IEEE Power System Paper-STATCOM Impact Study on the Integration of A

226 IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 23, NO. 1, MARCH 2008

STATCOM Impact Study on the Integration of aLarge Wind Farm into a Weak Loop Power System

Chong Han, Member, IEEE, Alex Q. Huang, Fellow, IEEE, Mesut E. Baran, Member, IEEE,Subhashish Bhattacharya, Member, IEEE, Wayne Litzenberger, Senior Member, IEEE, Loren Anderson,

Anders L. Johnson, Member, IEEE, and Abdel-Aty Edris, Senior Member, IEEE

AbstractRecently, renewable wind energy is enjoying a rapidgrowth globally to become an important green electricity source toreplace polluting and exhausting fossil fuel. However, with wind be-ing an uncontrollable resource and the nature of distributed windinduction generators, integrating a large-scale wind-farm into apower system poses challenges, particularly in a weak power sys-tem. In the paper, the impact of static synchronous compensator(STATCOM) to facilitate the integration of a large wind farm (WF)into a weak power system is studied. First, an actual weak powersystem with two nearby large WFs is introduced. Based on the fieldSCADA data analysis, the power quality issues are highlighted anda centralized STATCOM is proposed to solve them, particularlythe short-term (seconds to minutes) voltage fluctuations. Second,a model of the system, WF, and STATCOM for steady state anddynamic impact study is presented, and the model is validated bycomparing with the actual field data. Using simulated PV and QVcurves, voltage control and stability issues are analyzed, and the sizeand location of STATCOM are assessed. Finally, a STATCOM con-trol strategy for voltage fluctuation suppression is presented anddynamic simulations verify the performance of proposed STAT-COM and its control strategy.

Index TermsImpact study, static synchronous compensator(STATCOM), voltage fluctuation, voltage stability, wind farm(WF).

I. INTRODUCTION

R ECENTLY, mainly due to the technology innovation andcost reduction, renewable wind energy is enjoying a rapidgrowth globally to become an important green electricity sourceto replace polluting and exhausting fossil fuel. The wind turbineswith 23-MW capability have already been commercially avail-able and a 5-MW wind turbine also will be available in a fewyears. Moreover, the cost of wind energy has been reduced to4.5 cents/kWh and is very competitive against conventional fu-els, and will be further reduced to 3 cents/kWh for utility-scalewind energy onshore and 5 cents/kWh offshore by 2012 [1], [2].Additionally, public policy is fostering further integration ofwind energy into the power system.

Manuscript received July 12, 2006; revised June 30, 2006. This work wassupported in part by the U.S. Electric Power Research Institute, in part by theTennessee Valley Authority, in part by the U.S. Department of Energy, and inpart by the Bonneville Power Administration. Paper no. TEC-00241-2006.

C. Han, A. Q. Huang, M. Baran, and S. Bhattacharya are with the Semi-conductor Power Electronics Center (SPEC), North Carolina State University,Raleigh, NC 27695 USA (e-mail: [email protected]).

W. Litzenberger, L. Anderson, and A. Johnson are with Bonneville PowerAdministration (BPA), Portland, OR 97208-3621 USA.

A.-A. Edris is with the Electric Power Research Institute (EPRI), Palo Alto,CA 94304 USA.

Digital Object Identifier 10.1109/TEC.2006.888031

However, with wind being a geographically and climaticallyuncontrollable resource and the nature of distributed wind in-duction generators, the stability and power quality issues of inte-grating large wind farm (WF) in grid may become pronounced,particularly into a weak power system.

Conventionally, the low-cost mechanical switched cap (MSC)banks and transformer tap changers (TCs) are used to addressthese issues related to stability and power quality. However, al-though these devices help improve the power factor of WF andsteady-state voltage regulation, the power quality issues, such aspower fluctuations, voltage fluctuations, and harmonics, cannotbe solved satisfactorily by them because these devices are notfast enough [3]. Moreover, the frequent switching of MSC andTC to deal with power quality issues may even cause resonanceand transient overvoltage, add additional stress on wind tur-bine gearbox and shaft, make themselves and turbines wear outquickly and, hence, increase the maintenance and replacementcost [4]. Therefore, a fast shunt VAR compensator is needed toaddress these issues more effectively, as has been pointed out inmany literatures [2], [4][7].

The static synchronous compensator (STATCOM) is consid-ered for this application, because it provides many advantages, inparticular the fast response time (12 cycles) and superior volt-age support capability with its nature of voltage source [8]. Withthe recent innovations in high-power semiconductor switch,converter topology, and digital control technology, faster STAT-COM (quarter cycle) with low cost is emerging [9], which ispromising to help integrate wind energy into the grid to achievea more cost-effective and reliable renewable wind energy.

In this paper, the effectiveness of a STATCOM in facilitat-ing the integration of a large WF into a weak power systemis presented. Firstly, an actual weak power system with twonearby large WFs is introduced. Based on the field supervisorycontrol and data acquisition (SCADA) data analysis, the issuesare highlighted, and steady state and dynamic voltage controlsare needed to solve these issues. A STATCOM is proposed fordynamic voltage control, particularly to suppress the short-term(seconds to minutes) voltage fluctuations. Secondly, a model ofthe system, WF and STATCOM for steady state and dynamicimpact study is developed in the PSCAD/EMTDC simulationenvironment. The developed model is validated by using thefield data. Moreover, based on the real powervoltage (PV) andvoltagereactive power (VQ) curves obtained from the simula-tion, the system voltage control and stability issues are analyzed,and the size and location of STATCOM are assessed. Finally, aSTATCOM control strategy for voltage fluctuation suppression

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HAN et al.: STATCOM IMPACT STUDY ON THE INTEGRATION OF A LARGE WIND FARM 227

is presented, and the dynamic simulations are used to verify theperformance of the proposed STATCOM and its control strategy.

II. SYSTEM DESCRIPTION

Fig. 1 shows the diagram of the system investigated in thispaper. The two WFs, WF1 and WF2, are connected to the ex-isting 69-kV loop system at bus 3 and 5. The system is suppliedby the two main substations, which are represented by threeremote boundary equivalent sources at bus 1, 2, and 12. Amongthem, bus 1 is a strong bus with a short-circuit capacity of about4000 MVA. The WF2 at bus 3 is a large WF with a total ratingof 100 MVA. It is a type C WF [2] with variable-speed doublefed induction generators (DFIGs) and partial back-to-back con-verters. The WF1 at bus 5 is located at the middle of the weak69-kV subtransmission system, and the short-circuit capacity atthe bus 5 is about 152 MVA. The WF1, with a total rating of 50MVA, is a type A WF [2] using fix-speed squirrel-cage inductiongenerators (SCIGs). The six loads tapped on the 69-kV weakloop system are mostly rural radial loads. The loop network isnormally kept closed to improve the reliability of power supply.

The integration of WF2 into the grid is facilitated by thepower-converter-based interface as it provides VAR compen-sation capability and, hence, voltage control capability. On theother hand, the WF1 poses a challenge, as the SCIGs sink moreVARs when they generate more real power, the generated windpower is rapidly fluctuating with uncontrollable wind speedand large surge current during frequent startups of wind tur-bines. Thus, when WF1 is located at the weakest part of theloop system, these characteristics of WF1 not only increases thetransmission and distribution losses, reduces the system voltagestability margin, and limits power generation, but also causessevere voltage fluctuations and irritates the customers in the sys-tem, particularly in the weak 69-kV loop, where a significantportion of the loads are induction motors, which is sensitive tovoltage fluctuations.

To reduce the voltage fluctuations and improve power factor,small size MSCs (hundreds kilovar) are installed at each individ-ual SCIG terminal and large size MSCs (12 Mvar) are installedat bus 6, the 35-kV secondary side of the WF1 main transformerT3. Moreover, to provide voltage support, all the main trans-formers T1T4 and many customer transformers have severaltaps, and two additional MSCs (2.75 Mvar each) are installed atbus 8. However, because of slow response time, these devicesdo not satisfactorily address the dynamic issues of WF1, andeven exacerbate them.

Fig. 2 shows the selected power injection and voltage profiledata at WF1, monitored during a typical three-day operation.The sampling rate of the data is 5 min. In Fig. 2(a), this profilecovers a WF1s whole operating process, from idle (no windgeneration) to full-rated power output of 50 MW and back toidle. As Fig. 2(b) indicates, the power factor of WF1 is usuallyvery high, about 0.99 lagging, which is fulfilled by controllingthe MSCs at individual SCIGs and bus 6, as long as the gen-erated wind power is larger than about 1 MW. The figure alsoshows that, when the system is idle, WF1 produces 12 Mvar(capacitive) because of the shunt capacitance of the underground

cables connecting individual wind turbines to the common bus6. Fig. 2(c) indicates that the voltage fluctuation at bus 5 is about1.4% during this period. The year-round monitored data indi-cates that this is the case most of the time, although 5% voltagefluctuation sporadically happens from time to time. There is alsovoltage fluctuation even without any WF1 generation, whichmeans that the voltage fluctuations of local system are not onlycaused by generated power fluctuation of WF1, but they arealso contributed by WF2 and voltage fluctuations at the remoteboundary buses. Therefore, a single STATCOM using emitterturn-off (ETO) thyristor [10] and cascaded-multilevel converter(CMC) [11] is proposed to suppress the voltage fluctuations ofthe weak loop system.

III. MODELING AND CONTROL

In this section, the modeling, PSCAD implementation andvalidation of the studied 12-bus power system, WF, and STAT-COM are presented.

A. Twelve-Bus System Model

The system shown in Fig. 1 is modeled using PSCAD/EMTDC. Since only balanced operation is considered for thisstudy, the positive-sequence dynamic model is developed. Someof the details include the following.

Boundary equivalent source is modeled as ideal voltagesources with series equivalent impedances.

Transmission lines are represented by their equivalent model.

Transformer is implemented using the PSCAD classicaltransformer modeling approach and including the leakageinductance and resistive loss.

Loads are considered as constant power. Only one loadprofile is considered. Data for the monitored loads are ob-tained from the SCADA, and for the nonmonitored loads,they are assumed to be 30% of their supply transformerrating.

B. WF Model

Since the focus in this paper is on the system impact studyof electrical power flow and voltage, the implemented model ofthe WFs does not include mechanic dynamics and the detailedelectrical model of induction machine [6], [12], and it is an idealvoltage source with equivalent series and shunt impedance. Forsuch a WF model, the following assumptions have to be made.

All wind turbines are identical. Wind speed is uniform, so that all wind turbines share the

same power generation. Each turbine runs at the same operating modes at all times,

and the voltages, current, and power factor of each turbineare the same.

The series equivalent impedances of underground cablesthat connect the SCIGs to the common bus 6 are negligible.

All transformers connecting individual SCIGs areidentical.



Fig. 1. One-line diagram of the studied system.

Fig. 2. Field SCADA data of WF typical operation.

With these assumptions, both WF1 and WF2 are modeled as aquasi-dynamic model so that all the real power, reactive power,and voltage of WFs are dynamically controlled to recur thesystem operation from the field SCADA data for an operatingpoint for steady-state study and a continuous period for dynamicstudy, where the real power of WF is controlled by the sourcephase angle, the reactive power of WF is controlled by a shuntcap bank at 35 kV bus of WFs, and the bus voltage of WF iscontrolled by the source voltage.

From the three-day data in Fig. 2, a 6-h period data of theWF1 typical low power generation, which represents smalleramount of turbine online and the weakest grid connection ofWF1, is selected for study. This case corresponds to operationof eight turbines out of total 83 turbines in WF1. To account forthe VAR contribution of the underground cables, a 2.06-Mvarshunt capacitor is added at the 34-kV interface bus 6.

Fig. 3. Comparison of simulation results and field data at an operating point.

C. Model Validation

First, a specific operating point in 6-h period is selected.By tuning the boundary sources, WFs and the nonmonitoredloads, this operating point is simulated on PSCAD/EMTDC.The results, given in Fig. 3, match the field data quite well.Therefore, the 12-bus system model with WFs at the specificoperating point is validated.

To simulate the operation of the system during 6-h period, themodel is closed-loop controlled by proportionalintegral (PI)controllers in order to match with the monitored data. Therefore,a whole continuous period operation of the studied system canbe fully recurred in the off-line PSCAD simulation.

The time-domain simulation results for this 6-h period aregiven in Fig. 4 together with the actual data, where the units ofreal power, reactive power, and voltage are, respectively, MW,Mvar, and p.u., which is the same for the units in the later systemsimulation results. In general, compared to the field data, thesimulated real power, reactive power, and voltage follow almostthe same fluctuation trend and magnitude, and also have goodmatch in terms of the steady-state values. Therefore, the systemmodels in a continuous operation period are validated and can beused for dynamic STATCOM impact study in the next section.



Fig. 4. Comparison of simulation results and data for a 6-h operation. (a) Bus2 voltage and power flow from bus 2 to 3. (b) Bus 3 voltage and power flowfrom WF2. (c) Bus 4 voltage and power flow from bus 4 to 5. (d) Bus 5 and 6voltage and WF1 power output at bus 5 and 6.

Fig. 5. Proposed STATCOM and its controller. (a) Generalized CMC-basedY-connected STATCOM schematic. (b) Internal control strategy of CMC-basedSTATCOM.

Moreover, some insights can also be pointed out from Fig. 4as follows.

The mismatch at the beginning of each waveform is be-cause of the simulation initialization transient, which is thesame for the later time domain simulation results and willnot be mentioned again.

For the real power in Fig. 4(a) and (c), there is some slightlyincreasing mismatch between the simulation results andfield data, which is because this period is close to midnightand the actual loads gradually decrease, while the simulatedloads are all modeled as fixed loads.

For the voltages in Fig. 4(b) and (c), there is a small steady-state offset between the simulation results and field data,though the simulation results follow almost the same fluc-tuation trend and magnitude while compared to the data.This could be because the TC settings of some transformersare unknown and not included into the model.

In Fig. 4(d), because of the T3s reactance, there is a con-stant offset between reactive power at 35-kV bus 5 and69-kV bus 6, and a slightly higher voltage profile at bus 5than bus 6.

D. STATCOM Model and Control

The proposed STATCOM uses a CMC-based topology, asshown in Fig. 5(a). For this study, a harmonics-free dynamicmodel of the CMC-based STATCOM with its internal control,



Fig. 6. Simulation results of the CMC-based STATCOM model.

as shown in Fig. 5(b), is implemented on PSCAD/EMTDC [9],[11], [13].

The simulated results, as shown in Fig. 6, illustrate how theSTATCOM shown in Fig. 5(a) responds to step change com-mands for increasing and decreasing its reactive power output,where the units of dc voltage, reactive current, ac voltage, acoutput current, and reactive power output are kV, kA, p.u., p.u.,and Mvar, respectively. As the figure illustrates, the reactivecurrent step change response has a bandwidth as fast as a quar-ter cycle, and 10 Mvar is generated by the STATCOM, andthe average dc capacitor voltage of about 1.5 kV is dynami-cally controlled and does not change due to the VAR commandchange. Therefore, the STATCOM model is validated.

IV. SIMULATION AND ANALYSIS

With the validated system model at the specific operatingpoint, the PV and VQ curve [14][16] of WF1 at bus 5 is ob-tained through the steady-state simulations, as shown in Fig. 7.

First, the PV curve at bus 5, where WF1 is connected tothe system, is obtained by regulating the WF1 source angleto increase the real-power injection at this bus while keepingthe rest of the system constant. Fig. 7(a) shows the PV curveobtained with the nose point of the PV curve located around(32 MW, 0.88 p.u.). It means that, provided that the WF1 injectsunity power-factor power at the operating conditions simulated,there is about 30 MW real power injection margin at this bus forvoltage stability, which is already far beyond the total rating ofeight online turbines, 4.8 MW, at the specific operating point.Moreover, MSCs at WF1 work as power-factor compensatorand can further improve the PV curve and extend the WF1power-injection margin from voltage stability point of view [7].Therefore, the voltage stability is not a serious issue for thestudied loop system, and STATCOM, utilizing its fast responsefor a cost-effective application, can focus on solving the dynamic

Fig. 7. Steady-state simulation results. (a) PV curve. (b) VQ curve.

voltage-fluctuation issue rather than to regulate the steady-statevoltage profile.

Actually, from technology point of view, the most effectivelocation to install STATCOM to suppress the voltage fluctuationrelated to WF1 is just directly at the WF1s point of commonpoint (PCC), which is at 69-kV bus 5. In Fig. 7(b), VQ curveobtained by injecting VAR at bus 5, evaluates the size of STAT-COM. This curve indicates that there is no voltage stabilityproblem at the operating point again, but the sensitivity of thebus voltage to VAR injection is quite high; 10-Mvar injec-tions can cause about 5% voltage change at the bus. Fromthe year-round data, the most severe voltage fluctuation, whichhappens rarely, is about 5%, and most voltage fluctuation isless than 1.5%. STATCOM voltage control capability shouldcover not only typical 1.5% cases, but also the most severe5% case. Therefore, a 10-MVA STATCOM is a reasonablesize to suppress voltage fluctuations at bus 5 covering the mostsevere 5% case, and a STATCOM with the size of 5 MVA isenough to suppress voltage fluctuation for typical 1.5% cases.

Although bus 5 seems an effective location for STATCOM,if STATCOM can be installed inside the substation at bus 6, asshown in Fig. 1, from the practical cost-effectiveness point ofview, the additional space for STATCOM need not be plannedand the civil works can be significantly reduced so that thecost can be significantly lowered. To compare the STATCOMvoltage control capability at different locations, the simulationresults with STATCOM, respectively, installed at bus 5 and bus6 are shown in Fig. 8, where the solid line is with STATCOMat 69-kV bus 5, and the dotted line is with STATCOM at 35-kVbus 6. As seen from the waveforms, whatever be the capacitive



Fig. 8. STATCOM voltage control capability versus location. (a) CapacitiveVAR versus bus 5 voltage. (b) Inductive VAR versus bus 5 voltage.

Fig. 9. STATCOM external controller for voltage fluctuation suppresion.

VAR to improve voltage or inductive VAR to depress voltage,STATCOM at 35-kV bus 6 has almost the same voltage con-trol capability as STATCOM at 69-kV bus 5, and the voltagedifference between the two locations increases with increas-ing |Q |. This voltage difference is just 0.005 p.u., even atmaximum/minimum STATCOM output 10 Mvar. Therefore,a 10-MVA STATCOM installed at 35-kV bus 6 is still able tosuppress voltage fluctuations at bus 5 covering most severe5%case, and a STATCOM with the size of 5 MVA is still enough tosuppress voltage fluctuation for typical 1.5% case. Therefore,considering cost-effectiveness, bus 6 can also be the choice forSTATCOM location.

Another simulation has been performed to make a preliminaryassessment of the impact of the STATCOM on the system. Thissimulation involved dynamic operation of the STATCOM at bus6 during the 6-h monitoring period. The proposed STATCOMexternal control for voltage fluctuation suppression is shownin Fig. 9. The dc value of bus rms voltage is substracted frommeasured rms voltage, equivalent to feed through a washoutfilter, so that only the voltage fluctuation part is used as the in-put to voltage loop controller. Therefore, STATCOM can adap-tively deal with voltage fluctuation, independent from systemsteady-state voltage regulation by operations of MSCs and TCs.

Fig. 10. Comparison of voltage fluctuations with or without STATCOM.(a) Bus 2 voltage. (b) Bus 3 voltage. (c) Bus 4 voltage. (d) Bus 5 and 6 voltage.(e) Bus 8 voltage. (f) Bus 11 voltage.

An additional benefit of this external scheme is, with well-designed fast voltage bandwidth utilizing the fast switching ca-pability of ETO switches and the synthesization characteristicsof CMC topology, even the relatively faster voltage fluctuationsand flicker [13], [17], [18], due to the switchings of MSCs, bladepassing tower [5], SCIG startup and so on, could be suppressedautomatically together with the short-term (seconds to minutes)voltage fluctuations.

Fig. 10 gives the simulation results using STATCOM with itscontrol strategy for voltage fluctuation suppression, where thesolid line is without STATCOM and the dotted line is with STAT-COM. The STATCOM is located at 35-kV bus 6. As clearly seenfrom Fig. 10(a) and (b), bus 2 and 3 is almost unchanged evenwith STATCOM, which is obvious because they are closelyconnected to a very strong bus 1 with the low impedance of T1



and the short 115 kV-transmission line. In the Fig. 10(d), bus5 voltage fluctuation is almost fully solved, so is bus 6. Thereason why voltage fluctuations at bus 6 are a slightly largerthan bus 5 in the case with STATCOM is that the STATCOMcontrol reference is not bus 6 voltage but bus 5 voltage, thoughSTATCOM is installed not on bus 5 but on bus 5. As shown inthe Fig. 10(c), (e), and (f), the voltage fluctuation at other 69-kVbuses are all suppressed considerably as well, and the extents ofsuppression are dependent on how these buses are close to bus5, as the suppression is more at the close bus 4 and 8, and less atthe far bus 11. Therefore, these dynamic simulation results ver-ify the previous analysis and assessment based on steady-statePV and VQ curves, and the effectiveness of STATCOM and itscontrol strategy for voltage fluctuation suppression.

In addition, since the STATCOM suppresses the voltage fluc-tuation, it is apparent that, compared to the case without STAT-COM, the switching times of MSCs and TCs of both main trans-formers and load transformers to address the voltage fluctuationissue in the system shall be significantly reduced. Therefore,the maintenance and replacement cost of MSC, TC, and windturbines can be lowered, and the power quality issues related tothe switching of MSCs and TCs can also be lessened.

V. CONCLUSION

This paper describes the methodology to conduct an impactstudy of a STATCOM on the integration of a large WF into aweak loop power system. The specific issues and solutions ofthe studied WF system are illustrated. For the system study, themodels for the system, WF and STATCOM are developed, andthe system model has also been validated with field data.

From obtained PV and VQ curves from the simulation, thesize and location of STATCOM and the system stability areassessed. It indicates that while low-cost MSCs and TCs boostthe steady-state voltage locally but are ineffective to suppressthe voltage fluctuations (seconds to minutes) due to their natureof slow dynamic response, a 10-Mvar STATCOM, which is asmall percentage of WF rating, can not only effectively suppressthe voltage fluctuations of the WF and the whole 69-kV loopsystem, but also inherently reduce the operation times of MSCsand TCs in the system so that the maintenance and replacementcost of MSCs, TCs, and wind turbines can be reduced, andthe power quality issues related to the switching of MSCs andTCs can also be lessened. The results also show the location ofSTATCOM selected at 35-kV bus 5 can be a good tradeoff fromcost-effectiveness point of view.

For this specific application of suppressing the voltage fluctu-ations, the dynamic simulation results for a continuous operationperiod also verify the effectiveness of the proposed STATCOMand its control strategy, which can adaptively deal with voltagefluctuation, independent from system steady-state voltage reg-ulation by operations of MSCs and TCs, and even mitigate thefaster voltage fluctuations and flicker emission, possibly fromWFs with well-designed fast control bandwidth. Therefore, it isconcluded that the installation of a 10-Mvar STATCOM systemis effective for integrating the specific WF into the weak looppower system.

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Chong Han (M07) received the B.S.E.E. (Hons.)degree from Huazhong University of Science andTechnology (HUST), Wuhan, China, and the M.S.degree from Virginia Polytechnic Institute and StateUniversity, Blacksburg, VA. He is currently work-ing toward the Ph.D. degree at North Carolina StateUniversity (NCSU), Raleigh, NC, all in electricalengineering.

From 1999 to 2001, he was with the NationalTransient Network Analyzer (TNA) Laboratory andSuperconductivity Power R&D Center, HUST, where

his research focused on FACTS controller, energy storage system, and powersystem automation. From 2001 to 2004, he was a Research Assistant at the Cen-ter for Power Electronics Systems (CPES), Virginia Tech. From 2004 to 2006,he was with the Semiconductor Power Electronics Center (SPEC), NCSU. Cur-rently, he is with ABB Inc., Raleigh, NC, as a Grid System Consultant. Hiscurrent research interests include control of power electronics and power sys-tem, real-time simulator, energy storage system, and renewable energy.



Alex Q. Huang (S91M94SM96F05) was bornin Zunyi, Guizhou, China. He received the B.Sc. de-gree from Zhejiang University, Hangzhou, China, in1983 and the M.Sc. degree from the Chengdu Insti-tute of Radio Engineering, Sichuan, China, in 1986,in electrical engineering, and the Ph.D. degree fromCambridge University, Cambridge, U.K., in 1992.

Since 1983, he has been involved in the devel-opment of modern power semiconductor devices andpower integrated circuits. He fabricated the first IGBTpower device in China in 1985. He is the inventor and

key developer of the emitter turn-off thyristor technology. From 1992 to 1994,he was a Research Fellow at Magdalene College, Cambridge. From 1994 to2004, he was a Professor at the Bradley Department of Electrical and ComputerEngineering, Virginia Polytechnic Institute and State University, Blacksburg,VR. Since 2004, he has been the Alcoa Professor of Electrical Engineering atNorth Carolina State University, Raleigh. His current research interests includeutility power electronics, power management microsystems, and power semi-conductor devices. He is the author or coauthor of more than 100 publishedpapers in international conferences and journals, and also a holder of 14 U.S.patents.

Dr. Huang is the recipient of the NSF CAREER Award and the prestigiousR&D 100 Award.

Mesut E. Baran (S87M88) received the Ph.D. de-gree from the University of California, Berkeley, in1988.

He is currently an Associate Professor with NorthCarolina State University, Raleigh. His research in-terests include distribution and transmission systemanalysis and control.

Subhashish Bhattacharya (M85) received the B.E.(Hons.), M.E., and Ph.D. degrees in electrical en-gineering from the University of Roorkee (IIT-Roorkee), India, in 1986, Indian Institute of Science(IISc), Bangalore, India, in 1988, and the Universityof Wisconsin, Madison, in 2003, respectively.

From 1994 to 1996, he was with York InternationalCorporation for commercialization of his active fil-ter Ph.D. research work for air-conditioner chillerapplication. From 1996 to 1998, he was a Consul-tant to Soft Switching Technologies (SST), where he

worked on active filters and resonant link converters. From 1998 to 2005, hewas in the FACTS and Power Quality Division of Siemens Power Transmissionand Distribution. Since August 2005, he has been an Assistant Professor in theDepartment of Electrical and Computer Engineering at North Carolina StateUniversity, Raleigh, where he is also a Faculty Member of the SemiconductorPower Electronics Center (SPEC). His research interests include FACTS, util-ity applications of power electronics such as custom power and power qualityissues, active filters, high-power converters, and converter control techniques.

Dr. Bhattacharya has been involved in several FACTS projects, including theNew York Power Authority (NYPA) 200 MVA Convertible Static Compensator(CSC), the KEPCO-Korea 40 MVA UPFC, and the American Electric Power(AEP) 150 MVA STATCOM projects.

Wayne Litzenberger (M73SM00) received theB.S.E.E. and M.S.E.E. degrees from the Universityof Washington, Seattle, in 1963 and 1969, respec-tively.

He was briefly with the Boeing Company in Seat-tle. Since 1989, he has been with Bonneville PowerAdministration (BPA), Portland, OR and Vancouver,WA, where most of his assignments were related toHVDC and FACTS projects.

Mr. Litzenberger has been active in the Power En-gineering Society, holding a number of offices in the

T&D and Substations Committees. He was the U.S. Representative to CigreStudy Committee B4 from 2002 to 2004.

Loren Anderson received the B.S. degree from Oregon State University,Corvallis, in 1980.

Currently, he is the Principal HVDC and FACTS Engineer at the BonnevillePower Administration (BPA), Vancouver, WA. He has vast experience workingon HVDC systems. His research interests include HVDC control design, equip-ment maintenance, and failure analysis.

Anders L. Johnson (M02) received the B.S.E.E.and M.S.E.E. degrees from the University of Wash-ington, Seattle, in 2002 and 2003, respectively. Hewas also a Grainger Graduate Fellow.

Since 2002, he has been an Electrical Engineer atthe Bonneville Power Administration, Portland, OR.His research interests include electromagnetic tran-sients simulation, protective relaying, high-voltageequipment, and power electronics applications to thetransmission grid.

Abdel-Aty (Aty) Edris (SM88) was born in Cairo,Egypt. He received the B.S. (Hons.) degree fromCairo University, Cairo, Egypt, the M.S. degree fromAin-Shams University, Cairo, and the Ph.D. degreefrom Chalmers University of Technology, Goteborg,Sweden.

He was with the ABB Company in Sweden andUSA for 12 years, where he was involved in the de-velopment and application of reactive power com-pensators and high-voltage dc transmission systems.Since 1992, he has been with Electric Power Research

Institute (EPRI), Palo Alto, CA, as a Manager of Flexible ac Transmission Sys-tem (FACTS) technology, where he is currently the Technology Manager ofEPRI Power Delivery and Markets.

Dr. Edris is a member of several IEEE and CIGRE Working Groups and therecipient of the 2006 IEEE FACTS Award.


Documents

IEEE Power System Paper-STATCOM Impact Study on the Integration of A