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532 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 20, NO. 2, MAY 2005

Development of Power System Protection LaboratoryThrough Senior Design Projects

Bhuvanesh A. Oza and Sukumar M. Brahma, Member, IEEE

Abstract—This paper describes a novel power system labora-tory at Birla Vishvakarma Mahavidyalaya (B.V.M.) EngineeringCollege, Gujarat, India, where every experiment was designed,wired and commissioned through senior design projects. Theexperiments on power system protection are especially unique interms of their design and implementation and will be highlightedin this paper. They provide a real substation-like operating en-vironment. Through these projects, the students, in addition togetting familiar with the fundamentals of protection, learned howdifferent protection schemes are wired and how they operate ina real power system. For the institute, a quality laboratory wasestablished at a low cost, which is a crucial issue for most collegesin many parts of the world.

Index Terms—Circuit breaker, fault, power distribution system,power engineering education, power system protection, protectivedevice coordination, relay.

I. INTRODUCTION

OVER the past two decades, different laboratories focusingon teaching and researching the area of power system pro-

tection have been reported [1]–[8]. Sidhu and Sachdev [1], [2]describe a laboratory at the University of Saskatchewan that fo-cuses on designing relay strategies, modeling them and testingthem using high speed digital signal processing (DSP) boardsand an array of design softwares. Redfern et al. [3] describetesting relays using actual voltage and current data convertedfrom the data files generated by power system simulation soft-ware. Lee et al. [4] report a relay performance testing facilityusing simulated transmission line modules. The paper describesboth the hardware and the software strategy and documents theperformance results of an instantaneous overcurrent relay and areverse power relay. Carullo and Nwankpa [5] describe a labo-ratory that focuses on the data acquisition, energy managementand supervisory control aspects of a power system that formthe basis of a modern protection system. Kabir [6] documentsthe performance of a laboratory experiment on a scaled downpower system protected by a single computer implementing anover-current protection strategy. Chen et al. [7] report the lab-oratory implementation of an intelligent embedded micropro-cessor based overcurrent protection scheme. McLaren et al. [8]report a relay testing facility based on Real Time Digital Simu-lator (RTDS).

Manuscript received February 18, 2004; revised May 28, 2004. This workwas supported by a grant from the All India Council for Technical Education(AICTE). Paper no. TPWRS-00087-2004.

B. A. Oza is with the Electrical Engineering Department, B.V.M. Engi-neering College, Vallabh Vidyanagar, Gujarat, India (e-mail: [email protected]).

S. M. Brahma is with the Electrical Engineering Department, Widener Uni-versity, Chester, PA 19013, USA (e-mail: [email protected]).

Digital Object Identifier 10.1109/TPWRS.2005.846200

The laboratory described in this paper is a result of the grantof 1 500 000 rupees (approximately US$33 300) obtained formthe All India Council for Technical Education (AICTE). Thelaboratory is designed to be used for illustrating the fundamen-tals of power system (concentrating more on protection) and asa professional relay testing and high voltage testing facility. Thedistinguishing aspects of this laboratory are several. All the ex-periments in this laboratory are conceived, designed and imple-mented through senior design projects. This helped in cuttingdown the cost tremendously as the grant was used only in pur-chasing high quality professional grade equipment for the lab-oratory, instead of buying expensive integrated systems fromvendors. This also meant that a complete freedom to designthe laboratory was left to the students and the faculty involved.This indeed led to a very innovative design. Every panel was sodesigned that it looked and functioned very similar to a panelin any actual substation. This gave the students, who subse-quently performed the experiments as a part of their course-work, a real-life feel of a power system. In addition, since thisapproach allowed the purchase of professional grade equipmentfrom the grant money, some equipment could be used for pro-fessional testing, generating revenue for the college.

The following sections describe the features of the laboratoryand the development process of the senior projects in detail.

II. PURCHASE AND USE OF EQUIPMENT

About 107 relays were purchased from the grant. Theseincluded fifty one overcurrent relays, three thermal relays,forty one auxiliary relays, seven differential relays, two motorprotection relays, one negative phase sequence relay and tworeverse power relays. The overcurrent relays were of all typeslike directional, nondirectional, phase, ground, definite time,instantaneous, and inverse definite minimum time (IDMT) withvarying degree of inverse curves. All the relays were eitherelectromechanical or static. The relays were bought during thetime period from the late eighties to the early nineties whenthe cost of electromechanical and static relays was cheaperthan digital relays. The other consideration for buying theserelays was that about 98% or more relays in use all over thecountry were of these types then and were likely to remainin service for many years to come. Thus it was felt that thegraduating students must have an exposure to these types ofrelays. However, from a subsequent grant, digital relays wereprocured during the late nineties and are also used in thislaboratory now. The other major equipment bought from thegrant were an English Electric make overcurrent relay test set,a 180–250-V, 100-A dc rectifier to provide auxiliary voltage tothe relays and contactors, thirty three-phase power contactorsand miscellaneous items like push buttons, semaphore and

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OZA AND BRAHMA: DEVELOPMENT OF POWER SYSTEM PROTECTION LABORATORY 533

neon indicators, buzzers, control switches, capacitors, singlephase transformers, miniature circuit breakers (MCBs), etc. Apart of this grant was also utilized in procuring equipment for ahigh-voltage laboratory including a 100-kV high-voltage trans-former with related accessories, a 100-kV, 100-pF measuringcapacitor and an electrolytic tank.

Once the equipment were procured, the students startedworking on designing and implementing different experimentsin groups of two or three for their senior projects guided byfaculty. Every year, about 30 to 35 students register for thesenior project (EE 421) course. Out of these, about 12 to 15students worked for the laboratory development. The laboratorywas planned to serve four undergraduate courses. A list of theexperiments working now for each of these courses as a resultof this work is as follows.

A. Power System—I

In this junior level course, the following experiments werecreated:

1) to observe the effect of a floating star point on a three-phase distribution system;

2) to observe the voltage distribution along a string of sus-pension insulators;

3) to observe the performance of a transmission line usingthe short and the medium line models;

4) to observe the characteristics of an MCB.

B. Power System—II

In this junior level course, the following experiments werecreated:

1) to observe the characteristics of a thermal relay;2) to observe the characteristics of time delayed overcurrent

relays. This includes definite time and IDMT relays withvarying degree of inverse curves;

3) to observe the characteristics of a directional overcurrentrelay;

4) to observe the characteristics of a differential relay; bothbiased and unbiased differential relays were used in thisexperiment.

C. Power System Protection

In this senior level course, the following experiments werecreated:

1) to understand the fundamentals of a radial protectionscheme;

2) to understand the fundamentals of the protection of twoparallel feeders;

3) to study the feeder protection scheme using two overcur-rent and one earth fault relays;

4) to study generator differential protection;5) to study transformer differential protection;6) to study the protection of an induction motor;7) to study the principles of reverse power protection.In addition to these experiments, the students perform

some experiments involving testing insulation strengths ofdifferent dielectric materials and field plotting as part of the“High-Voltage Engineering” course at the junior level.

From the equipment described in this section, the relay testingset and the high-voltage transformer are used for professionaltesting purpose, thus generating revenue for the college.

Since it is not possible to describe how each of the exper-iments is designed and implemented, the next section willdescribe an experiment in power system protection that willcapture the innovative but simple design features and hardwaredetails of all the experiments.

III. DESCRIPTION OF HARDWARE AND EXPERIMENTS

In this section, the experiment designed to understand theconcept of radial feeder protection will be described. Fig. 1shows the main circuit for the experiment. Three-line sectionsare simulated by 9-ohm resistors, each being controlled by thepower contact of a contactor (C1-1, C2-1 and C3-1). The relayfor each section is an IDMT relay fed through a 10/5-A currenttransformer (CT). Section III is connected to the load throughan MCB, which is the typical load controlling device at the con-sumer end. This can be replaced by a fuse if so desired. The loadconsidered here is the equivalent load at the primary of the distri-bution transformer at the consumer-end. The circuit is suppliedwith 230-V, 50-Hz, single-phase ac supply. Except for experi-ment number 3 in Section II-C, each experiment was built with asingle line circuit to economize on the number of relays requiredfor each experiment. This, by no means affects the insight of-fered by the experiments, as the following description will show.It is worthwhile to note here that all the overcurrent relays arerated at 1 amp in order to be able to create faults without exces-sively loading the utility source. This becomes a serious issueespecially when two experiments are performed simultaneouslyby two groups of students. The switches S1, S2 and S3, whenswitched on, simulate a fault in Sections I, II and III, respec-tively. The location of the fault can be changed by changing thevariable terminal of the resistor modeling the line section. Thefault is made through a fault resistance of 18 ohms.

The students first calculate the relay settings required to coor-dinate these three relays using the system data. They are giventhe characteristics of the MCB, so relay R3 can be coordinatedwith the MCB for faults beyond the MCB. Once this is done,the students set the relay tap value (TV) and time setting multi-plier (TSM) according to their calculations. The circuit is thenenergized. Faults are created at both ends of each section andthe time of operation of the corresponding relays is measuredwith a timer. When the relay operates, a bulb glows and a buzzeroperates. The student has to push the “accept” button on thepanel to acknowledge the operation of the relay to set the buzzeroff. The semaphore indicator shows the “open” status of the cir-cuit breaker (contactor) when the contactor opens to isolate thefaulted section. This is exactly the way it happens in a real sub-station. Fig. 2 shows the control circuit for the experiment.

As shown in Fig. 2, the control circuit is wired to a 110-V dcsupply simulating the battery bank in a substation. A rectifier isused in the laboratory that supplies all the experiment-bencheswith the required dc supply. In Fig. 2, R1-1, R2-1 and R3-1are the main relay contacts. A1, A2 and A3 are the auxiliaryrelay coils, which remain de-energized unless the correspondingcontact of the main relay closes. C1, C2 and C3 are the contactorcoils.


Fig. 1. Main circuit for the experiment on radial feeder protection.

Fig. 2. Control circuit for the experiment on radial feeder protection.

To energize the circuit, the circuit breakers (contactors here)have to be turned on. This is done by pushing the button PB-1.When PB-1 corresponding to the line Section I is pressed, thecontactor coil C1 will be energized since the normally closed(NC) contact of A1, A1-1, is closed. This would make the con-tactor “ON” closing the power contact C1-1 in the main circuitshown in Fig. 1. This will also close the contact C1-2 to keep thecontactor coil energized after the push button PB-1 is released.Similarly by pressing push buttons PB-1 associated with lineSections II and III, the contactors C2 and C3, respectively, canbe made “ON.” Thus, the whole main circuit is energized (theMCB is switched on manually). To open any “circuit breaker”manually, the corresponding PB-2 push button has to be pressed.As shown in Fig. 2, the bulbs L1, L2 and L3 are “ON” when thecorresponding contactors are “ON” and vice versa. These bulbsare “circuit breaker status” bulbs on the panel.

Let us trace the operation pattern under a fault, when say,relay R1 operates. This results in closing the contact R1-1,which energizes the auxiliary relay coil A1. Since A1 ener-gizes, the normally open (NO) contact A1-2 closes and theauxiliary relay gets an alternate path to remain energized evenafter the main relay drops off. The auxiliary relay will openthe contact A1-1 which results in the contactor coil C1 gettingde-energized opening the main contact C1-1 of the “circuitbreaker.” The operation of the other two relays will similarlyresult into the opening of the corresponding “circuit breaker.”The only difference in the control circuits of relays R2 and

R3 from that of R1 is the connection of switches T2 and T3.These are used to check the back-up operation. If the switchT2 is opened, the operation of relay R2 will not be able toopen the corresponding “circuit breaker” because A2 cannotbe energized. This simulates the “stuck” circuit breaker or aproblem with the control wiring that requires back up. Thestudents measure the operating time of the main relays as wellas the back up relays for different fault locations and compareit with their calculations.

Fig. 3 shows the connection of the indicating devices, viz.,alarm, bulb and semaphores. As can be seen from the figure,as long as the contactor coil is energized, the correspondingsemaphore indicator coil is energized. This means that the sema-phores will show the line section as “energized.” When the “cir-cuit breaker” opens, the semaphore will indicate the de-ener-gized status of the line section. Moreover, the operation of anyauxiliary relay (as a result of the main relay operating under afault) will close the corresponding contact (A1-3, A2-3 or A3-3)activating the buzzer and the bulb. The user then has to press the“accept” push button “PB3” in Fig. 2. This will de-energize theauxiliary relay and deactivate the buzzer and the bulb in Fig. 3.

Fig. 4 shows how the operating time of a relay is measured.A digital timer is used for this purpose. The fault-activatingswitches S1, S2 and S3 are connected in parallel with the “start”contact of the timer. The timer starts when the “start” contactcloses, which means, in this case, when the fault is created. Thetimer stops when any of the auxiliary relay is energized by the


Fig. 3. Indication and alarm circuit for the experiment on radial feederprotection.

Fig. 4. Timer connections.

main relay, closing the corresponding contact A1-4, A2-4 orA3-4. Thus, the timer measures the time between the inceptionof a fault and the operation of a relay.

Through this experiment, students learn how a radial feederis protected. They learn to set the IDMT relays for such protec-tion. They can verify their calculated setting by actual experi-mentation. It is also possible to observe the effect of the sourceimpedance to line impedance ratio through this exper-iment. Students verify that in Section III, where the ratiois high, a normal-inverse IDMT relay does not provide signifi-cant time discrimination for faults at two ends of the feeder (therelay behaves almost like a definite time relay); whereas a veryinverse type IDMT relay performs much better. The energizingof the circuit and the operation under fault are so designed thatduring the performance of this whole experiment, the studentsget a real-life like feel.

Fig. 5 shows the picture of the panel erected for the exper-iment just described. It looks similar to a substation panel. Ascan be seen from the picture, the panel has a one-line diagram ofthe system with semaphore indicators. The pushbuttons to makethe “circuit breaker” on and off (PB1 and PB2) as well as the“accept” push buttons PB3 for each section can be seen. Therelays and the MCB are mounted on the panel. The fault-cre-ating switches S1, S2, S3 can also be seen. The switches T1 andT2 are mounted on the backside to avoid confusion. The “cir-cuit breaker status” bulbs and the alarm system of Fig. 3 are alsomounted on the panel. The contactors, auxiliary relays, rheostats

Fig. 5. Front panel view of the experiment.

and CTs are mounted on the bench at the back of the panel. Con-trol wiring is done exactly as done in substations, using num-bered ferrules to identify the two ends of a wire. The wholeexperiment involving design, fitting the equipment, wiring andcommissioning constituted one senior project. Other projects in-volved creating other experiments listed in Section II in a similarway. Thus, the students were exposed to all aspects of a partic-ular protection scheme and were challenged with translating allthe important features of the scheme to a user-friendly experi-ment that can be used by future students.

IV. STAGES OF THE PROJECT DEVELOPMENT AND THE

MEASURING TOOLS

Now that the nature of the experiments and primary detailsof the laboratory (the final product) is clear to the reader, thestages in which the completion of the projects was achieved willbe described in this section. Measuring tools used for evaluationwill also be mentioned.

A. Stage 1: Groundwork

The faculty members first determined the experiments to beperformed in this laboratory to support the syllabus for the ex-isting power curriculum. The part of the curriculum covered bythis laboratory deals with constructional, operational and mod-eling details of power generation, transmission and distributionsystems, power system protection and high voltage engineering.The experiments are already listed in Section II. This stage didnot involve any student input and was obviously accomplishedbefore the grant was procured.

B. Stage 2: Evolution of a Common Design Strategy

Once the project was funded, the faculty members involvedwith the project met several times over one semester to workout the implementation plan. The most challenging part of theproject was to design the experiments in such a way that theycan be implemented through senior design projects and yet notlose the thoroughness in covering the related concepts. Thus,both the hardware implementation and the educational deliverywere of essence.

The experiments described in Section II-A were alreadybeing performed at the time the proposal was written, but were


not permanently mounted. So it was decided to make them apart of the laboratory in the form of dedicated desktop panels.The thrust of the laboratory was on developing new experimentsin Power System Protection as listed in Section II-B and II-C.Since the basic nature of these experiments and the equipmentsrequired for them were similar, it was possible to employ acommon hardware strategy for all the experiments. It was feltthat this would standardize some design aspects and hencewould make it easier to implement the experiments throughsenior design projects.

Several ideas were considered to be adopted as a commonhardware strategy. Finally, it was decided to have all the exper-iments reflect the appearance and operation in a real substation.This was an important step because this was the feature that wasmost appreciated by all evaluators as unique. Circuit drawingsof an actual substation were studied, which led to the formationof a general idea of the main, control and indication circuitrysimilar to those shown in Figs. 1, 2 and 3 and the general ap-pearance shown in Fig. 5. It is easy to see that these circuitsresemble closely to the wiring diagram in any substation, andthe panel view resembles the panel of a substation. It was alsodecided to use rheostats to represent transmission and distribu-tion lines, because they enable to change the fault location easilyand are very cost effective. It was also decided to model the loadwith a rheostat to make it variable in order to observe the effectof the load current on relay settings. The design of the measure-ment circuitry was left for the students. Again, this stage did notinvolve any input from students.

C. Stage 3: Design

Now a group of three students was chosen to develop the firstexperiment. This experiment happened to the one described inSection III. The design tasks accomplished by the students canbe subdivided as below:

1. To be completely familiar with the underlying theory forthe experiment they were assigned.

The participating students had taken two basic coursesin Power Systems (Power System I and Power SystemII) at this point of time. This gave them knowledge ofdifferent types of relays, in addition to the constructional,operational and modeling details of power generation,transmission and distribution systems. In addition, theyregistered for a course on Power System Protectionconcurrently with the project. Therefore, this task wasaccomplished in one week.

2. To develop the experiment setup, procedure, learning out-comes, experiment-specific main, control and indicationcircuits as well as panel design.

The formation of procedure and learning outcomestook two weeks and needed close interaction with faculty.Since the general idea of the circuitry was already formedby faculty members as described in Section IV-B, thestudents came up with the specific circuits in Figs. 1, 2, 3and the panel design in Fig. 5 in two weeks.

3. To determine the ratings of the equipment to be used.The important factor considered here was to limit

the load on the electrical outlets (230 volts, 50 hertz,

single-phase) during normal and faulted operation. Thisdetermined the maximum load and fault current valuesallowed. Using these values, continuous and short timeratings of equipment like rheostats, contactors, currenttransformers, and relays were determined. Ratings of theindication devices, push buttons and the auxiliary relayswere determined from the dc rectifier output voltage (110volts). This was accomplished in one week. Now, circuitsshown in Figs. 1, 2 and 3 were finalized to the last detail.

D. Stage 4: Installation, Commissioning, Documentation,and Presentation

Once the ratings were approved by the faculty, the equipmentswere ordered. There were no budgetary constraints imposed onthe students. Since all the other experiments were to be designedwith this common strategy, and hence would have similar rat-ings, the faculty could order the equipment in bulk. This intro-duced some delay for the first senior project group, but for allother experiments in later years, the time to order equipmentwas saved. This was another advantage of the common designstrategy. The equipment list is given in Section II. Most of theitems were available with the local vendors. All the requireditems except relays could be procured in less than four weeks.The students utilized this time in working on the measurementcircuit design (see Fig. 4) and in preparing the wooden panelshown in Fig. 5. Since the students had used timers in otherexperiments, designing the measurement circuit was easily ac-complished. The panel, with the necessary slots (for relays) cut,and holes (for push buttons, bulbs, buzzer, semaphores, switchesand terminals) drilled, was mounted on a desk top with rightangle clamps, leaving about one foot wide desk-space behindthe panel.

As the equipments arrived, the work on installation of com-ponents and wiring the circuit started. The circuit was connectedadhering to the practices adopted in wiring sub station panels.Ferrules were used to identify wires and the wires were bunchedup behind the panel. CTs, contactors and auxiliary relays weremounted on the desktop surface behind the panel. Rheostatswere mounted on the rear flank of the desk itself. The processtook about three weeks.

Finally, the students performed the experiment, recorded allreadings, prepared a written report and presented formally to apanel consisting of faculty and local industry representatives.They also had to present their progress to the faculty twiceduring the semester in the form of a slide presentation.

During the course of the project, a very close interactionbetween the students and the faculty was maintained. Weeklymeetings provided the required brainstorming and monitoring.During the physical implementation, the faculty supervised theproject almost on a daily basis. The initial planning and de-tailing were done with so much care and collective inputs, andfollowed up by such close collaboration, that every experimentoperated as intended.

E. Other Experiments

The experiments described in Section II-A were relativelyeasy to implement. A group of two students worked over asix-month period to implement each of these experiments. The


experiments listed in Section II-B required a relay-testing panel.Two desktop panels were created to accommodate all the re-lays. Each panel was designed and commissioned by a groupthree students. In these projects, the students designed and im-plemented a comprehensive relay testing circuit that measuredthe supplied current and/or the applied voltage as well as thetime of operation of a relay, automatically disconnecting thesupply as soon as the relay operated. The features of the cir-cuit were similar to the circuits shown in Fig. 2 and Fig. 4. Thiscircuit produced results comparable with the results from theprofessional relay testing set mentioned in Section II.

Each experiment described in Section II-C was considered asa senior project and was undertaken by a group of three stu-dents. The high voltage part of the laboratory was profession-ally installed as a part of the purchase agreement, since thiswas beyond the scope of the students. All projects lasted forone semester. It is worthwhile to mention here that the semesterinvolved a three-week winter break, which was utilized by thestudents for concentrated effort. The listed projects were com-pleted over a period of five years.

F. Measuring Tools and Dissemination

The quality of the project itself (the hardware development)was evaluated by representatives from local industry as well asfaculty. The effectiveness of the educational delivery providedby the resulting experiments has been evaluated over the yearsby alumni who performed the experiments as part of theircoursework. Both evaluations have been extremely positive.Several alumni who joined power utilities after graduation feltvery comfortable working in a substation due to being exposedto a similar environment in the laboratory. The laboratory isbeing used as a model by some of the new colleges coming upin the state of Gujarat. This laboratory has also been lavishlypraised as one of its kind by a visiting committee from theAll India Council of Technical Education as well as officiallyrecognized by the Director of Technical Education for the stateof Gujarat. For further dissemination, the authors are planningto design a web page associated with the college web site(http://bvm.ecvm.net/) or with one of the authors’ home pages(http://quantum.soe.widener.edu:344/PS_Lab_BVM.html)where the laboratory manuals for all experiments will be madeavailable.

V. CONCLUSION

The paper describes a power system laboratory unique insome ways. It is prepared fully through senior projects. Thishas enabled the college to spend the entire grant in procuringquality equipment. From a really small sum of approximatelyUS$ 33 000, a laboratory has been created that encompasses allmajor fundamentals of power system through insightful exper-iments. This is very crucial for colleges in developing coun-tries. The laboratory is being used by approximately 180 stu-dents every year as a part of their coursework. In addition, thestudents from other nearby colleges regularly come to performexperiments in this laboratory. Another novel feature of the lab-oratory is that it provides a real substation like operating envi-ronment, especially for the protection related experiments. The

high voltage transformer and the relay testing set procured withthis grant, in addition to being used for experiments, are usedfor professional testing too, thus generating revenue for the col-lege. The process of fully integrating digital relays into the ex-periments is ongoing and constitutes the second phase of thelaboratory. This phase aims at creating experiments using theserelays that can illustrate, along with the protection fundamen-tals, the full capability of these relays to the students.

REFERENCES

[1] T. S. Sidhu and M. S. Sachdev, “Laboratory setup for teaching and re-search in computer-based power system protection,” in Proc. Int. Conf.Energy Manage. Power Del., vol. 2, 1995, pp. 474–479.

[2] M. S. Sachdev and T. S. Sidhu, “Laboratory for research and teachingof microprocessor-based power system protection,” IEEE Trans. PowerSyst., vol. 11, no. 2, pp. 613–619, May 1996.

[3] M. A. Redfern, R. K. Aggarwal, and G. C. Massey, “Interactive powersystem simulation for the laboratory evaluation of power system protec-tion relays,” in Proc. Int. Conf. Develop. Power Syst. Protect., vol. 302,1989, pp. 215–219.

[4] L. Wei-Jen, G. Jyh-Cherng, L. Ren-Jun, and D. Ponpranod, “A physicallaboratory for protective relay education,” IEEE Trans. Educ., vol. 45,no. 2, pp. 182–186, May 2002.

[5] S. P. Carullo and C. O. Nwankpa, “Interconnected power system labo-ratory: a computer automated instructional facility for power system ex-periments,” IEEE Trans. Power Syst., vol. 17, no. 2, pp. 215–222, May2002.

[6] S. M. Lutful Kabir, “Computer operated coordinated over-current pro-tection scheme,” in Proc. Univ. Power Eng. Conf., 2000 , pp. 79–83.

[7] Z. Chen, A. Kalam, and A. Zayegh, “Advanced microprocessor basedpower protection system using artificial neural network techniques,” inProc. Int. Conf. Energy Manage. Power Del., vol. 1, 1995, pp. 439–444.

[8] P. G. McLaren, R. Kuffel, R. Wierckx, R. J. Giesbrecht, and L. Arendt,“A real time digital simulator for testing relays,” IEEE Trans. PowerDel., vol. 7, no. 1, pp. 207–213, Jan. 1992.

Bhuvanesh A. Oza was born in Rajkot, India, in1950. He received the B.E. and M.E. degrees, both inelectrical engineering, from Sardar Patel University,Gujarat, India, in 1972 and 1982, respectively.

His industrial experience from 1974 to 1986includes working with Rakot Phones Subdivision,Baroda Meters, and Gujarat Electricity Board(GEB). At Baroda Meters, he was in charge ofenergy meter production. At GEB, he was part of a22-member team to commission unit number five ofUkai Thermal Power Station, Gujarat. Since 1986, he

has been with Birla Vishvakarma Mahavidyalaya Engineering College, VallabhVidyanagar, India, first as a Lecturer and from 1990 onwards as an AssistantProfessor. His areas of interest are power system protection and operation.

Sukumar M. Brahma (S’00–M’04) was born inAhmedabad, India, in 1966. He received the B.Eng.degree from Lalbhai Dalpatbhai College of Engi-neering, Ahmedabad, India, in 1989, the M.Tech.degree from the Indian Institute of Technology,Bombay, India, in 1997, and the Ph.D. in electricalengineering from Clemson University, Clemson, SC,in 2003.

From 1990 to 1999, he was a Lecturer in theElectrical Engineering Department with BirlaVishvakarma Mahavidyalaya Engineering College,

Vallabh Vidyanagar, India. He is presently an Assistant Professor at WidenerUniversity, Chester, PA. His research interests are power system analysis,protection, and operation.

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