LabVIEW based Electrical Machines Laboratory for Engineering Education

Transcription

1 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar abew based Electrical Machines aboratory for Engineering Education 1.. JBB KHN, 2. MOHMMED, 1 M. JUND, 1 M.. MSOOD ND 1. KH 1 achna College of Engineering & echnology (CE), Gujranwala, Pakistan 2 Universiti Kebangsaan Malaysia (UKM) [email protected] bstract: - he aboratory session in any engineering education particularly in Electrical Engineering is critical as these abs are designed for students in accordance with theoretical course work. Software based Electrical Machines cost less and have provision of wide ranging change in parameters as compared to hardware based ab, which results in better understanding of students in learning concepts of Electrical Machines course. Software based aboratory experiments have become current day need due to its impacts on flexible learning of students and understanding abilities. his motivation deals with Simulation of Electrical Machines aboratory experiments which are part of ab session at under-graduate Electrical Engineering level using aboratory irtual nstrument Engineering Workbench (abew) software. abew uses graphical language which allows a natural, vivid and user-friendly interaction. Key-Words: - Electrical Machines, Simulation, abew, Engineering Education 1 ntroduction his research work is the up-gradation of previous research published in CCESSE 2010 and WSES 2010 in which Electrical Machines- (EE243) and Machines- (EE350) experiments have been simulated respectively using abew software. hese courses are being taught at achna College of Engineering & echnology (CE), Gujranwala, Pk. in 4 th and 5 th term at undergraduate Electrical Engineering [1], [2]. Electrical Machines is one of the major subjects of Electrical Engineering. Electrical Machines- course covers the basics of ransformers and DC machines and Electrical Machines- contains Synchronous and nduction machines etc. n this research work the complete ab session of Electrical Machines course has been simulated using abew software. he fundamental equations of ransformer, DC machines and nduction machine using their equivalent circuits have been imparted into the abew for Simulation purpose [3], [4]. he concept for the use of abew software in Engineering education is recognized internationally but the complete ab Experiments of Electrical Machines course has been implemented in abew based upon the exact ratings and on-ground machines parameters as a pioneer and novel research at CE [5] [11]. Simulation of Synchronous machines have already been implemented in abew but DC machines, ransformer and nduction machines keeping in view the ab session requirement were not addressed potentially [12], [13]. he latest trends in education particularly in engineering education like eearing, new models of teaching etc. have also been introduced internationally [14] [16]. Other programming tools like MB, PSCD and Skyab etc. are also used for aboratory experiments simulation purpose but due to strong graphical user interface abew is preferred on all others [17], [18]. he list of experiments for Electrical Machines- course which has been simulated during this research work is as follows: oad Characteristics of a Separately Excited DC Motor oad Characteristics of a Shunt DC Motor oad Characteristics of a Series DC Motor oad Characteristics of a Separately Excited DC Generator oad Characteristics of a Shunt DC Generator oad Characteristics of a Series DC Generator Calculation of the Parameters of ransformer using Open Circuit & Short Circuit ests Calculation of oltage egulation for a Single Phase ransformer ist of experiments related to Electrical Machines- simulated in abew is follows: Equivalent circuit parameters of an nduction Motor oad est of a hree Phase nduction Motor oad est of a Single Phase nduction Motor orque Speed relationship of an nduction Motor nduction Motor as an nduction Generator Circuit model parameters of an nduction Motor Section 2 of this research is brief introduction to abew software. Section 3 deals with the implementation of Electrical Machines- ab experiments. Section 4 explains the Simulation of Electrical Machines- experiments. Section 5 is the Conclusions of this research work. Section 6 contains the eferences used in this research work. SSN: ssue 5, olume 7, May 2010

2 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar 2 ntroduction to abew software abew stands for aboratory irtual nstrument Engineering Workbench which is a graphical programming language, based upon icons/buttons instead of lines/programming codes for application purpose. his software has the ability to build user defined interface with set of objects and graphical tools. hese programs are labelled as irtual nstruments, or s, owing to their operational replica of physical instruments, like oscilloscopes, multi-meters etc. irtual nstrument is the combination of following three components: a. ront panel b. Block diagram c. con and connector pane Using above mentioned functions of abew, the complete course of Electric Machines at under-graduate level has been simulated [19]. ig. 1. Block Diagram of Separately Excited DC Motor he specifications of different components are shown in the ront Panel as shown in ig. 2, where different design, input parameters, voltage and speed parameters are given. 3 Simulation of Electrical Machines- aboratory Experiments 3.1 oad Characteristics of Separately Excited DC Motor separately excited DC motor can be defined as a motor in which a separate constant voltage power is supplied to field circuit. he fundamental mathematical relations for above mentioned motor are [3]: = (1) = (2) + (3) = ield circuit current = ield circuit voltage = ield circuit resistance = oad current = rmature current = erminal voltage E = nternally generated voltage = rmature resistance During modeling in abew, block diagram consisting of different components related to the designing of the separately excited DC motor from the function menu have been assembled according to the requirements based upon mathematical relations given in Equ. s 1, 2 and 3 respectively. Block Diagram of a separately excited DC motor is shown in ig 1. ig. 2. ront Panel of Separately Excited DC Motor During this experiment, the load characteristics like nternal Generated oltage (E ), Speed (w o ), nduced orque ( ind ), Output Power and Efficiency can be evaluated. hese self-explanatory results are shown in the given graphs of ig. s 3, 4 and 5 respectively. ig. 3 Graph for Output Power vs orque ig. 4 Graph for Output Power vs Speed SSN: ssue 5, olume 7, May 2010

3 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar ig. 5. Graph for Output Power vs Efficiency ig. 9. Output Power vs Efficiency 3.2 oad Characteristics of a Shunt DC Motor motor whose field circuit is supplied directly from armature terminals is known as a Shunt DC motor. he mathematical relations related to the equivalent circuit of a DC Shunt motor are given as [3]: = (4) = + (5) + (6) he design and input parameters for this experiment are given in ig oad Characteristics of a Series DC Motor Series DC motor is a motor whose field winding is connected in series with armature winding. ts mathematical relations are [3]: = = S (7) + ( + S ) (8) he design and input parameters for Series DC Motor are given in ig. 10. ig. 6. nput and Design parameters of Shunt DC Motor he different graphs obtained for the experimental values are shown in the ig. s 7, 8 and 9 respectively. ig. 10. nput & Design parameters of Shunt DC Motor he different experimental results are shown graphically in the ig. s 11, 12 and 13 respectively. ig. 7. Output Power vs orque ig. 11. Output Power vs orque ig. 8. Output Power vs Speed ig. 12. Output Power vs Speed SSN: ssue 5, olume 7, May 2010

4 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar ig. 13. Output Power vs Efficiency 3.4 oad Characteristics of a Separately Excited DC Generator n Separately Excited DC generator, a separate DC source is used to supply the field current. he characteristics of this generator are given as [3]: = (9) (10) = (11) Experimentally different load characteristics of a Separately Excited DC Generator have been studied by changing the input parameters which are shown in ig 14. ig. 16. oad current vs nternal Generated oltage 3.5 oad Characteristics of a Shunt DC Generator generator having its field connected to its own terminal to supply the field current is called a Shunt DC Generator. he equivalent circuit relations are [3]: = + (12) (13) = (14) oad characteristics of a Shunt DC Generator have been studied by changing the given input parameters which are shown in ig 17. ig. 14. nput and Design parameters of Separately Excited DC Generator he results are obtained by maintaining the same Speed of the Prime Mover and linearly increasing the oad Current which are shown graphically in the ig. s 15 and 16 respectively. ig. 17. nput and Design parameters Graphical results obtained during this experiment are shown in ig, s 18 and 19. ig. 15. oad Current vs erminal oltage ig. 18. oad current vs erminal oltage SSN: ssue 5, olume 7, May 2010

5 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar ig. 19. ield Current vs nternal Generated oltage 3.6 oad Characteristics of a Series DC Generator n a Series DC generator field winding is connected in series with armature winding. he fundamental mathematical relations for this generator are given as [3]: = = S (15) ( + S ) (16) he nput and design parameters are given in ig. 20. ig. 20. nput and Design parameters By changing the Speed of the Prime Mover, the nternal Generated voltage changed. he same Speed of the Prime Mover is maintained and the oad Current is increased resulting in increase in the rmature oltage Drop and Series oltage Drop and decreased in the erminal oltage as graphically shown in ig. s 21 and 22 respectively. ig. 22. ield Current vs nternal Generated oltage 3.7 Calculations for the Parameters of ransformer using Open Circuit est and Short Circuit est transformer is a device that transforms the electric power from one voltage level to another. he relationship between primary/ secondary voltages and currents are given as [20]: p ( t) N p = = a s ( t) N s (17) p ( t) N s 1 = = ( t) N a (18) s p (t) = Primary side voltage p s (t) = Secondary side voltage p (t) = Primary side current p (t) = Secondary side current N s = No. of Secondary turns N = No. of Secondary turns p Design of a Single Phase ransformer is taken experimentally by Open Circuit est Data ( oc, oc, P oc ) and Short Circuit est Data ( sc, sc, P sc ). ig. 23 nput parameters and esults of ransformer ig. 21. oad current vs erminal oltage he Unknown Parameters which are Core esistance ( c ), Magnetizing eactance (X m ), Equivalent esistance ( eq ) and Equivalent eactance (X eq ) have been calculated. SSN: ssue 5, olume 7, May 2010

6 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar 3.8 Calculation of oltage egulation for a Single Phase ransformer he nput Parameter is the esistive and nductive oad which is connected to the secondary of the Single Phase ransformer as shown in ig. s 24 and 25. ig. 24. Design parameters of Single Phase ransformer ig. 25. nput parameters of Single Phase ransformer Unknown parameters of transformer and Power actor of given load is calculated here. With the increase in the esistive and nductive oad, the power factor decreases. t is also observed experimentally that the voltage regulation becomes poor with the increase in the oad which is shown in the ig f e nsync = (19) P f e = System frequency P = No. of poles nduced voltage in rotor is given as: e ind = ( v. B). (20) v = velocity of rotor B = magnetic flux density vector = length of conductor in thee magnetic field nduced torque in induction motor is: τ ind = kb BS (21) B = otor magnetic field B S = Stator magnetic field he slip of the rotor is defined as: nsync nm s = (22) nsync n slip = slip speed of machine n sync = speed of magnetic fields n m = mechanical shaft speed of motor he rotor frequency can be stated as: f r = sf e (23) Or, P f r = ( nsync nm ) (24) 120 n block diagram different components are arranged related to the designing of an induction motor from the function menu and assembled according to the requirements during modeling in abew. hese block units helped to make a general layout of an induction motor as shown in ig. 27. ig. 26. oad vs % egulation 4 Simulation of Electrical Machines- aboratory Experiments 4.1 Equivalent Circuit Parameters of an nduction Motor n induction motor is an C motor in which power is supplied to rotor with electromagnetic induction. he fundamental relations associated with nduction motor are given below [21]. he speed of magnetic field s rotation can be calculated as: ig. 27. Block diagram of an induction motor ront Panel diagram for equivalent circuit model parameters of an nduction Motor is shown in ig. 28, SSN: ssue 5, olume 7, May 2010

7 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar where different design parameters and the input parameters are shown. ig. 30. ariation in shaft speed of 3/P induction motor Graphs in ig. s 31, 32, 33, 34 and 35 show the behavior of three phase induction motor during this experiment. ig. 28. Design and input parameters t is observed experimentally that by increasing the otor s mechanical shaft speed, the values of Slip, Stator Current and otor Current increases and the value of Equivalent mpedance decreases. hese results are shown in the able 1. able 1 esults for Equivalent Circuit parameters Slip j j Z tot j 4.2 oad est of a hree Phase nduction Motor or load test of a hree Phase nduction motor, the design parameters are shown in ig. 29. ig. 31. Output Power vs. Efficiency ig. 32. Power actor vs. Efficiency ig. 33. orque vs. Efficiency ig. 29. Design parameters of 3/P induction motor he variable parameter is only the rotor s mechanical shaft speed (n m ). he value of the rotor s mechanical shaft speed must be less than the synchronous speed. By changing this value results will also be changed. ig. 34. orque vs. Slip SSN: ssue 5, olume 7, May 2010

8 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar ig. 35. Speed vs. Efficiency ig. 39. Power actor vs. Efficiency 4.3 oad est of a Single Phase nduction Motor he design and input parameters for a single phase induction motor are given in the ig 36. ig. 40 shows the relationship between Speed and Efficiency, and it is observed that with the increase in the rotor s mechanical shaft speed, Efficiency goes on decreasing. ig. 40. Speed vs. Efficiency ig. 36. Design and input parameters of single phase induction motor ig. 41 shows that with the increase in orque, the value of Slip also increases for the single phase induction motor. ig. s 37, 38 and 39 respectively show the linear relation between (Output Power, Power actor and orque) vs. Efficiency. ig. 41. orque vs. Slip ig. 37. Output Power vs. Efficiency 4.4 orque Speed elationship of an nduction Motor he design parameters for torque speed relationship of an induction motor experiment are given in the ig. 42. ig. 38. orque vs. Efficiency ig. 42. Design parameters for torque speed relationship of an induction motor SSN: ssue 5, olume 7, May 2010

9 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar t is observed that with the increase in the rotor s mechanical shaft speed, the value of nduced orque decreases. ig. 43. nput parameters and esults for torque speed relationship of an induction motor he graph shown in ig. 44 describes the torque-speed characteristics of an induction motor. ig. 46. nput parameters & esults Graph in ig. 47 shows the orque vs Speed relation. he portion of the graph showing the positive value of nduced orque above the zero-axis is the motor region. he portion of the graph showing the negative value of nduced orque below the zero-axis is the generator region. ig. 44. orque vs. Speed of an induction motor 4.5 nduction Motor as an nduction Generator he design parameters for this experiment are given in the ig. 45. ig. 47. orque vs. Speed 4.6 Circuit Model Parameters of an nduction Motor he input parameters for this experiment are requency, DC est data values ( DC, DC ), No oad est Data alues (,, B, C, P N, and ) and ocked otor est data values (,, B, C, P N, and ) which are given in the ig. 48. ig. 45. Design parameters of an induction motor when run as induction generator he nput parameter the results are shown in the ig. 46. ig. 48. nput parameters for circuit parameters of an induction motor SSN: ssue 5, olume 7, May 2010

10 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar Experimental results of these three ests are verified one by one. t is worth mentioning here that: DC est is used to calculate the value of Stator esistance ( 1 ) No oad est is used to calculate the otational osses (P rot ) and No oad mpedance (Z nl ) ocked rotor est is used to calculate ocked otor esistance ( ) and ocked otor eactance (X ). hese circuit parameter results are shown in the ig. 49. ig. 49. Circuit parameters results of an nduction Motor 5 Conclusions he idea of Electrical Machines ab experiments Simulation using abew software is being successfully put into operation at CE Electrical Engineering Department (EE Deptt.) which results in outstanding feedback of students ab work evaluation. he same idea can also be extended for other courses ab sessions in parallel with hardware based abs. he Simulation performed during this research work can also utilized as on-line experiments performance not only at Campus level but also at National and nternational levels using latest information technology tools. eferences: [1].. Jabbar, zah Mohamed, M.. Hannan, Muhammad Junaid, M. Mansoor,.atif and H. Noor, Simulation of Electrical Machines aboratory Using abew, nternational Conference on Computer, Electrical, and Systems Science, and Engineering (CCESSE 2010), World cademy of Science Engineering and echnology (WSE), SSN: & SSN: , Cape own, South frica, January 29-31, [2] ana. Jabbar, Muhammad Junaid, M. li Masood, M. Mansoor and dil ftkhar, abew based nduction Machines aboratory for Engineering Education, he 7th WSES nternational Conference on Engineering Education (Education '10), SBN: , Corfu sland, Greece, July, 22-24, [3] Stephen J. Chapman, Electric Machinery undamentals, 4 th Edition, McGraw-Hill, 2005, SBN: , Ch. 9 DC Motors and Generators, pp [4] C. Elliott,. ijayakumar, W. Zink and. Hansen, National nstruments abew: Programming Environment for aboratory utomation and Measurement, Journal of the ssociation for aboratory utomation, olume 12, ssue 1, ebruary [5] Basher, H.. sa, S.., On-Campus and Online irtual aboratory Experiments with abew, South east Conference, Proceedings of the EEE, SBN: , Digital Object dentifier /second , South Carolina State Univ., Columbia, SC, March 31, 2005-pril 2, [6] ento, J.., pplication of abew in higher education laboratories, rontiers in Education Conference, Digital Object dentifier: /E , ustin, X, US, July 08, [7] Wang, J.Y.-Z., abew in engineering laboratory courses, rontiers in Education (E 2003), SSN: , SBN: , Digital-Object-dentifier: / E , Potomac State Coll., West irginia University., US, 5-8 Nov [8] Higa, M.. awy, D.M. ord, S.M., n introduction to abew exercise for an electronics class, rontiers in Education, E nd nnual, SSN: , SBN: , Digital Object dentifier: /E , On page(s): 1D-13-1D- 16 vol.1, University of San Diego, 6-9 Nov [9] Sherry,.. ord, S.M., abew as an effective enhancement to an optoelectronics laboratory experiment, rontiers in Education Conference, th nnual Conference. 'eaching and earning in an Era of Change'. Proceedings, SBN: Digital Object dentifier: /e , On page(s): vol.2, Pittsburgh, P, 5-8 Nov [10] Nunnally, C.E. eaching EE circuits lab with abview, rontiers in Education Conference, E '96. 26th nnual, SBN: , NSPEC ccession Number: , olume: 2, On page(s): vol.2, 6-9 Nov 1996, Salt ake City, U, US. [11] du Preez, S.J. Sinha, S. Hutton, M. Nat. nstrum., Midrand abew courseware customized for precollege learners, CON 2007, On page(s): 1 6, SBN: , Digital Object dentifier: /CON , Sept. 2007, ocation: Windhoek. [12] M. Usama Sardar, Synchronous Generator Simulation Using abew, Proceedings of World cademy of Science, Engineering & echnology (WSE), SSN , olume 29, May [13] Biro K.. Szabo. ancu,. Hedesiu, H.C. Barz,, On the Synchronous Machine Parameter dentification, Workshop on Electrical Machines, echnical University of Cluj-Napoca, 26 May [14] Daniela Cristiana lexandrescu, on oncea, alentina Ofelia obescu, omanian E-earning Experience in Ecological griculture, he 7th WSES nternational Conference on Engineering Education (Education '10), SBN: , Corfu sland, Greece, July, 22-24, SSN: ssue 5, olume 7, May 2010

11 WSES NSCONS on DNCES in ENGNEENG EDUCON.. Jabbar Khan,. Mohammed, M. Junaid, M.. Masood,. ftkhar [15]. ejeda,. Santamaria, Models in eaching: Powerfull Skill, he 7th WSES nternational Conference on Engineering Education (Education '10), SBN: , Corfu sland, Greece, July, 22-24, [16] Petra Poulova, Barbora esarova, Martina Manenova, Efficiency Comparison of eearning Supported nstruction to raditional University Courses in the Subject of Database Systems 2, he 7th WSES nternational Conference on Engineering Education (Education '10), SBN: , Corfu sland, Greece, July, 22-24, [17] S. inke, J. orgeson, and J. u, n interactive computer-graphics program to aid instruction in electric machinery, EEE Comput. pplicat.power, July [18]. Krishnan,. Bharadwaj, and P. Materu, Computer aided design of Electrical machine for variable speed applications, EEE ransaction, nd.electron., vol. 35, no. 4, Nov [19] National nstrumentation (N) abew, [20] Stephen J. Chapman, Electric Machinery undamentals, 4 th Edition, 2005, McGraw-Hill, SBN: , Ch. 2 ransformers, pp [21] Stephen J. Chapman, Electric Machinery undamentals, 4 th Edition, 2005, McGraw-Hill, SBN: , Ch. 7 nduction Motor, pp SSN: ssue 5, olume 7, May 2010