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548 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 24, NO . 4, IULYIAUGUST 1988

Considerations for Ground Fault Protection inMedium-Voltage Industrial andCogeneration SysternsAbstract-Industrial plants utilize med ium-v oltage system s for in-plant

distribution of purchased and cogenerated electrical energy. During theplanning stage, system protection is generally specified, including th e typeof source neutral grounding and ground fault protection. Where medium-voltage systems have expanded, circuit-breaker interrupting ratings havealso been increased. Accordingly, grounding consideration should bereviewed, particularly because charging and/or ground fault currentvalues have also increased. The typical methods for grounding ofmed ium-v oltage neutral systems-high resistance, low resistance, andungrounded, as well as methods used to detect the presence of a groundfault-are reviewed. Also , the effects of charging current and how theground fault protection method could affect conductor ratings areanalyzed.

I. INTRODUCTIONHE application of grounded systems developed becauseTengineers realized that delta (ungrounded) systems permitdamages due to overvoltages caused by system or equipmentfaults to ground. The question of which type of groundedsystem to use depends upon the plant process, and frequentlythe only factor evaluated is whether or not the owner wants tocontinue process operation, even after a ground fault has beendetected. This continuity of operation is the principal argu-ment used by advocates of a delta or high-resistance groundedneutral approach, assuming that the system is later shut downbefore the electrical fault causes serious damage. This fault

damage limitation becomes the crux of the decision making.11. SYSTEM(NEUTRAL)GROUNDING

This is the heart of any system design, as well as a criterionfor designing the protection system. In the context of systemgrounding, one must be certain to agree that this term relatessolely to how the source is grounded and not to any otherterms, such as grounding of metallic structures or conduits toan equipotential grid for purposes of providing ground currentpaths for personnel safety purposes.A classic statement relates that there is no such conditionas an ungrounded power system, because each current-carrying conductor is insulated from other conductors andPaper IPCSD 86-32, approved by the Power Systems Protection Committeeof the IEEE Industry Applications Society for presentation at the 1986Industry App lications Society Annual Meeting, Denver, CO , Septem ber 28-October 3. Manuscript released for publication Octob er 23, 1987.D. J. Love is at 3002 Hacienda Boulevard, Hacienda Heights, CA 91745.N. Hashemi is with Bechtel Western Power Corporation, P.O. Box 2374,IEEE Log Number 8820189.La Habra, CA 90632.

ground (earth) by air or some form of solid insulation. Eachform of insulation has characteristics that can be defined interms of resistance and capacitance, such as in cables.Naturally the resistance (insulation resistance) is extremelyimportant, because this is the barrier effect of the dielectricwhich keeps the current-carrying conductor essentially iso-lated from other conductors of electricity. The capacitivecurrent, on the other hand, does not serve a useful function,although it does have predictable magnitudes in cables,electric machinery, transformers, and surge capacitors appliedto protect motors and transformers [ I ] . Thus all systems aregrounded, even if only through capacitive means.System grounding is the single most important element inthe design of the industrial power system, and many compan-ies have standardized practices that have been proven to workwell for the environment in which the company operates. Still,cases exist where standards are applied without the benefit ofcomparing them against new circumstances, and this could bea mistake, even if it did save engineering manhours. Expan-sion of the medium-voltage system for cogeneration is oneexample.111. MEDIUM-VOLTAGESYSTEM(1000-15 OOO V)

Let us examine what happens when we select a delta, a high-resistance grounded neutral, or a low-resistance groundedneutral, because it is rare that an industrial design would use asolidly grounded neutral system intentionally, although thismay happen when the utility and the designer of the plantdistribution system do not communicate properly.The delta system should always have a ground detector incontinuous operation on the system, because even the bestdesigned power distribution system will be exposed to failuresin equipment due to natural causes, design or construction ofthe equipment, or flawed installation. Of all the systemdesigns, the delta requires high maintenance because it has nomeans to limit overvoltages that may occur subsequent to aground fault.A ground fault detector will indicate that a ground faultexists but cannot identify the location of the ground fault. So itis necessary to open feeders and determine on which feeder theground fault exists. The next question is whether this groundfault can be detected before the ground fault turns into a phase-to-phase fault after a second phase becomes grounded, nodoubt assisted by the increase of 73-percent voltage betweenthe second phase and ground. It would do no good to shut

OO93-9994/88/07OO-0548$01.OO O 1988 IEEE

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LOVE AN D HASHEMI: GROUND FAULT PROTECTION IN MEDIUM VOLTAGE SYSTEMS 549down the system upon detecting the first ground fault becausethis would defeat the main advantage of the delta system-thatis, it could remain on-line until it is convenient for operationsto shut it down for maintenance.Other systems mentioned would have means to limitovervoltages and, in varying degrees, to identify the branch inwhich the ground fault exists. The low-resistance groundedneutral may permit high levels of ground fault current (500-1500 A, i.e.) to flow and facilitate selective tripping, whereasa high-resistance grounded neutral would limit the groundfault current to - 10 A, with detection by branch-circuitcurrent relays, neutral voltage relay, or some special pulsegenerators [2].One of the factors in deciding on a system groundingmethod depends upon the magnitude of the charging current.A . Charging Currents

One way to understand charging currents is to envision amedium-voltage ungrounded system of one motor load withsurge capacitors. In addition to the surge capacitors there iscapacitance within the motor (turn-to-turn as well as turn-to-ground) and in the cable between the conductor and the shield.Only the capacitance of the surge capacitors has been shown inFig. 1, for purposes of clarity. Note that the capacitor currentphasors lead the respective phase voltages by 90". Because ofthe assumed balanced nature, the sum of the capacitor currentsequals zero.Assuming a 13.2-kV motor, the capacitors at the motorwould normally draw 0.75 A, each as shown in Fig. 1 as lac ,Ibc, and ICC.When phase B becomes grounded, the current ineach other capacitor increases by &, ( l ab ,Icb) . The resultantcurrent to phase B, shown in Fig. 2, becomes equal to 3X theinitial capacitive current, 2.25 A. This 3lc is the chargingcurrent, and each capacitive circuit element has a chargingcurrent component. In this isolated system, the current returnsto the source as shown in Fig. 3. The ground fault relay, 51G,actually measures zero current because the sum of the currentsequals zero.

If the system had a resistance-grounded neutral, the relay51G would sense the current that flows to the system neutral.Fig. 4shows the relative magnitude of this postulated groundfault, using a low-resistance grounded neutral and comparingthe 2.25 A in phase B due to the surge capacitors to the neutralreturn current Zbn equal to approximately 100 A. Relay 51Gwill sense this Ib n and operate accordingly.On the other hand, a high-resistance grounded neutralsystem would require a neutral resistance that produces aneutral fault current equal to or slightly greater than themagnitude of the system charging current. Using the samephasor designations of Fig. 4, Fig. 5 illustrates that theresultant total fault current 2& the charging current.Therefore extensive damages may be permitted by alarm-onlysystems when the charging current approaches 10 A.To appreciate the effects of charging current requires theuse of a systems approach. Fig. 6shows a series of identicallysized motors, each protected by capacitors, with the results ofcharging current due to phase B faulting to ground on themotorMn branch circuit. The charging current on each, motor

A/ I

CAPACITORSGROUND FAULT RELAYAT SWITCHGEAR

SURGECHARGINGPHASORSSHOWINGCAPACITORSTO CURRENTA"A "C

Fig. 1, Normal conditions. No-fault surge capacitors at medium-voltagemotor.B

"AB/ IAB\ "CBIAB=ICE= l I c C IE' = ( 0 . 7 5 ) E'-IB= IAB+ ICB=

IIacI /330' = L ( 0 . 7 5 ) /330'

( 0 . 7 5 ) ( 0 . 8 6 6 - j 0 . 5 + 0.866 + j 0 . 5 )= L ( 0 . 7 5 ) ( L ) = 3 ( 0 . 7 5 ) = 2 . 2 5 A

CHARGING CURRENT I N FAULTED PHASE = 2 . 2 5 AFig. 2 . Phasors for line-to-ground fault showing surge capacitor current.

/ ICE

Fig. 3. Effects of charging current only on ground fault relay of faultedfeeder. Actual fault current would include neutral resistor current.

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550 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 24, NO . 4, JULYIAUGUST 1988

I B N 'CB 4 ,'AB

N-TURNSxFig. 4. Effects of charging current on low-resistance grounded neutralsystem.I F I b n

Fig. 5. Effects of charging current on high-resistance grounded neutralsystem.

IEN+(n-l) IE(NET)(n-l)lE Itn$,-

rf- @ IE PHASETO GROUNDt -LOW RESISTANCE METHOD GROUND GRID

Fig. 6. Ground fault current on system n motors, each with surgecapacitors.M1 to motor Mn - 1, returns to the source, cumulativelyequal to a capacitive current magnitude of (n - 1)Ib. (Thecharging current appears essentially as a capacitive load.) Inthe nonfaulted motor feeders, only I b will be measured byeach 51G relay because there will be no balancing currents Icband lab as there had been in the isolated system of Fig. 3.Thus unfaulted branch circuits will sense what appears to be aground fault.

The current in the branch circuit to motor Mn would beequal to the phasor sum of Zbn and (n - 1) Zb. For example,if n = 8, the phase B fault current in motor M n will be equalto the phasor sum of Zbn (e.g., 100 A) and 7 x 2.25 A: Z =d(100)2 + (7 x 2.25)2 = 101 A. In this case, the capacitivecurrent did not add significantly to the total phase current.Each feeder would conduct only 2.25 A, hardly enough tocause false tripping. Also shown in Fig. 6 is the groundedneutral-a resistor for the low-resistance installation with acurrent relay, device 51G1. Alternatively, for a high-resistanceinstallation, Fig. 6 shows a distribution transformer with aresistor and voltage relay device, 64,paralleled to the trans-former. secondary. Naturally, only one source groundingmethod would be used for any one installation.However, other factors have been ignored, and these couldimpact upon the faulted feeder as well as the unfaulted feeders.For instance, slow-speed motors have high values of chargingcurrent, as can shielded cables, which may be oversized tocompensate for long runs between the switchgear and themotor.Thus individual unfaulted feeders may have chargingcurrents that could affect the branch circuit relay sensitivitywhen a high-resistance grounded neutral system is used.Worse yet is the effect of these charging currents whensummed as in the motor Mn feeder of Fig. 6. The damage atthe fault would be escalated when the resistive neutral current(Zbn) has been limited to a value slightly greater than (n - 1)Ib in order to limit overvoltages, and when the chargingcurrent exceeds 10 A as shown in Fig. 5. There is someexcellent documentation on this damage subject, and theauthors of this paper encourage further reading of some well-documented test results [3], [4].

IV. COGENERATIONINSTALLATIONSTwo examples are shown to illustrate how necessary it maybecome to consider the effects of charging current. Fig. 7

represents an installation where generation has been added to a13.8-kV bus and where the overall system is not extensive. At13.8 kV, the system is grounded through a high resistance atthe generator neutral, tripping the generator breaker withdevice 64G within seconds after detecting a 13.8-kV fault.After generator circuit breaker 52G opens, the 13.8-kV bus ismonitored by device 64B, which will then trip circuit breaker52L in the event that a ground fault persists. At 13.8 kV thedevices should trip and not just alarm [5].In Fig. 7, two transformers reduce the 13.8-kV supplydown to 4160 V and 480 V, respectively. The 4160-V systemis shown to have a low-resistance grounded neutral withautomatic fault tripping, but could have had a high-resistancegrounded neutral with alarm only for ground faults. (See laterdiscussion of 4160 V). The 480-V system is shown to have ahigh-resistance grounded neutral, and while a discussion of itsmerits are beyond the scope of this paper, there are excellentreferences which discuss the subject [6]-[9].In Fig. 8 the 13.8-kV system is more extensive, with thepossibility of a high charging current in excess of 10 A, whichwhen accompanied by a corresponding resistor neutral currentproduces a resulting fault current approaching 20 A. Because

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LOVE AND HASHEMI: GROUND FAULT PROTECTION IN MEDIUM VOLTAGE SYSTEMS 55 1

7 52L 13 .8 KV

Fig. 7. Cogenerationclosely coupled systems with limited plant distributionsystem.

NC

Fig. 8. Cogeneration with extensive plant distribution.

20 A would produce significant damage at the point of fault,the design choice must be a low-resistance grounded neutralsystem that trips rather than alarms. As in the Fig. 7example,the ground fault protection would operate to trip first the tiebreaker and then the respective faulted bus section.A. 4.16-k V High-Resistance Grounded Neutral

Caution is also needed when applying high-resistancegrounded neutrals to 4.16-kV systems. Whereas the chargingcurrent will be considerably smaller than a 13.8-kV system,the desire to continue operations during a ground fault must betempered with the fact that certain cable standards must beobserved, and in general may affect the length of operatingtime during a ground fault.

ICEA Standard S-66-524 applies to cross-linked polyethyl-ene cable and lists among other facts the insulation thicknessrequired versus the system grounding and ground faultprotection system. On 5-kV installations, the following shouldbe noted in Table 3-1.

Insulation LevelRated Voltage 100% and 133% 173%

2001-5000 90 mils consult manufacturer

The 100-percent level is defined as a system in which the

protection clears the fault within 1 min. This is obviously adescription for a solidly grounded neutral or low-resistancegrounded neutral system with ground fault protection andcircuit breakers.

The 133-percent level is defined as a system where there isassurance that the clearing time for the fault does not exceed 1h. The 133-percent level requires that the system be simpleand that ground faults be isolated in the relatively short time of1 h.The 173-percent level applies to those systems where thetime required to de-energize a grounded section is indefinite.This 173-percent level (often referred to as a delta system)therefore requires a higher level of maintenance, and theinsulation thickness is correspondingly greater. In reviewingthe 173-percent with many cable manufacturers, all concludedthat the cable used at the 173-percent level should be rated at 8kV with 140 mils of insulation. From a practical standpoint,few suppliers stock 8-kV cable, and probably 15-kV cablewould be used on the 4.16-kV delta (o r high-resistance)system, which could then operate safely and indefinitely with aground fault.

Therefore a high-resistance approach may be adequate on4.16 kV if the cable is adequate. Similar considerations wouldapply to voltage transformers, which would also require a linevoltage rating, even when applied phase-to-ground on thehigh-resistance system. This bears mention for cogenerationrelay and metering of the generator.

Applying relays to protect this 4.16-kV system shouldinclude a voltage relay across the neutral resistor as aminimum, since this can be used to detect a ground fault in anypart of the system. To gain selectivity it will be necessary toapply sensitive ground fault relays to each feeder set above itscalculated (or measured) feeder charging current. Certainaspects of this selectivity have been covered by other authors,and suffice it to state that new hardware and techniques can beexpected to improve this feature [2], [7].

Assuming that coordination is required for a radial system,the backup relay devices would rely more on time delay thanupon time-current delay due to the practical limitation ofmeasuring sensitivity. Again hardware improvements and newtechniques could always improve the coordination capabilitiesof devices on the high-resistance grounded neutral 4.16-kVsystem.B. Low-Resistance Grounded Neutral System

This is a very common method used for those systems thatmust trip for ground faults. The neutral resistor limits theground fault to a definite value, e.g., 500 A, loo0 A, 1500 A,for a definite period-10 s, 30 s, 1 min, etc. This system ismost practical for 13.8 kV and has the advantage of selectivetripping due to the nature of higher ground fault currents.Caution must be exercised in selecting the resistance valueso as to provide sufficiently for the time-current relationshipneeded for selective tripping, such as may be found on a largeradial distribution system [lo]. It is this selectivity that is themost important advantage of the low-resistance groundedneutral system. Fig. 9 illustrates a scheme based upon theavailability of only one external power source, and where the

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5 5 2 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 24, NO. 4, JULYIAUGUST 1988

E X T E R N A L P O W E R S U P P LY

I TWO T R A N S F O R M E R SE A C H 7. 5 M V A . 2 = 6.25% I

I!!I wiI

' S E C T I O N '! 2 !S E C T I O N '

L O A D L O A DC E N T E R 1 C E N T E R 2

Fig. 9. Partial protection scheme emphasizing ground fault protection.transformer secondaries may be paralleled at times. Theindividual load feeders are each protected for ground faults bydevice 50G, an instantaneous overcurrent relay that is con-nected to the secondary of a core-balance current transformerto sense 10-30 A, after which device 50G trips its respectivebreaker. Failure to clear the fault necessitates backup groundfault protection by device 51N1 to trip the bus tie breaker inorder to isolate the faulted bus section. Device 51N1 has veryinverse tripping characteristics and is connected in the residualcircuit of the bus tie-breaker CT secondaries. After the tiebreaker opens, only devices in that section containing theground fault will be responsive to further backup protection.Device 51N has the same characteristics as device 51N1, isconnected in the residual circuit of each bus supply breaker CTsecondary, and will trip the bus supply breaker with which itis associated (breaker 10or 20 in Fig. 9).Device 51G1 is similar to devices 51N and 51N1, exceptthat it is connected to the secondary of a bushing or windowCT through which the source transformer neutral-to-ground-ing resistor conductor is passed. This CT will sense trueground fault current, and device 51G1 functions to trip theprimary circuit breaker, coordinating with device 51N and thebus supply breakers (see Fig. 10 for CT location).Alternatively, a residually connected device 50N or 5 1Ncould have been used for the 500-hp protection circuit, it beingsensitive in the same range. However, the residual connectionfor protecting the 3000-hp motor would not be quite assensitive. Since a consistent approach in planning the groundfault protection (GFP) coordination is preferred, each loadfeeder should employ device 50G. If the minimum pickup

STRESS CONES

J A CK E TE D CA B LE SC O R E - B A L A N C EC A B L E S H I E L DJ UM P E RE DTOGE THE R,I S O L A T E D F RO M

G R O U N DS HIE LD J UM P ER

B US HING OR S T A T I O NWINDOW CTC U R R E N T-RESISTOR

F L O O R C O N D U I T

l O IA 1 S OURCE NE UTR A L 1 OiB l S H I E L D E D C A B L EFig. 10. Common methods for ground fault current sensing.

current is set at 30 A, protection is extended to 3percent of theneutral winding (Le., 30 A/1000 A x 100% = 3%). A timeovercurrent relay device 51G with extremely inverse charac-teristics would be more appropriate in the neutral when surgecapacitors are used.Fig. 10 has a typical termination of a medium-voltageshielded cable. After the cable is pulled up through the core-balance CT, the cable jacket is removed to expose the shieldingtape or braid. Jumpering the shields together, the connectionto ground is made after this shield lead is brought back throughthe CT. Grounding of the shield is universally made at theswitchgear, and often at cable midpoints, splices, and at theload. This reduces the "touch potential" and also provides apath for the circulating currents. This precaution is necessaryonly if the shield had been pulled through the CT; if the jacketand shield were removed before the cable was passed throughthe CT, the shield ground would not have to be routed throughthe CT.Between cable shield ground connections, a potential existsthat drives a circulating current, often of such magnitudeas to require derating of the cable ampacity. When applyingthe core balance CT, the effects of this circulating currentmust be subtracted from the measuring circuit by the methodillustrated in Fig. 10.For other examples of applying low-resistance neutralgrounding, please see [2], [ 6 ] ,[lo].

V. CONCLUSIONThis paper has presented several aspects of system ground-ing and the limitations of some systems with respect toapplying ground fault protection. Relays cannot preventdamage by themselves, nor can they be applied to compensatefor design deficiencies.There is no one absolute solution to system grounding and/or protection, but judgment can be exercised by considering

some of the major phenomena described herein.1) If the system voltage is 13.8 kV, apply a high-resistancesystem only if the charging current is low and thedetection scheme causes a tripping action, and not analarm only.2) If the medium-voltage system has a low-resistancegrounded neutral, determine both the sensing method

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LOVE AN D HASHEMI: GROUND FAULT PROTECTION IN MEDIUM VOLTAGE SYSTEMS 553

(residual connection versus core balance CTs) and theresistor size [lo].3) If isolated and limited, a delta system may be satisfac-tory, provided that cable voltage-level ratings are satis-

fied and a ground detector continuously monitors thebus. However, a ground fault can lead to overvoltages,even with a ground fault detector system.

4) If it is a delta or high-resistance grounded neutralsystem, check the voltage ratings on the voltage trans-formers. In addition, at 4160 V be certain that the cablevoltage level is satisfied.

5 ) The introduction of a generator on the plant distributionsystem raises serious concerns, particularly if agrounded system already exists [ 5 ] .

6) A great amount of space has been dedicated to thecharging current phenomenon because it has beenoverlooked or misunderstood.

7) Applying residually connected relays is an inexpensiveapproach to ground fault protection on any type ofsystem. However, this inexpensive approach is marginalon low-resistance grounded systems where coordinationis required [lo]. Furthermore, on high-resistancegrounded systems, the sensitivity is extremely low andcoordination may never be achieved [2]. Thereforeextensive planning on relay coordination may be neces-sary on large systems.

ACKNOWLEDGMENTThe authors wish to acknowledge the suggestions made by

Richard A. Schmitter and Fred Y. Tajaddodi of BechtelWestern Power Corporation and Robert L. Smith of GeneralElectric Company.

REFERENCES[ I ] D . S. Baker, Charging current data for guesswork-Free design ofhigh-resistance grounded systems, in Conf.Record 1978 IEEEIndustrial and Commercial Power Systems., pp. 33-38.[2] R. J . Deaton, Limitation of ground-fault protection schemes onindustrial electrical distribution systems, in Conf.Record 1984IEEE-IAS Ann. Meeting, pp. 331-334.F. K. Fox and L. B. M cClung, Groun d fault tests on a high resistancegrounded 13.8 kV electrical distribution system of a modem largechemical plant-Part I, IEEE Trans. Ind. Appl ., vol. IA-IO, no. 5,Sept. /Oct . 1974.L. B. McClung and B. W . Whittington, Grou nd fault tests on a highresistance grounded 13.8 kV electrical distribution system of a modemlarge chemical plant-I 1, presented at the Industrial and Com mercialPower Systems Conf. of the IEEE Industry Applications Society,Milwaukee, WI, May 3, 1972.R. H. McFadden, Grounding of generators connected to industrialplant distribution busses, in Conf.Record 1980 Industrial Commer-cial Power Systems, pp. 83-85.[6] J. R. Dunki-Jacobs, Th e reality of high-resistance grounding, IEEETrans. Ind. Appl. , vol. IA-13, no. 5 , SeptJOct. 1977.[7] B. Bridger, Jr . and W. E. DeHart, High resistance grounding, inConf. Record 1977 IEEE-IAS Ann. Meeting, Oct. 1977.

[3]

[4 ]

[5 ]

[8] R. L. Smith, Jr . , Neutral deriving transformers for grounding low-voltage systems with delta-connected source transformers, in Conf.Record 1981 IEEE-IAS Ann. Meeting, pp. 451-455.[9 ] J . W. Foster, W. D. Brown, and L. A. Pryor, High-resistancegrounding in the cement industry-A users experience, IEEE Trans.Ind. Appl., vol. IA-22, no. 2, pp. 304-309, Ma r./Ap r. 1986.D . J. Love, Ground fault protection for electric utility generatingstation medium voltage auxiliary power systems, IEEE Trans.Power App . Syst., vol. PAS-97, no. 2, pp. 583-586, Mar./A pr. 197 8.[IO]

Daniel J . Love (S49-M52-SM59-F86) wasborn in Fall River, MA, on September 27, 1926. Hereceived the B.S.E.E. and M.S.E.E. degrees fromthe Illinois Institute of Technology, Chicago, andthe M.B.A. degree from California State Univer-sity, Long Beach, in 1951, 1956, and 1974,respectively. He currently resides in HaciendaHeights, CA.He is an independent Consulting Engineer, spe-cializing in electrical systems and design as well asin fire protection. He was with Bechtel PowerCorpo ration, where for 19 years he was involved with generating station andindustrial power systems design as well as holding the position of FireProtection Engineer for several of the nuclear power plants. He spent threeyears in the Mad rid, Sp ain, office of Bechtel as Chief Electrical and Co ntrolSystems Engineer.Mr. Love has been active on both the national and local levels of the IEEE,having gone through the chairs to become the Chairm an of the 1300-memberMetropolitan Los Angeles Section, and subsequently through the chairs tobecome Chairman of the 13 000-member Los Angeles Council. H e haspresented many papers on system design and protection in both the PowerEngineering and Industry Applications Societies. He w as a Chapter Chairm anof the recently revised Buff Book, IE EE Standard 242-1986. He was recentlyelected Vice-cha irman of the Power Systems Protection Co mmittee, which hehad previously served as Secretary. He w as a recipient of the IEE E CentennialMedal and was honored in 1986 with the Outstanding Engineer Merit Awardfrom the Institute for the Advancement of Engineering (IA E). He is a memberof the Instrument Society of America, the National Society of ProfessionalEngineers, the Society of Fire Protection Engineers, and the National FireProtection Association. H e is a Registered Professional Engineer in the Stateof Illinois, a Professional Engineer-Electrical, in the States of Arizona,California, and Louisiana, and a Professional Engineer-Fire Protection, inthe State of California.

Nasrollah Hashemi (S79-MW) received theB.S.E.E. and M.S.E.E. degrees from the Univer-sity of Florida, Gainesville, in 1979 and 1981 ,respectively.He is currently a Staff Electrical Engineer withthe Bechtel Western Power Corporation, LosAngeles, and has responsibility for the design,development, and implementing of computer pro-grams for computer-aided engineering, recentlycompleting a large relational database managementcompu ter program. Previously he had been assignedto a large nuclear power plant as a Field Engineer for computer-basedsystems. Prior to Bechtel he was associated with the Florida Utility ResearchCenter as a Research Associate, with responsibilities for the design anddevelopment of a computer program for power system analysis.Mr. Hashemi has been involved with the Metropolitan Los Angeles Sectionof the IEEE as a Program Coordinator, and is the current Secretary. He is aProfession al Engineer -Electrical, in the State of Califo rnia.