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This article was downloaded by: [Indian Institute of Technology - Delhi]On: 30 November 2012, At: 03:18Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House37-41 Mortimer Street, London W1T 3JH, UK
Electric Power Components and SystemsPubl icat i on detai ls, including inst ruct ions for authors and subscr ipt ion inform ation:h t t p : / / w w w . t an df o nl i ne . co m / l oi / u em p 20
React ive Power Cont rol of Autonomous Wind-DieselHybr id Power Systems Using Simul inkR. C. Bansal
a& T. S. Bhatti
b
aElect rical and Elect ronics Engineering Division, School of Engineering and Physics, The
Universi t y of t he South Paci f ic, Suva, Fi j ib
Centre for Energy Studies, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi,
IndiaVersion of r ecord f irst p ubli shed: 19 Sep 2007.
To cite this art icle: R. C. Bansal & T. S. Bhat t i (2007): React ive Power Cont rol of Autonom ous Wind-Diesel Hybri d PowerSyst ems Using Sim ulink , Elect ric Power Component s and Syst ems, 35:12, 1345-1366
To link to t his art icle: ht t p : / / dx.do i .o rg/ 10.1080/ 15325000701426096
PLEASE SCROLL DOWN FOR ARTICLE
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http://dx.doi.org/10.1080/15325000701426096http://www.tandfonline.com/page/terms-and-conditionshttp://dx.doi.org/10.1080/15325000701426096http://www.tandfonline.com/loi/uemp20 -
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Electric Power Componen ts an d S ystems, 35:13451366, 2007
Copyright Taylor & Francis Group, LLC
ISSN: 1532-5008 print/1532-5016 online
DOI: 10.1080/15325000701426096
Reactive Power Control of AutonomousWind-Diesel Hybrid Power Systems Using Simulink
R. C. BANSAL
Electrical and Electronics Engineering Division
School of Engineering and Physics
The University of the South Pacific
Suva, Fiji
T. S. BHATTI
Centre for Energy Studies
Indian Institute of Technology, Delhi
Hauz Khas, New Delhi, India
Abstract This article presents reactive power control of autonomous wind-dieselhybrid power system for realistic load disturbance using Simulink. The simulationblock diagram of wind-diesel, multi-wind-diesel, and wind-multi-diesel hybrid systembased on Simulink is developed. Reactive power control performance is comparedusing three different types of static VAR compensator (SVC) models. Reactive power
performance is also compared for wind-diesel, multi-wind-diesel, and wind-multi-diesel hybrid power systems.
Keywords autonomous wind-diesel hybrid power system, diesel generator set, in-
duction generator, multi-wind-diesel, reactive power compensation, Simulink, staticvar compensator, wind-multi-diesel
1. Introduction
In recent years there has been continuous growth of power generation from non-conven-
tional energy sources. The main advantages of non-conventional sources of power gener-
ation are no fuel consumption in most cases, sustainable, and eco-friendly. The major dis-
advantage with these energy sources is that they are generally intermittent or fluctuating in
nature.
The non-conventional sources such as wind and micro/mini hydro, etc. are generally
integrated with diesel system to increase the reliability of the system to supply power to
the isolated loads. Such systems are called isolated/autonomous hybrid power systems.
In hybrid power systems, there may be more than one type of electrical generators [1,2]. In such circumstances it is normal, though not essential, for generator(s), usually on
Received 28 September 2006; accepted 13 March 2007.Address correspondence to Prof. R. Bansal, Electrical and Electronics Engineering Divi-
sion, School of Engineering and Physics, Laucala Campus, Private Mail Bag, Suva, Fiji. E-mail:[email protected]
1345
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1346 R. Bansal and T. Bhatti
Nomenclature
A, B , C system, control, and disturbance matrix, respectively
, thyristor firing angle and small deviation in thyristor firing angle,
respectively
power angle between terminal voltage and armature internal emf
BSVC, BSVC reactive susceptance of the SVC and small change in its value,
respectively
EM, EM electromagnetic energy stored in induction generator (IG) and
small deviation in energy stored, respectively
Efd 1, Eq1, E0
q1,
Efd 2 , Eq2, E0
q2
small change in voltages of exciter, internal armature emf under
steady state and transient conditions of synchronous generator
(SG) 1 and 2 respectively
KA, KE , KF, KR,
K , KV
amplifier, exciter, stabilizer, VAR regulator, thyristor firing, and
hybrid power system gain constants, respectively
KP, KI proportional and integral controller gain constants of the VAR
regulator, respectively
IG
efficiency of the IG
PI W, PIG , PS G real power input to the IG, real power generated by IG and SG,
respectively
PL, QL real and reactive power load demand, respectively
QI G, QI G 1, QI G 2 reactive power required by IG, IG 1, and IG 2, respectively
QS G, QS G 1, QS G 2 reactive power generated by SG, SG 1, and SG 2, respectively
QSVC reactive power generated by SVC
Qc rating of the SVC
QR system reactive power rating
r1, x1, r0
2, x0
2 stator resistance, stator reactance, rotor resistance and rotor re-
actance referred to primary side of IG, respectively
Req , Xeq , Xm equivalent resistance, equivalent reactance and magnetizing re-
actance of the IG, respectively
s slip of the IG
Td SVC average dead time of zero crossing in a three phase systemT thyristor firing delay time
T1, T2, T3, T4 time constants of the SVC regulator of lead-lag type
TE , TF, TR, TV exciter, stabilizer, regulator, and hybrid power system time con-
stants, respectively
T0do
direct axis open circuit transient time constant
V system terminal voltage
V, Vref small change in terminal and reference voltage, respectively
Va1, Va2,
Vf 1, Vf 2
small change in the amplifier output of amplified 1 and 2, and
exciter feedback voltages of exciter 1 and 2, respectively
xd, x0
ddirect axis reactance of SG under steady state and transient state
conditions, respectively
x, u, p state, control, and disturbance vector, respectively
the diesel, to be synchronous, and wind turbine generator(s) to be asynchronous (induc-
tion) [2]. An IG offers many advantages over a conventional SG, like reduced unit cost,
ruggedness, brushless (in squirrel cage construction), absence of separate DC source, ease
of maintenance, self-protection against severe overloads and short circuits, etc. [36]. A
major disadvantage of an IG is that it requires reactive power support for its operation.
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Reactive Power Control of Hybrid Power Systems 1347
In addition, most of the loads are also inductive in nature. The mismatch in generation
and consumption of reactive power can cause a serious problem of large voltage fluctu-
ations at generator terminals. A number of FACTS (flexible AC transmission systems)
devices have been developed to provide the reactive power to the system. SVC is one of
the FACTS device that has been used in conventional power systems, and can also beemployed in isolated power systems.
In recent times, there has been large number of application of Matlab/Simulink
developed by the Math Works Inc., for solving various power system problems [710].
With the addition of several toolboxes and Simulink, Matlab provides an interactive
environment with hundreds of reliable and accurate built in functions. Simulink is a
window-based package built in the Matlab software and consists of a library of basic
building blocks, which can be combined to form a dynamic model.
This article presents reactive power control of autonomous wind-diesel hybrid power
system for realistic (step plus stochastic) load disturbance using Simulink. In the con-
sidered wind-diesel hybrid system (transfer function block diagram shown in Figure 1),
SG along with an IEEE type-I excitation system is considered to be connected to diesel
generator (DG) set and IG on wind system. The DG set acts as a local grid for the
wind energy conversion system. The system has a SVC to provide the required reactive
power in addition to the reactive power generated by the SG. Simulink block diagrams
for autonomous wind-diesel, multi-wind-diesel (2 wind-1 diesel), and wind-multi-diesel
(1 wind-2 diesel) hybrid power systems have been developed as shown in Figures 2, 3,
and 4, respectively, to compare their reactive power requirement performance. Figures 3
and 4 can be developed by incorporating the components of multiplicity of wind and
diesel system, respectively.
Simulation block diagrams of three different types of SVC models have been used to
compare their performances. The basic difference in the transfer function block diagrams
is the type of VAR regulator used. In SVC type-I [11, 12] the VAR regulator is an
amplifier with a gain and time constant. The regulator in SVC type-II [13, 14] is a twin
lead-lag type for providing compensation for the time delays in the firing circuit and due
to phase sequence dead time delay of zero crossing. The VAR regulator is proportionalplus integral in SVC type-III [15, 16]. The Simulink block diagrams of IEEE type-I
excitation system and SVC type-I, -II, and -III have been shown in Figure 5(a), 5(b),
5(c), and 5(d), respectively. The advantage of simulation block diagram is that a block
diagram containing many elements can be replaced by a single block having input and
output terminals, e.g., SVC and excitation system in Figures 24 have been shown by
single block.
2. Mathematical Modeling of Wind-Diesel Hybrid System
Detailed mathematical modeling of autonomous wind-diesel hybrid power system based
on power equations has been presented in [1719]. System data considered are given
in Appendix 1. Small changes in real power are mainly dependent upon the frequency,
whereas small change in reactive power is mainly dependent on voltage [20]. The ex-citation time constant is much smaller than the prime mover time constant, its transient
decay much faster, and does not affect the load frequency control (LFC) dynamic. Thus,
cross coupling between LFC and AVR loop is negligible. The reactive power balance
equation of the system under steady state condition is
QS G C QSVC D QL C QI G (1)
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1348 R. Bansal and T. Bhatti
Figure 1. Transfer-function block diagram for reactive power control of wind-diesel autonomoushybrid power system.
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Reactive Power Control of Hybrid Power Systems 1349
Figure 2. Simulation block diagram of wind-diesel autonomous hybrid power system for step plus
stochastic disturbance.
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1350 R. Bansal and T. Bhatti
Figure 3. Simulation block diagram of multi-wind-diesel autonomous hybrid power system for
step plus stochastic disturbance.
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Reactive Power Control of Hybrid Power Systems 1351
Figure 4. Simulation block diagram of wind-multi-diesel autonomous hybrid power system for
step plus stochastic disturbance.
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1352 R. Bansal and T. Bhatti
Figure 5. Simulation block diagram of (a) IEEE type-I exciter, (b) SVC type-I, (c) SVC type-II,
and (d) SVC type-III.
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Reactive Power Control of Hybrid Power Systems 1353
For the small incremental reactive power balance analysis of the hybrid system, (1) in
Laplace form can be written as
V.s/ D fKV=.1 C sTV/gfQS G .s/ C QSVC.s/ QL.s/ QI G .s/g (2)
KV D1
DV(3)
TV D2HR
DVV0(4)
where V0 is the nominal value of system voltage, HR is a constant of the system and its
unit is s and its value depends upon the constant Kr (considering that system reactive
power rating is Kr times the rated magnetizing reactive power of the IG), DV is the small
increase in reactive power loads with small increase voltage, i.e., DV D @QL=@V p.u.
kVAR/p.u. kV. The parameter DV can be found empirically. KV =.1 C sTV/ is transfer
function of hybrid power system. The values of KV and TV can be computed using
(3) and (4), respectively, with the data given in Appendix 1, and their values have been
shown in Figures 2, 3, and 4. The values of KV and TV remain the same with SVC
type-I, type-II, and type-III for wind-diesel hybrid power system. The following section
presents the mathematical modeling of various components of hybrid systems.
2.1. The Flux Linkage Equations
The flux linkage equation of the round rotor synchronous machine for small perturbation
is [21]
d
dtE0q D
Efd Eq
T0do
(5)
In (5), Eq is given by
Eq Dxd
x0d
E0q .xd x
0
d/
x0d
cos V (6)
For small changes (5), using (6) in Laplace transform form can be written as
.1 C sTG/E0
q .s/ D K1Efd .s/ C K2V.s/ (7)
where
TG Dx0
dT0
do
xd(8)
K1 D x0d=xd (9)
K2 D f.xd x0d/ cos g=xd (10)
The values of K1 (K11 and K12 in case of wind-multi-diesel system) and K2 (K21
and K22 in case of wind-multi-diesel system) can be computed using (9) and (10),
respectively, with the data given in Appendix 1, and their values have been shown in
Figures 2, 3, and 4. The values of K1 and K2 remain the same with SVC type-I, type-II,
and type-III for wind-diesel hybrid power system.
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1354 R. Bansal and T. Bhatti
2.2. The Synchronous Generator Equations
Under transient condition QSG is given by [20]
QS G D E0
qV cos V2
x0d
(11)
For small perturbation (11) can be written as
QS G DV cos
x0d
E0q CE 0q cos 2V
x0d
V (12)
In Laplace transform (12) can be written as
QS G .s/ D K3E0
q.s/ C K4V.s/ (13)
where
K3 D .V cos /=X0d (14)
and
K4 D .E0q cos 2V /=x0
d (15)
The values of K3 (K31 and K32 in wind-multi-diesel system) and K4 (K41 and
K42 in wind-multi-diesel system) can be computed using (14) and (15), respectively,
with the data given in Appendix 1, and their values have been shown in Figures 2, 3,
and 4. The values of K3 and K4 remain the same with SVC type-I, type-II, and type-III
for wind-diesel hybrid power system.
2.3. IEEE Type-1 Excitation System Equations
IEEE type-1 excitation system [22], as shown in Figure 5(a), is considered for the syn-
chronous generator of the hybrid system. From the block diagram, the transfer function
equations neglecting saturation function (SF) can be written as
Efd.s/ D1
KE C sTEVa.s/ (16)
Va.s/ DKA
1 C sTA V.s/
KF
TFEfd .s/ C Vref.s/
(17)
Vf .s/ DKF=TF
1 C sTFEfd.s/ (18)
The values of transfer functions of amplifier, exciter, and stabilizing circuit, as shown
in Figure 5(a), are obtained using the data of Appendix 1. This excitation system has
been represented by a single block in Figures 24.
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Reactive Power Control of Hybrid Power Systems 1355
2.4. The Induction Generator Equations
The small deviation in reactive power absorbed by the IG by neglecting the effect of
variation in reactive power with the variation of slip/speed (constant slip/speed model)
and by considering the effect of variation in reactive power with variation in slip/speed(variable slip/speed model) can be written as [1719]
QIG .s/ D K5V.s/ (19)
where
K5 D2V Xeq
R2Y C X2eq
(20)
QIG .s/ D K6PI W.s/ C K7V.s/ (21)
where
K6 C
Xeq
RP .R2Y C X2eq /=2RY (22)
K7 D2V
R2Y
C X2eq
"Xeq
RPXeq
fRP .R2Y
C X2eq/=2RYg
#(23)
where
RP Dr 02s
.1 s/ (24)
RY D RP Req (25)
Req D r1 C r0
2 (26)
Xeq D x1 C x0
2 (27)
This article considers the variable slip model of IG. The values of K6 (K61 and K62
in multi-wind-diesel system) and K7 (K71 and K72 in multi-wind-diesel system) can
be computed using (22) and (23), respectively, with the data given in Appendix 1, and
their values have been shown in Figures 2, 3, and 4. The values of K6 and K7 remainthe same with SVC type-I, type-II, and type-III for wind-diesel hybrid power system.
2.5. SVC Equations
The reactive power supplied by the SVC is given by [23]
QSVC D V2BSVC (28)
For small perturbation, (28) can be written in Laplace transform form as
QSVC.s/ D K8V.s/ C K9BSVC.s/ (29)
where
K8 D 2VBSVC (30)
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1356 R. Bansal and T. Bhatti
and
K9 D V2 (31)
The state equations of a SVC type-I in Laplace transform can be written as
BSVC.s/ D1
1 C sTdB0SVC.s/ (32)
B0SVC.s/ DK
1 C sT.s/ (33)
.s/ DKR
1 C sTR.Vref.s/ V.s// (34)
The state equations of a SVC type-II in Laplace transform can be written as
01.s/ D1 T2=T4
1 C sT4
0.s/ (35)
02.s/ DKR.1 T1=T3/
1 C sT3.Vref.s/ V.s// (36)
where
0.s/ D 02.s/ C KRT1
T3.Vref.s/ V.s// (37)
.s/ D 01.s/ CT2
T4.0.s// (38)
The state equations of a SVC type-III in Laplace transform can be written as
0.s/ D KIs
fVref.s/ V.s/g (39)
where
.s/ D 0.s/ C KPfVref.s/ V.s/g (40)
Equations (32) and (33) remain the same in SVC type-II and type-III.
The values of K8 and K9 can be computed using (30) and (31), respectively, with
the data given in Appendix 1, and their values have been shown in Figures 24. The
values of K8 and K9 remain the same with SVC type-I, type-II, and type-III for wind-
diesel hybrid power system. VAR gain KR in SVC type-I and type-II; and KP and KIin SVC type-III have been optimized and their values have been shown in Figures 5(b),
5(c), and 5(d), respectively. Dynamic responses of hybrid system have been shown in
Figures 610 using optimum settings of the gain parameters of the SVC.Based on the above mathematical equations, Simulink block diagram of wind-diesel,
2 wind-1 diesel, 1 wind-2 diesel isolated hybrid power system have been developed as
shown in Figures 2, 3, and 4, respectively. The state space equations can be written in a
standard form for load voltage control system as
Px D Ax C Bu C Cp (41)
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Reactive Power Control of Hybrid Power Systems 1357
Figure 6. Dynamic responses of the wind-diesel autonomous hybrid power system with SVC
type-I for 1% realistic increase in reactive power load plus 1% step increase in input wind power.
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1358 R. Bansal and T. Bhatti
Figure 7. Dynamic responses of the wind-diesel autonomous hybrid power system with SVC
type-II for 1% realistic increase in reactive power load plus 1% step increase in input wind power.
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1360 R. Bansal and T. Bhatti
Figure 9. Dynamic responses of the multi-wind-diesel autonomous hybrid power system with SVC
type-II for 1% realistic increase in reactive power load plus 1% step increase in input wind power
of both wind machines.
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Reactive Power Control of Hybrid Power Systems 1361
Figure 10. Dynamic responses of the wind-multi-diesel autonomous hybrid power system with
SVC type-II for 1% realistic increase in reactive power load plus 1% step increase in input wind
power.
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1362 R. Bansal and T. Bhatti
For the autonomous wind-diesel system with SVC type-I, II, and III, 2 wind-1 diesel
with SVC type-II, and 1 wind-2 diesel with SVC type-II hybrid power system state space
equations can be written as
2.6. Wind-diesel System
State space equations with SVC type-I
Px D Efd Va Vf E0
q BSVC B0
SVC V T
u D Vref
p D QL PI WT (42)
State space equations with SVC type-II
Px D Efd Va Vf E0
q BSVC B0
SVC 0
1 0
2 V T
u D Vref
p D QL PI WT (43)
State space equations with SVC type-III
Px D Efd Va Vf E0
q BSVC B0
SVC 0 V T
u D Vref
p D QL PI WT (44)
2 Wind-1 diesel system with SVC type-II
Px D Efd Va Vf E0
q BSVC B0
SVC 0
1 0
2 V T
u D Vref
p D QL PI W 1 PI W 2T (45)
1 Wind-2 diesel system with SVC type-II
Px D Efd 1 Va1 Vf 1 E0
q1 Efd 2 Va2 Vf 2 E0
q2
BSVC B0
SVC 0
1 0
2 V T
u D Vref
p D QL PI W T (46)
Elements of matrices A, B, and C can be obtained from above mathematical model-
ing/simulation block diagrams of Figures 15.
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Reactive Power Control of Hybrid Power Systems 1363
3. Simulation Results and Discussions
In this section, dynamic responses of wind-diesel hybrid power systems are presented.
In practical situation variation in reactive power load is not in step, but the variation
is realistic (step plus stochastic) in nature. There are number of realistic disturbancesavailable in Matlab/Simulink toolbox to simulate the realistic situation. In the present
case, step plus stochastic load disturbances, i.e., step plus normally (Gaussian) distributed
random signal, has been considered for the simulation of different configurations of
autonomous hybrid power systems and stochastic disturbance is properly adjusted by
multiplying suitable value of constant K10, as shown in Figures 24. The dynamic
responses of some of the system variables are shown for the optimum gain settings for
the autonomous hybrid power systems and are compared in terms of first swing amplitude
and settling time, etc.
The dynamic responses for 1% realistic increase in reactive power load plus 1%
step increase in input wind power with SVC type-I, type-II, and type-III are shown
in Figures 6, 7, and 8, respectively. Figures 9 and 10 show the dynamic responses
for 1% realistic increase in reactive power load plus 1% step increase in input wind
power with SVC type-II for multi-wind-diesel and wind-multi-diesel hybrid power systemrespectively. Figures 68 show the small deviations in terminal voltage ( V), reactive
power supplied by SVC (QSVC), reactive power supplied by synchronous generator
(QSG ), and reactive power absorbed by induction generator (QI G), in parts (a), (b),
(c), and (d), respectively. Figure 9 shows the small deviations in V, QSVC, QS G , and
power absorbed by induction generators (QI G 1 and QIG 2); and Figure 10 shows
the small deviations in V, QSVC, small deviations in power supplied by synchronous
generators (QSG 1, QS G 2) and QI G in parts (a), (b), (c), (d), and (e), respectively.
To get the dynamic responses with SVC type-II and type-III, SVC type-I in the simulation
block diagram can be replaced by SVC type-II and type-III of Figures 5(c) and 5(d),
respectively, in Figures 24. The maximum peak deviations of different parameters of
hybrid power systems have been presented in Table 1.
From Figures 610, it is observed that initially the synchronous generator provides
the reactive power required by the load, but substantially it is met by the SVC alone, andtherefore the steady state values of V and QS G become zero. It is also found from
Table 1 that the respective peak deviations are less with SVC type-II and SVC type-
III as compared with SVC type-I. The settling time is about 0.015 sec. for the system
responses with SVC type-II, and SVC type-III, but with SVC type-I it is about 0.15 sec.
Table 1
The peak deviations of different parameters of wind-diesel hybrid system
System and
SVC type V QSVC QSG QIG
Wind-diesel, I 0.00187 0.02592 0.01374 0.00321
Wind-diesel, II 0.00184 0.02089 0.01356 0.00320
Wind-diesel, III 0.00184 0.02102 0.01356 0.00320
2 Wind-1 diesel, II 0.00203 0.02183 0.01438 0.00322 (IG 1)0.00071 (IG 2)
1 Wind-2 diesel, II 0.00087 0.01947 0.00618 (SG 1) 0.00308
0.00724 (SG 2)
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1364 R. Bansal and T. Bhatti
Performance of SVC type-II and type-III is better than SVC type-I in terms of first peak
deviations and settling time.
It is also observed from Figures 9 and 10 that the settling time remains almost same
as in previous cases. It is also seen that multiplicity in the wind power generation reduces
the reactive power performance of the system whereas multiplicity in the diesel generatorsystem improves the same. It is further observed from Figures 9 and 10 that performance
of SVC type-II and type-III is better than SVC type-I.
4. Conclusions
This article has presented the effectiveness of the application of Simulink tool for reactive
power control of autonomous wind-diesel hybrid power systems. Simulink is very effec-
tive and easy for studying and comparing the performance of the systems with different
types components, e.g., various types of SVCs and different types of disturbances, etc.
A reactive power control study of sample wind-diesel isolated hybrid power system with
three types of SVCs and multi-wind-diesel, wind-multi-diesel hybrid systems with SVC
type-II have been presented in this article. It is seen that performance of SVC type-II and
type-III is better than SVC type-I in terms of first peak deviations and settling time. It is
also observed that multiplicity in the wind power generation reduces the reactive power
performance of the system whereas multiplicity in the diesel generator system improves
the same.
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Appendix 1
The data of the wind-diesel, multi-wind-diesel, wind-multi-diesel hybrid power system,
system capacity/load, reactive power, synchronous generator, induction generator, exci-
tation system, and the SVCs under consideration are as follows in Table 2.
Table 2
Parameters of hybrid systems
Multi-wind-diesel
system
Wind-multi-diesel
system
System parameter
Wind-diesel
system IG 1 IG 2 SG 1 SG 2
System capacity/load
Wind capacity (kW) 150 150 50 150
Diesel capacity (kW) 150 150 150 75
Load (kW) 250 300 300
Base power (kVA) 250 300 300
(continued)
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1366 R. Bansal and T. Bhatti
Table 2
(Continued)
Multi-wind-diesel
system
Wind-multi-diesel
system
System parameter
Wind-diesel
system IG 1 IG 2 SG 1 SG 2
Synchronous generator
PS G (p.u. kW) 0.4 0.333 0.333 0.1667
QSG (p.u. kVAR) 0.2 0.162 0.162 0.081
Eq (p.u.) 1.1136 1.1242 1.1242 1.1083 () 21.05 17.2483 17.2483 6.91
E 0q (p.u.) 0.9603 0.9804 0.9804 1.01
V (p.u.) 1.0 1.0 1.0 1.0
xd (p.u.) 1.0 1.0 1.0 0.8
x0d
(p.u.) 0.15 0.15 0.15 0.12
T0do
(s) 5.0 5.0 5.0 5.0
Induction generator
PI G (p.u. kW) 0.6 0.5 0.1667 0.5
QIG (p.u. kVAR) 0.189 0.1343 0.0426 0.1343
PI W (p.u. kW) 0.75 0.63 0.21 0.63
IG (%) 80 80 80 80
r1 D r0
2 (p.u.) 0.19 0.19 0.55 0.19
x1 D x0
2 (p.u.) 0.56 0.56 1.6 0.56
s (%) 4.1 3.49 3.37 3.49
Load
PL (p.u. kW) 1.0 1.0 1.0
QL (p.u. kVAR) 0.75 0.75 0.75
pf (lag) 0.8 0.8 0.8
Reactive power data
QSVC (p.u. kVAR) 0.498 0.7649 0.6413
Qc (p.u. kVAR) 0.5727 0.87961 0.7375
(rad.) 2.4440 2.4452 2.45568IEEE type-I excitation system
KA 40 40 40
TA (s) 0.05 0.05 0.05
KF 0.5 0.5 0.5
TF (s) 0.715 0.715 0.715KE 1.0 1.0 1.0
SF (s) 0.0 0.0 0.0
TE (s) 0.55 0.55 0.55
SVC data
SVC type-I
T (s) 0.005 0.005 0.005Td (s) 0.00167 0.00167 0.00167
TR (s) 0.715 0.715 0.715
SVC type-IIT (s) 0.005 0.005 0.005
Td (s) 0.00167 0.00167 0.00167
T1 D T2 D T3 D T4 (s) 0.715 0.715 0.715
SVC type-III
T (s) 0.005 0.005 0.005
Td (s) 0.00167 0.00167 0.00167