Polyfit, Linspace, and Polyval used to obtain the best line passing through the maximum of points as shown in Fig. 3. The intersection of these curves with the y-axis gives the following mechanical loss values: : W; • • : W. According to Fig. 2(b) (4) and
C. Blocked-Rotor Test The experimental setup of the locked-rotor test is similar to that of the no-load test shown in Fig. 2(a), but in this case, the rotor is hand-blocked (the slip is unity) and a reduced voltage is applied to the stator terminals to avoid exceeding the rated to be found. Since current. This test allows the resistance the rotor current is much larger than the magnetizing current, the excitation branch can be neglected. The resulting equivalent circuit for this test is shown in Fig. 5, from which the absorbed active power can be deduced
(5) versus the voltage Fig. 4 plots the magnetizing inductance . These curves give information about the magnetic characdecreases when saturation increases. teristics and show that Then, from Table II, the average values are calculated in the vicinity of the saturation knee of the magnetizing curve: : , , ; • : , , . •
(6) as well as the equivalent impedance
(7) The measurement data (Table III) allows the approximate computation of the parameters:
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TABLE II RESULTS OF NO-LOAD TESTS
TABLE III RESULTS OF BLOCKED-ROTOR TESTS
( )
P
=
P 3 (U =U
) ,
I
=
I 3 (U =U
).
Fig. 6. Separate measurement of leakage reactance. (a) Measurement of X . (b) Measurement of X .
Fig. 5. Equivalent circuit of blocked-rotor test.
•
:
,
D. Method for Separation of the Leakage Reactance , one phase of the stator is fed with • To determine of to avoid core saturation, and the line current and the absorbed active power are measured
,
; : , . • , the value of obtained from the equivaIn the case of lent circuit of Fig. 5 induces an error of 18% since the measured is 0.86 (dc test). This rate is quite high; in order value of to minimize it, the magnetizing branch, which is neglected in most studies dealing with the blocked-rotor test, is taken into account. This approach is justified because the magnetizing current value is not negligible (3.25 A) if compared with the nomcan inal value (8 A), and should thus be taken into account. then be evaluated as (8) where
(9) an error of . Then, Various standards exist for specifying the operating and constructional parameters of the electric motors. Commonly used are those of the National Electrical Manufacturers Association (NEMA) and the International Electrotechnical Commission (IEC). NEMA standards specify five design types: A, B, C, D, and E. When the classification of the motor is . In this case, it can be not known, it is assumed that deduced: : ; • : •
Then, both reactive power and voltage are calculated in the terminals [Fig. 6(a)] to determine the cyclic reactance
The following can be deduced: , . • To determine of , two phases of the rotor are fed , and the line current and the absorbed with active power are measured: , , . Then, both the reactive power and current of are calculated [Fig. 6(b)]
As this method is not applicable for the squirrel-cage motor , the way in which to determine the leakage reactance indirectly from the circle diagram will be discussed. E. Deceleration Test In order to determine and , an indirect method that consists of using a dc machine functioning initially as a generator with separate excitation driven by the IM, then operating as a no-load motor, is used. By simply subtracting the results
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Fig. 8. Approximated per-phase equivalent circuit of an IM.
Fig. 7. Deceleration curve.
of the two tests, this gives and of the IM. The deceleration curve shown in Fig. 7 makes it possible to visualize, on a digital oscilloscope using Hameg Instruments’ software SP107, the time-varying electromotive force (EMF), proportional to the (proportionality factor ), from the initial moment speed until the final stop. For where the EMF value is a dc generator coupled to the IM, the following equation can be deduced from the kinetic energy of the rotating system:
Fig. 9. Circle diagram.
(10) Knowing that (11) in the case of viscous friction, one deduces that (12) (13) is the deceleration time. Then, : • : kg.m , • : kg.m ,
Since is perpendicular to , the locus of the rotor is an arc of a circle of diameter , current when the slip varies from zero (at synchronous speed) ad infinitum (the ideal short circuit). Thereby, it is easy to prove that the locus of the stator current is the same arc of circle (but at different origins, and ) because of the relation (3) and knowing that the magnetizing is constant (Fig. 9). Its layout will now be briefly current indicated from the blocked-rotor and no-load tests. This procedure was automated within the MATLAB environment.
and N.m.s/rad; N.m.s/rad.
IV. CIRCLE DIAGRAM AND CHARACTERISTICS OF IM USING MATLAB PROGRAM The circle diagram for asynchronous motors was developed by the German engineers Heyland, Behrend, and Heubach. From their work, various types of more or less accurate diagrams were deduced [10], [12], [16]. The circle diagram of an (or equivalent admitIM is the locus of the stator current tance) when the load varies (i.e., the slip). At ED-ESF-UMC, students are given an approximated diagram deduced from the is equivalent circuit (Fig. 1) where the stator impedance transferred to the right of the magnetizing branch, which is then (Fig. 8). This diagram takes into supplied by the voltage account the iron losses, unlike in the work of Poloujadoff [16], which constitutes an important additional feature. This gives the following relations: (14) (15) (16)
A. Automatic Plotting of Circle Diagram Within MATLAB The flowchart given in Fig. 20 of the Appendix summarizes the steps followed when programming the automated plotting of the circle diagram [8], where is the synchronous point, is the rotor copper losses, and is the mechanical power. The theoretical plotting of the circle diagram is illustrated in Fig. 9. Fig. 10 shows the automated plotting of both motors’ ( and ) circle diagrams, considering the given nominal values. and mechanical power line Note that the loss line are very close. This is due to the very low values of mechanical losses compared to the other power values. To exploit the program developed within MATLAB, the user enters a value for the input power , and then s/he will obtain the results given in Table IV. B. Usual Characteristics of an IM The mechanical characteristic can be deduced either from the circle diagram or from the following analytical formula: (17)
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Fig. 10. Automated circle diagrams of (a)
M 1 and (b) M 2.
TABLE IV RESULTS OF THE SIMULATED CIRCLE DIAGRAM
However, it has a large impact on the slip value for which this maximum is obtained. C. Effects of Different Control Modes
Fig. 11(a) illustrates both experimental and analytical curves representing the electromagnetic torque versus slip for the two and . It can be observed that the experimental motors, curve (deduced from the circle diagram of Fig. 9 using the for) and the analytical curve [obmula tained from (17)] are much too close. The torque is null at the . When increases, increases until a maxslip point imum, then decreases until the starting torque. Fig. 11(b) shows the variations of the stator current versus developed on the motor shaft. The the mechanical power increases from the no-load current tostator current ward the current corresponding to . Fig. 11(c) gives information about the speed , which apfor null slips, then decreases when inproximately equals creases. This figure indicates that the speed variation band is very narrow. Fig. 11(d) depicts the power factor versus the mechanical power. The power factor is weak at the point of zero slip, then increases with and passes by the maximum value (vector tangential to the circle), then decreases with the slip rise. Fig. 11(e) gives the efficiency versus the mechanical power. At the starting point, the efficiency is null, then increases with to a maximum value corresponding to 65%–85% of the full load, then decreases slightly. Fig. 11(f) shows that the rotor resistance referred to stator has no effect on the electromagnetic torque maximum value.
The voltage is adjusted, and then its effect is studied on the speed and the circle diagram. According to Fig. 12(a), if the frequency is maintained at a constant value and the feeding voltage is varied, it can be seen that a reduction of 30% in the voltage induces a reduction of 50% in the torque; this value can be theoretically verified. In starting, the IM is equivalent to a transformer in short-circuit; if connected to the full supply voltage, it produces a locked rotor torque (LRT). Consequently, the motor does not start if the LRT is lower than the load torque, which occurs for weak voltages. In addition, if the load torque is higher than the maximum torque, the motor takes down. To avoid this situation, the designer must define a stability coef. Fig. 12(b) indicates that for a given ficient: frequency Hz , the current diagram is modified in the voltage ratio. Consequently, the power and the electromagnetic torque are proportional to the square of the voltage. For a variable frequency, they are proportional to the square of the flux. D. Determination of
Leakage Reactance
Knowing (from Table IV, ), the leakage reaccan be determined as follows: tance of
Then, ,
; thus, .
V. IM TESTS USING SIMULINK/PSB MODELS In this section, the parameters identified practically in the previous sections will be validated using virtual machines from the Simulink Power System Block Set Library [1], [8]. These machines were dimensioned using the identified parameters, shown in Table V. It should be mentioned here that the core resistance must be taken into account (by inserting three identical resisin parallel to the stator phases), otherwise all results tances will be erroneous. However, if the frequency is variable, core will vary accordingly [14]. losses and the resistance
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M
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M
Fig. 11. Usual characteristics of an IM ( 1 and 2). (a) Electromagnetic torque versus slip. (b) Stator current versus P u output power. (c) Speed versus P u output power. (d) Power factor versus P u output power. (e) Efficiency versus P u output power. (f) Effect of the rotor resistance on the speed-slip curve.
Fig. 12. Effect of different mode control on the speed and the circle diagram. (a) Effect of statoric voltage on the torque-slip characteristic. (b) Effect of statoric voltage on the circle diagram.
A. Virtual DC Test To perform the dc test, the models shown in Fig. 13 are built. From Fig. 13(a), the stator resistance can be measured, and the rotor resistance referred to the stator can be taken from the model of Fig. 13(b). The resistances obtained are as follows: : , , ; • • : .
B. Virtual No-Load Test The virtual no-load test can be carried out using the model of Fig. 14 (the same model was considered for the squirrel-cage motor). The results are given in Table VI. After acquiring this data, and using the commands Polyfit, Linspace, and Polyval of MATLAB, the curves shown in Fig. 15 are obtained. Then: : W (while 80.08 W with • experiments),
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Fig. 13. Measurement of stator and rotor resistances of an IM using Simulink models. (a) Measurement of stator resistance. (b) Measurement of rotor resistance referred to stator.
Fig. 14. Simulink model of the no-load test (case of the wound rotor motor
M 1).
TABLE V SIMULINK VIRTUAL TESTS PARAMETERS
The experimental results from Table II and the simulated results in Table VI can be seen to be much closer, as illustrated in Fig. 15.
C. Virtual Blocked-Rotor Test
•
: experiments).
W (while 11.85 W with
To realize the blocked-rotor test virtually within a Simulink model, the no-load test model is used, and the inertia and the friction parameters are reset to infinite values (here, these parameters were set at 10 000 kg.m and 10 000 N.m.s/rad). Also, reduced voltage values are used. The data obtained, shown in Table VII, clearly agrees with that of experiment analysis.
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Fig. 15. Core and mechanical losses obtained from experiments and simulation (a) for Motor 1 and (b) for Motor 2.
Fig. 16. Simulink model of the load test (case of the wound rotor motor
M 1).
TABLE VI RESULTS OF VIRTUAL NO-LOAD TESTS
D. Virtual Load Test In order to close the loop between experimental and virtual simulated tests, a load test model was established. The complete model is depicted in Fig. 16. The aim is to obtain an absorbed
TABLE VII RESULTS OF VIRTUAL BLOCKED-ROTOR TESTS
stator current belonging to the circle diagram of the considered motor. In this test, the motors are supplied by a three-phase system of balanced voltages with the nominal frequency. The motors are driving dc generators debiting on a resistive load of 10 . The dc generators are separately excited, with field connections (F+, F-) and the armature circuit (A+, A-), consisting of an inductor and a resistor in series with an electromotive force, whose parameters are the following:
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Fig. 17. Validation of virtual tests using the automated circle diagrams of (a)
M 1 and (b) M 2.
Fig. 18. Survey results from the students.
TABLE VIII RESULTS OF VIRTUAL LOAD TESTS
•
coupled with
: V, 240 , , 0.01 H, 180 V; coupled with : V, 240 , • , 0.03 H, 180 V. The results are shown in Table VIII. To validate the load tests, the active power values are entered in the MATLAB program of Section III-A (flowchart given in Fig. 20 of the Appendix). The validation gave the following: : W A (Simulink: • A) : W A (Simulink: • A). The tests are valid since the absorbed currents belong to the circle periphery as demonstrated in Fig. 17. VI. IMPACT ANALYSIS OF THE PROPOSED METHODS The methods proposed in this paper were developed in the context of creating a final-year project for Diploma of Applied University Studies (DAUS) students and for engineering students in the Electrotechnics Department. The work began in the second semester of 2008 with two DAUS students [7]. Their
task was to carry out a practical parametric identification of two kinds of induction motors: wound and squirrel-cage motors. Moreover, they were asked to operate the two machines in the self-excited generator mode; they achieved this with the squirrel-cage machine, but not with the wound one, due to time constraints. In the second semester of 2009, two engineering students [8] resumed the work. Their objectives were to validate the identified parameters through an automatic drawing of the circle diagram, and the implementation of these parameters in virtual machines models, to be performed within MATLAB/ Simulink. All these objectives were successfully attained, and the students acquired a great deal of knowledge of the theoretical and experimental operation of induction motors. In the second semester of 2010, another pair of engineering students worked on the same approach applied to a single-phase transformer. The students found the way well prepared to accomplish their goals. Furthermore, in order to verify the impact of the proposed methods on graduate student’ comprehension, the MATLAB programs established for power-loss separation and the drawing of the circle diagram of the wound IM considered in Section III were introduced in the final laboratory practical of the electrical machines course ELT1, given to second-year graduate-degree students. The students, having some knowledge of IM theory, were delighted to be able to draw their graphs directly from the programs, without using the traditional tools of pencil, compass, ruler, and graph paper. The proposed method is scheduled to be implemented in 2011 for graduate students of the third-year electrical machines course ELT2 and of the fourth-year engineering degree course. Meanwhile, a five-item questionnaire was circulated to each student, which consisted of the following questions.
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Fig. 19. Synoptic scheme of the proposed study.
Q1) Select your preference for the presentation of electrical machinery courses: a) A traditional presentation (using the blackboard)? b) A multimedia presentation? c) A mixed presentation? Q2) Is the circle diagram: a) Difficult to understand? b) Difficult to draw? c) Difficult in both senses? d) Easy to understand and draw? Q3) Do you prefer to draw the circle diagram: a) Manually (with compass and ruler)? b) Automatically (using M-file programming)? Q4) Do you agree that virtual laboratory tests (using MATLAB/Simulink) should precede the experimental practicals? a) Yes b) No Q5) Do you think that it is helpful to use computer skills to check the results of your exercises during the supervised practical work (with tools such as MATLAB/Simulink)? a) Yes b) No The student’ responses are reported in Fig. 18. Globally, the impact of the proposed methods on students’ feedback was very positive. In addition, the circle diagram is a powerful graphic tool [17]–[20]. It takes about 90 min to lay this out manually, and then use it to predetermine the characteristics of the IM. The automated procedure suggested here allows this to be reduced to 30 min and to improve its precision. Moreover, the use of multimedia tools (DataShow and PowerPoint) had a very positive impact on the interest level of the course.
VII. CONCLUSION AND PROSPECTS The use of computer tools for modeling and simulating the operation of the electrical machines is an essential pedagogic complement to modern teaching. The study developed in this paper is an important contribution in the educational domain for the students and lecturers of the Electrical Engineering Department of Mentouri University. The authors’ experience in teaching electrical machines, such as induction motors, shows that students have some difficulties in carrying out their laboratory experiments properly. To overcome this, the authors propose a pedagogic approach based on the use of the MATLAB/Simulink software to predetermine the usual steady-state characteristics of two asynchronous motors (wound ” and squirrel-cage “ ”) starting from three easy-to-per“ form tests (dc test and no-load and blocked-rotor tests). This approach is very useful because it involves reduced powers, unlike a direct load test, which is difficult to implement with powerful machines. A first step consists of entering the test results into a MATLAB program to automate the construction of the circle diagram, from which various operating characteristics of the motors will be deduced. Most results of various simulations carried out under the automated circle diagram are in good accordance with those predicted by theory. A second step is to determine the equivalent scheme parameters of the virtual machines modeled within Simulink/PSB. The simulated and experimental results were very close to each other. To close the loop between experiments, the automated MATLAB program, and the Simulink models, a virtual load test was carried out by coupling the asynchronous motor to a dc generator. The corresponding load point was validated on the circle diagram. An assessment is provided to reflect the positive impact of the proposed methods for enhancing an IM course with laboratory tests.
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Fig. 20. Flowchart for conceiving the MATLAB program.
APPENDIX The synoptic scheme of the proposed study is shown in Fig. 19. The flowchart for conceiving the MATLAB program is shown in Fig. 20. REFERENCES [1] S. Ayasun and C. O. Nwankpa, “Induction motor tests using MATLAB/ Simulink and their integration into undergraduate electric machinery courses,” IEEE Trans. Educ., vol. 48, no. 1, pp. 165–169, Feb. 2005. [2] K. A. Nigim and R. R. DeLyser, “Using MathCad in understanding the induction motor characteristics,” IEEE Trans. Educ., vol. 44, no. 2, pp. 165–169, May 2001. [3] M. W. Daniels and R. A. Shaffer, “Re-inventing the electrical machines curriculum,” IEEE Trans. Educ., vol. 41, no. 2, pp. 92–100, May 1998. [4] M. H. Nehrir, F. Fatehi, and V. Gerez, “Computer modeling for enhancing instruction of electric machinery,” IEEE Trans. Educ., vol. 38, no. 2, pp. 166–170, May 1995. [5] T.-F. Chan, “Analysis of electric machines using Symphony,” IEEE Trans. Educ., vol. 35, no. 1, pp. 76–82, Feb. 1992. [6] H. A. Smolleck, “Modeling and analysis of the induction machine: A computational/experimental approach,” IEEE Trans. Power Syst., vol. 5, no. 2, pp. 482–485, May 1990. [7] K. Zellagui and F. Saadi, “Etude expérimentale d’une génératrice asynchrone,” DEUA thesis, Dépt. Electrotechnique, Univ. Mentouri de Constantine, Constantine, Algeria, Jun. 2008. [8] T. Birem and H. Amiar, “Prédétermination des caractéristiques d’une machine asynchrone à partir d’essais expérimentaux sous puissances réduites sous Malab/Simulink,” Engineer thesis, Dept. Electrotechnique, Univ. Mentouri de Constantine, Constantine, Algeria, Jun. 2009. [9] T. Wildi and G. Sybille, Electrotechnique, 4th ed. Brussels, Belgium: De Boeck, 2005. [10] M. Kostenko and L. Piotrovski, Machines électriques, 3rd ed. Moscow, Russia: Mir, 1979, vol. 2. [11] M. Imecs and I. Incze, “A simple approach to induction machine parameter estimation,” in Proc. Workshop Elect. Mach. Parameters, Romania, May 26, 2001, pp. 73–80.
[12] J. Yviquel, “Contribution à l’étude de fonctionnement des moteurs d’induction à rotor bobiné et à cages multiples,” Annales de la faculté des Sciences de Toulouse, Univ. P. Sabatier vol. 15, no. 4, pp. 79–54, 1951. [13] A. Boglietti, A. Cavagnino, L. Ferraris, and M. Lazzari, “Skin effect experimental validations of induction motor squirrel cage parameters,” in Proc. ICEM, Vilamoura, Portugal, Sep. 6–9, 2008, Paper ID 931. [14] F. Ferreira, A. Almeida, and G. Baoming, “Three-phase induction motor simulation model based on a multifrequency per-phase equivalent circuit considering stator winding MMF spatial harmonics and thermal parameters,” in Proc. ICEM, Chania, Greece, Sep. 2–5, 2006, Paper no. 549. [15] A. Warzecha, “Computation of non-linear characteristics for windings for saturated induction slip ring motor,” Periodica Polytechnica Ser. El. Eng., vol. 45, no. 3–4, pp. 291–300, 2001. [16] M. Poloujadoff, “Machines asynchrones, Régime permanent,” Techniques de l’Ingénieur, Traité Génie Electrique, vol. D 3 480, pp. 1–17. [17] “Lab Electrical Power Engineering I,” Institut Fùr Electrische Maschinen, KWTH, Aachen, Germany, Aug. 23, 2004. [18] “The asynchronous machine model,” Arnhem, The Netherlands, Tech. Rep. 06-054 pmo, Phase to Phase BV, Apr. 5, 2006. [19] J. Bacher and F. Waldhart, “Online efficiency diagnostic of three-phase asynchronous machines from start-up data,” in Proc. ICREPQ, Valencia, Spain, Apr. 15–17, 2009. [20] E. Muljadi, P. W. Carlin, and R. M. Osgood, “Circle diagram approach for S.E.I.G.,” in Proc. North Amer. Symp., Washington, DC, Oct. 11–12, 1993, pp. 664–671.
Amar Bentounsi was born in Ain-Beida, Algeria, in 1953. He received the “doctorate-engineer” degree from the University of Jussieu, Paris VI, France, in 1980. From 1995 to 1999, he worked on his Ph.D. dissertation in collaboration with the Cegely Laboratory of Ecole Centrale, Lyon, France. He joined the University of Constantine, Constantine, Algeria, in 1984 as an Associate Professor. He cofounded the Laboratory of Electrotechnics at Constantine (LEC), Algeria, in 1999. His current research interests are computeraided design (CAD) and failure analysis of electrical machines and renewable energy conversion systems.
BENTOUNSI et al.: COMPUTER-AIDED TEACHING USING MATLAB/SIMULINK FOR ENHANCING IM COURSE
Hind Djeghloud was born in Constantine, Algeria, in 1976. She received the B.S., M.S., and Ph.D. degrees in electric machines from the Department of Electrotechnics, Constantine University, Constantine, Algeria, in 2000, 2002, and 2007, respectively. In 2003, she joined the Department of Electrotechnics, Constantine University, as an Assistant Professor. She is currently a Lecturer in the same department. Her interests are in power electronics, including electric power quality, active power filters, pulse width modulation (PWM) converters, and renewable energy systems.
Hocine Benalla was born in Constantine, Algeria, in 1957. He received the B.S. degree from the University of Sciences and Technology of Oran, Oran, Algeria, in 1980; the M.S. and Doctorate Engineer degrees in power electronics from the National Polytechnic Institute of Toulouse, Toulouse, France, in 1982 and 1984, respectively; and the Ph.D. degree in electrical engineering from the University of Jussieu, Paris VI, France, in 1995. Since 1996, he has been with the Department of Electrotechnics, Constantine University, Constantine, Algeria, as a Professor. His current research field includes active power filters, pulse width modulation (PWM) inverters, electric machines, and ac drives.
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Tahar Birem was born in Mila, Algeria, in 1986. He received the B.S. degree in electric machines from the Department of Electrotechnics, where he came first in his class, Constantine University, Constantine, Algeria, in 2009. His field of interest is mainly focused on electrical machines.
Hamza Amiar was born in Ain-Beida, Algeria, in 1986. He received the B.S. degree in electric machines from the Department of Electrotechnics, where he came second in his class, Constantine University, Constantine, Algeria, in 2009. His field of interest is mainly focused on electrical machines.
