2004 IEEEIPES Transmission 8 Distribution Conference & Exposition: Latin America
1
GCSC - Gate Controlled Series Capacitor: a
New Facts Device for Series Compensation of
. . -.
'lransmission Lines
E. H. Watanabe, Senior Member, IEEE, L. F. W.de Souza, Member, IEEE, F. D. de Jesus,
J. E. R. Alves, Member, IEEE and A. Bianco, Member, IEEE
Abstract - Controllable series compensation is a useful technique to increase tbc efficiency of operation of existing transmission lines and improve overall power system stability. Up to date,
the TCSC is the most adopted solution whenever controllable
series compensation is required. This paper introduces the Gate
Controlled Series Capacitor (GCSC), a novel FACTS device for
series compensation. The principle of operation and some prospective applications of the equipment nre presented. Special
attention is given to the duaIity of the GCSC with the well-known
thyristor controlled renctor, used for sbunt compensation. It is
shown that the GCSC can be more attractive than the TCSC in
most situations. Simulation results illustrate the time response of
the equipment and its ability to control power flow in a transmission line. Finally, technology issues regarding high power self
commutating valves are discussed.
Ztidex TermsScries Compensation, TCSC, GCSC, FACTS.
I. INTRODUCTION
owadays, it is becoming increasingly difficult to build
new transmission lines, due to restrictions regarding environment and financial issues. Besides that, electrical
energy consumption continues to increase, leading to a situation where utilities and independent system operators have ta
operate existing transmission systems much more efficiently
and closer to their stability limits. One important benefit of
FACTS (Flexible AC Transmission Systems) technology is
that it makes it possible to improve the use of the existing
power transmission system and to postpone or avoid the construction of new transmission facilities.
Among FACTS devices, those for series compensation
play an important role in a country as Brazil, where long
transmission lines connect remote hydro-generation plants to
Iarge urban areas. Conventional series compensation, provided
by f i e d capacitor bank, is a useful tool to improve the power
transfer capacity by neutralizing part of the series reactance of
transmission lines [I]. With the new controlled series compensators, it is possible not only to control the power flow
through transmission lines, avoiding power flow loops, but
N
also to improve power system stability, through the fast actuation of its control loops after disturbances. Moreover, recent changes in the power industry throughout the world increased the interest in equipment capable of control power
flow through pre-determined paths, meeting transmission
contract requirements even in highly meshed systems.
Thyristor Controlled Series Compensators (TCSC) were
the first generation of series compensation FACTS devices.
Actually, TCSC may be credited as a cornerstone of FACTS
deveIopment, as the first equipment developed under the
FACTS concept. TCSC are made of a parallel connection of a
capacitor and a thyristor-controlled reactor [2]. In fact, the
TCSC is simply a static voltage controller (SVC) [3] connected in series with a transmission line. The thyristor is its
switching device. Existing TCSC installation in the world and
in Brazil already proved the efficiency and robustness of the
equipment. Although the TCSC is capable of continuously
adjust its reactance, it has the disadvantage of presenting a
parallel resonance between the capacitor and the thyristor
controlled reactor at the fundamental frequency, for a given
firing angle of the thyristor. Also, the variation range of the
reactance presented by the TCSC is somewhat narrow.
This paper presents a novel equipment for controlled series
compensation: the Gate Controlled Series Capacitor (GCSC)
[4]. The GCSC, shown in Fig. 1, based on a concept first introduced by Kurudy et al. [SI, is made simply of a capacitor
and a pair of self-cornmutated semiconductor switches in antiparallel, e.g., the GTO (Gate Tum-off Thyristor) or the IGCT
(Wegrated Gate Commutated Thyristor) [6]. It i s capable of
continuously vary its reactance from zero to the maximum
compensation provided by the capacitor. The GCSC is simpler
E. H. Watauabe and F. D.de Jesus a
n with the Federal University of Rio
de Jaaeiro, Rio de Janeiro, RJ, Brasil( watanahe@ufj.br; fabio@coe,uf?.br).
L. F. W. de Souza and J. E.R. Alves are with Cepel, Rio de Janeiro, RJ.
Brasil (Ifclipe@cepel.br; alves@cepel.br).
A. Bianco is with Andrade e Cauellas Consulting, S a Paulo, SP,Brasil
(andre.bianco@andradecanellas.com.br).
0-7803-8775-9/041$20.00 02004 IEEE
-
Fig. I The Gate ControolledSeries Capacitor 4 C S C .
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-I
90
-
100
110
120
130
140
150
160
170 180
Y (degrees)
Pig. 3 F u n k n t a l impedance of the GCSC as a function of the blocking
angle
ductor switches. This blocking angle y is measured from the
zero crossing of the line current. Fig. 2 shows typical current
Fig. 2 -Typical voltage and current waveforms of the GCSC
and voltage waveforms for the GCSC of Fig. 1, for a given
than the TCSC, utilizes a smaller capacitor, does not need any blocking angle y. It is assumed that the transmission line curreactor and, differently from the TCSC, does not have an in- tent, i,is sinusoidal. In order to avoid dc voltage components
trinsic internal resonance. For these reasons, the GCSC may in the series capacitor, during normal operation, the blocking
be a better solution in most situations where controlled series angle y should be greater than 90" and smaller than 180'.
compensation is required. One potentially interesting applicaFig. 3 shows the relation between the fundamental impedtion of the GCSC is in the retrofitting of existing fixed series ance of the GCSC and the blocking angle y. A blocking angle
capacitors, making them FACTS devices. Another FACTS of 90" means that the capacitor is fully inserted in the circuit,
devices developed for series compensation is the SSSC (Static that is, the fundamental impedance is 1 p.u and the switches
Synchronous Series Compensator) which is based on voltage are turned off completely. On the other hand, if the blocking
source converters .[2]. This device presents high flexibility angle is 180",the switches are on full conduction, bypassing
level but has a much higher cost involved due to the complex- the capacitor, meaning a zero impedance. So, a continuous
ity of the converters.
variation of the equivalent series capacitance of the GCSC is
This paper presents the GCSC, its main components, prin- achievable in the range of 90" < y < 180".
ciple of operation, typical waveforms and main applications.
Referring again to Fig. 2, one can see that the voltage
An important issue discussed in this paper is the duality of the waveform in the capacitor is non-sinusoidal. Fig. 4 shows the
GCSC with the well-known TCR,largely used in static com- main harmonic components of the voltage waveforms as a
pensation. Some rating comparisons with the TCSC are pre- function of the blocking angle y. The voltages are in per-unit
sented, showing that the GCSC may have several advantages values of the capacitor maximum voltage. As the voltage in
over the TCSC. Technological problems and possible trends the GCSC is lower than the system voltage, depending on the
relating to the development of high-voltage and high-current compensation level, the harmonics will be proportionally
self-commutated valves ate also discussed. Results of ATP lower, in percent values, when converted to the system basis.
digital simulations are presented, showing time-responses of
the GCSC and proving its effectiveness in controlling power B. Prospective Applications
ffow through a meshed transmission system.
The GCSC could be typically used in applications where a
TCSC is used today, mainly in the control of power flow and
11.
GATECONTROLLED SERIES CAPACITOR
damping of power oscillations. The GCSC may operate with
an open Ioop configuration, where it would simply control its
A. Principle of Operalion
reactance, or in closed loop, controlling power flow or current
From Fig. 1, one can see that if the self-cornmutated in the line, or maintaining a constant compensation voltage
switches turn off, the capacitor is inserted in the circuit, com- [2]. Power Oscillation Damping schemes may also be easily
pensating the line inductance. When the switches are turned
Hannonlcs In like GCSC
0.2,
I
on, the capacitor is bypassed, canceling the compensation effect. The switches start to conduct only when their anodecathode voltage tends to become positive, exactly when the
ow
capacitor voltage vc is zero. The line current i of the controlled power line flows altemately through the switches and
U1
the series capacitor.
The level of series compensation is given by the funda4 2
90 100 110 120 130 140 150 160 170 180
mental component of the capacitor voltage VC. This level may
Y (&grreS)
be varied by controlling the blocking angle y of the semicon-
,
Fig.4 - Harmonic voltages in the GCSC as a function of the blocking angle y.
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3
attainable with the GCSC.
The typical configuration of the GCSC would be a system
composed of smaller devices connected in series, in a socalled multi-module configuration. In this configuration, the
semiconductor valves have lower voltages and voltage harmonic distortions are kept low.
The comparison between a GCSC and a TCSC will favor
the fmt equipment in most situations where controllable series
compensation is needed (see Section III). As research on the
GCSC is still under way, it is possible that a break-even MVA
rating is found, above which the TCSC will be more advantageous due to possible valves and protection requirements of
the GCSC. The authors foreseen that the GCSC should also be
a very interesting alternative for retrofitting fixed series capacitor installations, making them FACTS devices.
HI. DUALITY wml TZIE THYRISTOR CONTROLLED
REACTOR
One interesting feature of the GCSC is that its operation is
exactly the dual of the well-known thyristor Controlled reactor
( E R ) [2][3], used for shunt compensation, usually with a
fKed capacitor in parallel. In fact, one may easily observe that
the voltage waveform o f the GCSC shown in Fig. 2 is similar
to current waveforms of the TCR (e.g., see [2] and [3]). Table
1 shows a comparison between the dual characteristics of both
equipment. The duality can easily be extended to the valves
[7],making it easier to understand the requisites of a GCSC
valve. Considering that the TCR is the dual of the GCSC and
that the former is a longtime adopted solution for controlled
shunt compensation, one may conclude that the GCSC is the
natural solution for controlled series compensation.
TABLE1 -DUAL
CHARACTERlSTlCS OF THE GCSC AND THE TCR
Gate Controlled Series Capacitor
Semiconductor switches in
parallel witb a capacitor
L Series connected to transmission lines
ISupplied by a current source
ISwitches control amount of
current in the caDacitor
e Voltage controlled by switches'
blocking angle
ISwitches 6re and block with
zero voltage
D
I
Thyristor CothUed Reactor
in
S&condu&
switches
series with a reactor
Shunt connected to transmission lines
Supplied by a voltage source
Switches control amount of
voltage in the reactor
Current controlledby switches'
m g ansle
Switches fire and block witb
zero current
/I-
II
+
-2
ctmn
183
~ringalgleNdeim=)
Fig. 5- Typical impedance characteristicof the TCSC.
function of the firing angle a. The region where operation is
allowed is shaded. The resonance is also shown in this figure.
, ,Z and Z, are the maximum and minimum values of the
impedance of the TCSC operating in the capacitive region.
Z, corresponds to the capacitive reactance oniy, that is, at
this point the thyristors do not conduct and the reactor is not
present. , Z
,
corresponds to the value of equivalent impedance of the capacitor and the thyristor controlled reactor for
the minimum fuing angle ami,,.
This angle is limited in order
to avoid the potentially dangerous operation near the parallel
resonance region.
For the GCSC, the minimum reactance is equal to zero.
The maximum reactance, which corresponds to the capacitor
reactance, should be equal to Zmx of the TCSC to obtain the
same maximum compensation level. The relationship between
capacitances of both devices is the following:
CCLX
- 2"
CTCX
zm,
(1)
Moreover, the same steady-state voltage is applied to both
the TCSC and GCSC capacitors. As for the current, it is always higher in the TCSC than in the GCSC [XI, as the parallel-connected TCR needs to boost the capacitor current in order to increase the capacitor voltage.
Besides needing a larger capacitor, the TCSC will also
need a reactor that should be rated for the same current of the
valve. As a general conclusion, the GCSC needs less passive
components, as its capacitor is much smaller, with lower current rating, and it does not need any reactor at all.
The valve currents in the TCSC are always higher for devices where the relation between the maximum and minimum
impedance is greater than 2, what happens in most of the existent installations throughout the world [2][8]. On the other
hand, the GCSC valves should be rated for a voltage slightly
higher [XI.
B. Example ofcomparison the BruziIiun North-South Interconnection
~
A. Main Components
A simple comparison of rating of the GCSC and the widely
adopted TCSC is presented here. For this analysis, although
the TCSC may be designed to operate in the inductive region,
it is assumed that it normally operates only in the capacitive
region. Also, it is considered that the maximum compensation
capacity is equal for both devices: they should have the same
maximum capacitive impedance when compensating at their
maximum.
Fig. 5 shows a typical impedance curve for a TCSC, as a
To illustrate the previous conclusions, a GCSC was rated to
prospectively substitute one of the TCSC already installed in
the Brazilian North-South Interconnection [SI. This transmission line needs a series controller to damp out a low frequency
power oscillation between Brazilian North and South grids.
The existent TCSC has a reactive power rating of I D S Mvar
and is installed in a 550 kV transmission line with a rated CUTrent of 1500 A. This equipment normally operates with a capacitive reactance of 15.92 0, when there is no need of
L
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4
-
Fig. 6 GCSC connected to a current source
17KlD1
,
15WO
06
08
I
,
,
,
1.2
14
16
I
ia
damping power swings.
time ( 5 )
For rating purposes, it was assumed that the GCSC should Pig.8 - Open loop responses of the GCSC and TCSC with low levels of comhave the same maximum reactance and nominal Mvar of the
pensation, varying f"35% to 45% at 800 ms, and back to 35% at 1.3s
TCSC. Also, it was assumed that the GCSC operates at the
same continuous effective reactance of the TCSC. It should be
v. RE-SULTSOF DIGITAL fhdlLATIONS
pointed out that, although both devices have the same function
in the power system, they are quite different. For this reason, A. Time Responses
other designing strategies are possible for the GCSC, but it is
The GCSC can rapidly vary its reactance, whenever its
beyond the scope of this paper to find an optimal designing blocking angle signal is varied. To demonstrate that, a simple
strategy. Table 2 Summarizes the basic characteristics of the system was modeled in the ATP simulation package, consistexisting TCSC and a GCSC proposed to substitute it.
ing of a GCSC fed by a current source, as shown in Fig. 6.
TABLE 2 -EXISTENT TcsC A N D PROFQSED wsc RATINGS FOR %AZIUAN
The GCSC has a maximum reactance of 26.5 R. Initially, the
NORTH-SOUTH INTERCONNECTION
self-commutated switches are operating with a blocking angle
Parameter
TCSC
I
ccsc
j of 120". At Zooms, the compensation level is decreased by
Capacitor Reactance
13.27 i2
39.81R
increasing the blocking angle to 150'. Then, at Moms, the
Capacitance
200 p
66.6 pF
compensation level is returned to the initial value. The result
Max. Reactance
39.81 Q
39.81Q
of the simulation is shown in Fig. 7.
Dynamic Control Range
13.27- 39.81 Cl
0 - 39.81 R
The topology shown in Fig. 6, although very simple, is in59.7 kV
59.7kV
Max. Fundamental Voltage
teresting to analyze the dynamic behavior of the equipment, as
60.3 kV
59.7kV
Max. RMS Voltage
the only other element in the network is an ideal current
5025 A
1500 A
Max. RMS Capacitor Current
source. The same topology is used in the ATP to test both the
Max. Reactor Current (rms)
3735 A
no reactor
GCSC and TCSC of Table 2. The current source now has an
Max. Valve Current (rms)
3735 A
1500 A
rms magnitude of 1500 A. In the fust simulation, each equipMm.Voltage of the Valves
51.34I
59.73/
ment is compensating at low level (35% of X-). Next, the
(rindpeak)
74.41kV
84.47 kV
compensation increases to 45% and decreases again to 35%.
Fig. 8 shows the fundamental voltage response of each
equipment to this input. Both equipment have similar open
loop responses at this level of compensation.
Another simulation was performed, with higher levels of
1.5
(kv)
1
0.5
=z
0
4.5
-1
%?ow
40000
-1.5 0
Fig.7
0.1
E
-
)-I200
0.2
0.3
Time ( 5 )
I.
FI 50'
t
0.4
[
FI20'
r
Time response of a GCSC connected to a current source
06
08
1
12
tune (SI
14
16
IB
Fig 9 - Open loop responses of the GCSC and TCSC w~thhgh levefs of
compensation, varymg from 80% to 90% at BOO ms,and back to 80% at 13 s
I
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5
'
Fig, 10 -Equivalent 500 kV and 765 LV Sy&m of the South of Brazil.
series compensation. Now the blocking angle is varied fiom
80% to 90% and back to 80%, in a pattern similar to that of
the previous simulation. The results are in Fig. 9. It is clear
that the TCSC is much slower than the GCSC at high levels of
compensation, i. e., with high currents af capacitor and reactor. On the other hand, the open loop response of the GCSC
does not differ too much from that shown in Fig. 8, with low
level of series compensation.
B. Power Flow Scheduling in a Meshed Network
Zn order to show the capability of the GCSC to control
power flows, an ATP simulation of a meshed transmission
system was performed. The system, shown in Fig. 10, is an
equivalent of part of the 500 kV and 750 kV South-Southeast
Brazilian Network. Transmission lines 1 and 2, both in
500 kV, form a loop-flow: PI in Line 1 is 50% higher than the
P2 in Line 2. A GCSC, capable of compensate up to 80% of
series reactance, is operating with about half of its capacity.
The GCSC increases its compensation to the maximum,
thus boosting the power flow through line 2 and establishing
the balance between the usage of both lines. Fig. 11 shows the
2000
I
power flows in both lines before and &er the increment of
compensation by the GCSC. It i s clear that the device could
quickly establish power flow equilibrium between both lines.
This test shows, in fact, that the GCSC can be used to control
power flow at different levels, which can be chosen by the
system operator. Fig. 12 shows the voltage in the GCSC before and after the step in the compensation of Line 2.
VI. HIGH POWER SELF-COMMLJTATED VALVES: SOME
,"OLOGlCAL
T"Ds
The design of a reliable high power self-commutated
switch is of paramount importance for the development and
manufacturing of a GCSC for an EHV transmission line. A
typical GCSC would he a multi-module equipment. Each
module might be designed to be a small GCSC cell, comprising a relatively low voltage switch valve or even a single pair
of high power switches. Several GCSC cells could be connected in series to form larger multi-module GCSC. The selfcommutated switch could be the GTO or, most likely, a more
modern semiconductor device, like the IGCT. The switch has
to be of the symmetrical type, in order to block reverse volt-
I
j
.
.
..
l_._._.l_l_-..
I
F1400
E
50
5 l2O0
::I
g 1000
,
-
g o
;
-50
400
03
04
05
06
07
time 6)
Fig I 1 - Power flows through Lines I and 2. after campensailon of Line 2
increases from 43%to 80% of the senes reactance
d
1
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6
ages.
[4] A. A. Edris, Tower Electronic-Based T&D Controllers At Technological Crossroad", EPRI Journal O n h e , August 2002 at
Even with small GCSC cells, it may be necessary to conhttp://www.epri.con~~~~~.~p?d~~ea~&id~63.
nect a number of semiconductor switches in series. The series [5] G. G. Karady, T. H. Orbmyer. B. R F'ilvelait, D. Maratukulam, "Continuously Regulated Series Capacitor," IEEE Trnns. Power Delrvery,
connection of GTO in hard-commutated converters to form
vol. 8, no.3, July 1993, pp. 1348-1354.
high power adjustable speed drive systems (ASD) has been a
L. F. W.de S o w E.H. Watanabe, M Aredcs, %TO Controlled Series
technical challenge for years. This is not the case of the [6] Capacitors: Multi-modde and Multi-pulse Arrangements,"IEEE Tram.
Power Delivery, vol. 15, no. 2. April 2000. pp. 725-731.
GCSC, as it is a zero voltage switching equipment, what
makes the series connection of self-commutated switches {TJ L.F. W.de S o w E.H. Waianabe, M Aredcs. "A GTO Controlled
Series Capacitor for Distribution Lines," Proceedings of CIG& 1998
much easier [9]. Care must be taken with stray inductances
Session, Session 14, paper 201, Paris,August 1998.
due to leads and cables that should be considered in the proj- [8] L. F. W.de So- E. H. Watanabe, I. E. R. Alves, L. A. S. Pilotto.
'Thyristor and Gate Controlled Series Capaci-tors:Comparison of Comect of snubber circuits. Another important issue to consider is
ponents Rating", Proceedings of IEEE PES General Meeting, Toronto,
the Wdt limit of the semiconductor switches [lo].
July 2003.
VII. CONCLUSIONS
This paper presented a novel equipment for controllable series compensation of transmission lines: Gate Controlled Series Capacitor (GCSC). Some of the basic concepts behind the
equipment were reviewed. Emphasis was given to the fact that
the GCSC is the dual device of the Thyristor Controlled Reactor (TCR). This special characteristic not only helps to understand the GCSC principle of operation, but also makes the
analysis and possibly the equipment design rather easier. Due
to this duality, the authors believe that the GCSC may be a
more natural solution for series compensation than the TCSC,
and may be as widely adopted for series compensation as the
TCR is for shunt Compensation.
Comparison with the TCSC has shown that the GCSC is
more compact, with lesser passive components: it does not
need reactors and its capacitor bank is much smaller. Also, the
switches and capacitor currents are smaller in the GCSC. Besides that, the semiconductor of the GCSC should be rated to a
slightly higher voltage than the SCR valves of the TCSC.
Some important issues regarding the development of highpower valves are discussed. The main focus is the need of
development of a high-power valve comprising series connected self-commutated switches capable of blocking reverse
voltage. Attention should also be given to the rate of rise of
current in the valves.
Simulation results demonstrate the operating principles of
the GCSC. Its open-loop dynamical response is faster than
that of the TCSC, specially at higher compensation levels.
Also, an example proved the capability of the GCSC to control power flow in transmission lines.
As a final remark, the authors believe that this new device
may be an excellent solution for transmission line controlled
series compensation. In the near future, the authors expect to
prove this technology by developing a full-scale GCSC prototype to operate in an HV transmission system.
VIII. R E " C E . 3
E. W.Kimbark "Improvementof System Stability by Switched Series
Capacitor,"JEW Trans. Power Apparatus undSystems, vol. 85, Febmary 1966,pp. 180-188.
[2] N. m o r a n i , L. Gyugyi Understanding FACIS: Concept.? and Techn d o ofFlexible
~
AC Trmsmmton SysIrms. EEE Press,2000.
[31 T.J.E.Miller, Rractrve Power Control in Ekcfric Systems. New York
Wiley, 1982.
[I]
o
w M D. BelIar, "Series
191 E. H.Wafanabe. M Aredes, L.P. W.de S
C o d o n of Power Switches for Very High Power Appkications and
Zero Voltage Switching." IEEE Trans. Power Elecironics, voL 15. no. 1,
January 2000, pp. 44-50.
[IO] M U N e j 4 T.H. Ortmeyer, "GTO TZlyristor Controlled Series Capacitor Switch Performance,"IEEE Trnns. Power Delivery, vol. 13, no. 2,
April 1998. pp. 615-621.
E.BIOGRAPHIES
Edson EIimkam Wntannbe (M'76, SM'02) was born in Rio dc Janeiro State,
Brazil, on November 07, 1952. He received the B.Sc. in Electronic Engineering and MSc. in Electrical Engineering in 1975 and 1976, respectively, h m
the Federal University of Rio de Janeiro. In 1981 he got the D.Eng. degree
&om Tokyo Institute of Tecbnology,Japan. In 1981 he became an Associate
Professor and in 1993 a Professor at COPPEiFederal University of Rio de
Janeiro. where he teaches Power Eleclronics. His main fields of interests arc
converters analysis, mcdeling and desim active filters and FACTS technologies.Dr. Watanabe is a member of the IEEJapan, The Brazilian Society for
Automatic Controland The Brazilian Power Elecbnics Society.
Luiz Felipe W ~ W de
I Son= (S'94, A'98, M W )was bom in Niterbi, Rio
de Janeiro State. B d . on Januaty IO. 1972. He received the B.Sc. degree
from Flumineme Federal University, Rio de Janeiro State, in 1994 a d the
U&.degree in Electrical Engineering from Federal University of Rio de
Janeiro in 1998. He is cwenlly w o r m towards his doctorate degree at Federal University of Rio de Janeiro. From 1994 to 1996 he worked at Fumas
Centrais Eltirifas W A as a hydro power plant maintenance engineer. Since
1996 he works at CEPEL as a research engineer. His main fields o f interests
are power quality and FACTS.
Fhbio Domingues de Jesw was bom in Bnrretos, S b Paul0 State, B m l , on
M a y 12, 1971. He reoeived the E. S. degree in Electrical Engineering fiom
Federal Institutionof High Education of SHO Jo%Odel Rei, Brazil in 2000 and
the U S c . degree at Elecbical Engineering Deprbmni in Federal University
of Juiz de Fora, Brazil in 2002. He is pursing his D.Sc.degree at Electrical
Engineering Department from COPPE Federal University of Rio de Jnneim,
B m i l His present research interests include the high-power electronics, m d y sis and mni~olin FACTS.
JX.k Alvm Jr. (M'92F was h m in Juiz de Fora, B d , on November 30,
1963. He received the B.Sc., M.Sc. and D.Sc.degrees in electrical engineering, in 1986,1991 and 1999, respectivety. fiom the Federal University of Rio
de Janeiro. Since.1995 he has been w
o
r
m at CEPEL, the Brazilian Eleclrical
Energy Research Center. He is currently Projwt Manager. Dr.Aives' research
interests are in the analysis of HVdc "ission
systems, FACTS devices,
Power Electronic controllers, Distribution Systems and Metering. He became
a Member of the Institute of Electrical and Elecbnics Engineers (EEE) in
1992. He is currently a Member of the IEEE Power Engineering Society and
-
Sectetary of IEEERio de Janeiro Section.
A n d d Bmnm "99)
was born in Nova Igmqy Rio de Janeiro, Brazil, on
Junc 27, 1967. He received ttte B.Sc. and M.Sc. degrees in electrical enpineering, in 1990 and 1994, respectively fiom the Gama Filho University and
from the Catholic University of Rio de Janeiro. From 1990 to 2003 he was
with =EL,
initially as a graduafd student and then as a research engineer
with inkrest in the transienddynamic analysis of power systems includmg
HVdc transmission and FACTS devices.In 2004, Mr.Bianco joined Andrade
& Canellas Consulting, where he is the head of the elechical and energetic
studies group.
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