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c P Ss Tcg
Review on Frequency Control of PowerSystems with Wind Power Penetration
Yuanzhang , mb EEE Zhaui ZHANG, Gujie LI, mb EEE and in LIN
Abstract-The ineing peneion of wind powe myinuene he fequeny iliy of powe yem. Theefoe,new onol heme e neey fo wind uine nd poweyem o uppo he fequeny onol. Cuenly, mo of hepulihed onol mehod n e lied ino 3 level, i.e.,
wind uine level, wind fm level nd powe yem level. Thewind uine level onol enle wind uine, piully hevile peed wind geneo, o povide dynmi epone ndpowe eeve fo he pimy fequeny onol yimplemening he ineil, doop o deloding onolle. Thewind fm level onol diiue he enl onol ommndfom he yem o he lol wind uine nd enegy ogeuni fo he deied geneion. The powe yem level onoloodine wind fm wih onvenionl powe pln fo heeondy onol o eove he fequeny o he efeene vluefe hn fo he no oodinion onol e. Thi ppepeen eview on he le udie in elion o he 3levelfequeny onol of powe yem wih wind powe peneion.
d rs-Cenl onol, oodinion onol,deloding onol, doop onol, fequeny onol, ineilonol, lol onol, powe yem, wind fm, wind uine
I. NTRODUCTON
IN recent years, power systems are facing more equencystabili challenges with large-scale wind power integrating
into the grid. Synchronous generators can automatically
regulate the speed governors to support frequency control.
However, wind generators provide small or even no
contributions to equency stabili. Therefore, the equency
control schemes are required to be well designed for the
system with wind power to maintain the equency deviating
inside the appropriate region.
For a equency drop event, three securi indices, i.e.,
equency change rate, equency nadir ad steady stateequency deviation [1][2] and their impact factors are taken
into account in this paper. The equency change rate is
determined by the inertia of the whole system; The equency
nadir is determined by the power disturbance, the kinetic
energy of the rotating masses, the number of generators
subjected to prima control and the dynamic characteristics
of the generators, loads and controllers; The steady state
equency deviation is determined by the droop characteristics
This work was supportd in part by National Natural Scinc Foundationof China (50977050)
Th authors ar om Stat K Laborato of Powr Sstms, Dpartmntof Elctrical Enginring,Tsinghua Univrsity, Bijing 100084, P China
(-mail: zhangzs05@mailstsinghuaducn).
978597/ /$6 EEE
of all generators. Chinese standard [3] requires the maximum
equency excursion of 0.2 Hz. This excursion can berelaxed to 0.5 Hz if the system capaci is small.
The equency control of power systems is usually formed
of prima control and seconda control [1][4]-[7]. The
primary control is an automatic adjustment of power by thelocal control and inerial response of the generators and loads
within 30 seconds [4][5]. The instantaneous power and power
consumption are balanced so the equency is re-established
by the primary control aer a equency event. However, the
re-established equency is usually dierent om the
reference value. In the secondary control, the speed droop
characteristics of the generators are increased or decreased by
the operators or automatic generation control (AG).
Therefore, the equency can be reset to the reference value
om 30 seconds to 30 minutes aer a equency event [4].
This paper presents a review on the participation of wind
power for the prima and seconda equency control.
According to the latest studies, the control schemes can bedivided into a 3-level hierarchy, i.e., wind turbine, wind farm
and power system level controls. On the rst wind turbinelevel for the prima control, the additional local controllers
including inertial, droop and deloading controllers are
installed on the power electronic converers of variable speed
wind turbines or the pitch controllers of all kinds of wind
turbines. The inertial control supports the equency control in
the transient process. The droop control simulates the similar
equency droop characteristics to that of synchronous
generators. The deloading control provides the power reserves
for the wind farm. On the second wind farm level, the desired
generation for the system is achieved in the cooperation of
central control and local control. The central controller
receives the power command om system operators or AGC,and then distributes this command to the local controllers of
the wind turbines ad energy storage units in the wind farm.
On the third power system level for the seconda control, a
better equency behavior is obtained by the coordination
control between the AGC-controlled thermal plants and the
wind farms. The thermal plants can be started earlier by the
coordination controller to support the equency control and
the equency can be recovered to 50 H faster than for the nocoordination case.
II.ND RBNE EVEL ONTROL
Wind turbines can be divided into xed speed and variable
speed categories. A xed speed wind turbine generally utilizes
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a turbine, a gearbox and a squirrel-cage induction generator to
convert the mechanical energy into electrical energy. With a
low normal slip of 1%-2% [8], a xed speed wind turbine can
provide an inertial response to the equency uctuation due
to the coupling between the rotational speed and system
equency. Thus, the integration of xed speed wind turbinesincreases the system inertia, however, the inertial response is
generally smaller and slower than that of synchronous
generators [8][9].
Variable speed wind turbines mainly refer to permanent
magnet synchronous generators (PMSGs) and doubly fed
induction generators (DFIGs). A PMSG contains a multi-pole
magnet rotor and a back-to-back ACDCAC converter
attached to the stator. Consequently the generator is fully
decoupled om the grid. The energy is transmitted through
the converter om the stator to the grid. DFIGs that are more
common than the other wind turbine technologies also use
power electronic converters, however, attached to the rotors.The rotor that supplies the AC excitation current is connected
to the power system through the converter while the stator is
connected directly to the power system [10].
The power electronic converters enable the variable speed
wind turbines to capture wind energy over a wide range of
wind speeds, improve the power quali and regulate both the
active and reactive power. However, the decoupling control
isolates the rotational speed om the system frequency so the
variable speed wind turbines oer no response to the
equency excursion [8]. Another problem is that traditional
wind turbines always operate at the maximum power point
tracking (MPPT) so they store no power reserves to support
the equency control in the steady state.In the wind turbine level control, additional controllers are
installed on the converters of variable speed wind turbines or
pitch controllers to relate the electromagnetic torque andequency. The wind turbines transiently support the
equency control by implementing the inertial control which
is obtained by the approaches of "hidden inertia emulation
and fast power reserve emulation. The droop control simulates
the similar equency droop characteristics to that of
synchronous generators. The deloading control enables the
wind turbines to operate over deloading curves instead of the
MPPT and saves the available power as reserves by using
pitch control (pitching) or increasing the rotational speed fromthe MPPT value (overspeeding). The power reserves can
balance the instantaneous power and provide the permanent
support for the long-term frequency regulation. Therefore,wind generators are able to participate in the primary
equency control by using the wind turbine level control
A Inertial Control
(a) "Hidden inertia emulationThe basic reason for emulating the "hidden inertia is to
reduce the maximum equency change rate [11].
Synchronous generators and xed speed wind turbines can
automatically release the kinetic energy of the rotating mass
for a sudden equency change while variable speed wind
2
turbines cannot due to the decoupling operation [12].
However, a variable speed wind turbine can emulate the
similar inertia to that of synchronous generators by
implementing the inertial controller as shown in Fig. 1 [13].
P MT Pre f 1-- --- :f-" ____
Fig. I. "Hiddn inrtia mulation for variabl spd wind turbins.
The inertia constant is always used to express the inertial
characteristics. The so-called "hidden inertia of variable
speed wind turbines is estimated by [12][14]:
JOom2
(1)
where S is the nominal apparent power, Onom is the nominalrotor rotational speed and J is the equivalent moment of
inertia. The "hidden inertia is comparable to the inertia of
conventional generators [15]. For a two-mass mechanical
model used in this work, Jis [10][16]:J Jlr n2 +Jgen (2)
where n is the gearbox ratio, .r is the turbine moment ofinertia and Jgen is the generator moment of inertia. For a 2 MWwind turbine, the total moment of inertia is approximately six
times of that of the conventional generator [17]. The active
power control signal (inertial power) Pin of the inertial controlis achieved by [12][14]:
dsysn 2 x sysxdt
where Osysis the system rotational speed.
(3)
The wind turbine can fast store or release a large amount of
kinetic energy in the rotating mass because of the power
electronic converter control, large moment of inertia and wide
rotational speed range. Variable speed wind turbines can
considerably release greater kinetic energy than xed speed
wind turbines and conventional generators can [12][15].
Fast power reserve emulation
In fact, the inertial power is just a control signal and it canbe dened in dierent forms om (3) For example [5]
dened the inertial power as a constant power of 10% nominal
active power for 10 seconds over a wide operation range for
an E-82 2 MW wind energy converter. The short-term
constant power which is called "fast power reserve can
support the equency control for a short while [15][18][19].
The fast power reserve Potis derived om [18]:1 2 1 2ons'! 'JOro -'JOrt (4)
where t (t < tm is the lasting time of the fast power reservesince the beginning of the equency event, O is the initialrotor rotational speed and O is the rotor rotational speedcorresponding to t Thereby the reference rotor rotational
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speed in Fig. 2 is obtained by:
.-{r,re/ ={ = rO2 2 C;f
!
(5)
v :
Fig. 2. Fast pr rsrv mulatin fr variabl spd ind turbins.
The fast power reserves compensate the power loss for a
short period and save time for other slower generators to
participate in the equency control [18].
B. Droop Control
The droop control is described by the equency droop
characteristics in Fig. 3 [20] to produce an active poweroutput change which is proportional to the equency
deviation [14][21][22]. The equency deviation is given by:
=Ime - Jom (6)where Imeas is the measured system equency and fom is thenominal system equency (reference equency). The active
power control signal (active power increase) of droop control
is obtained by:
M=P= (7)
wwhere R is the speed adjustment rate, P is the total activepower corresponding to Imeas and is the initial total active
power corresponding tofom.
m
Fig. 3. Frquncy drp charactristics.
One application of droop control is to be implemented in
the converter of variable speed wind turbine as shown in Fig.
4 [14]. However, the power increase P which is absorbed
om the kinetic energy causes the rotational speed decrease
due to the MPPT operation. The turbine may stall if the
rotational speed is falling too low. This phenomenon may not
be avoided because the wind turbine cannot provide extra
permanent power to reduce the equency deviation [9].
Therefore, the droop controller should be ended on time like
the fast power reserve emulation.
--------------------
: D if 1___-i:. l ____________________ J
+
3
P M + Pf II.:I Cv L ____ .
Fig. 4. Drp cntrl fr variabl spd ind turbins.
Another application is to use the droop control with the
deloading control that is presented in Section II-C. Droop
control does not affect much initial equency change rate but
greatly inuences the equency nadir [16].
Deloading ControlTraditional wind turbines always operate on the PT
curve in Fig. 5 to extract the wind energy as much as possible.
The deloading control enables wind turbines to operate overdeloading curves instead of the MPPT and save the available
power as reserves for the long-term equency control. The
deloading possibilities are obtained by pitching and
overspeeding as shown in Fig. 5 [23]-[25]. The active power
can be changed by regulating the pitch angle om {min to alarger value { for a constant wind speed Vw and constantrotational speed. The power can also be changed by increasing
the rotational speed over the MPPT speed for a constant wind
speed Vw and a constant pitch angle {min'
p MT .
Fig. 5. Dlading pssibilitisvrspding and pitching.
In fact, decreasing the rotational speed below the PT
speed (underspeeding) in Fig. 5 is as well as a deloading
possibility. However, underspeeding may decrease the smallsignal stabili while overspeeding improves the small signal
stability compared with pitching [23]. Meanwhile, the rotor
has to rstly absorb extra energy om the grid and increase
the rotational speed which may lead to a second equency
drop. Therefore, overspeeding is preferable [24][25].
(aJ Pitch controlTraditional pitch control is valid when the rotational speed
is above the maximum value for a high wind speed condition
as shown in Fig. 6 [10]. Fig. 7 shows a kind of modied pitch
control which is widely used at present to store power reserves
for wind farms [13][26]-[28].
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x
Fig. 6. Traditional pitch contrl.
Fig. 7. Modid pitch contrl.
The pitch control is feasible for both variable speed and
xed speed wind turbines. The response of pitch control is
slower compared with the system frequency dynamics because
of the mechanical time constant of the pitch controller [11].
) Rotational speed controlOverspeeding is achieved by the rotational speed control in
Fig. 8 which is more convenient than pitch control when the
rotational speed is below the maximum value [11][23]. In
addition, overspeeding can protect the pitch blade om wear
and tear compared with only pitching for the low wind speed
condition [23]. However, the wind speed is difcult to be
accurately measured [25].
Fig. 8. Rotational spd control for variabl spd wind turbins.
Unlike pitch control which involves the servo time constant,
rotational speed control is obtained by the power electronic
converter of the variable speed wind turbine in a considerably
faster manner [11].
D. Discussion
The equency change rate is decreased by the inertial
control during the transient process. The frequency nadir is
increased by inertial control and droop control. The steady
state equency deviation is reduced by the deloading control
[14][21][22][29]. Therefore, the three equency securityindics may b maintaind at th appropriat valus if th
inertial, droop and deloading controllers are applied together.
In the inertial and droop control, the rotational speed rstly
decreases because the kinetic energy is released to the grid.
Therefore, the controllers should be ended on time to prevent
the turbine om stalling by decreasing the rotational speed
below the lower limit.
The loading of generators also aects the dynamic response
of the wind turbines in the MPPT operation. For instance, [16]
showed that DFIG could barely provide the required inertial
response without exceeding the rotor current limit if the
MPPT power were over 80% rated power. At rated power, thedynamic contribution is restricted because the rotor current is
4
already around its maximum value ad it cannot be much
rther increased. Therefore, the deloading control is
necessa not only to keep power reserves but also to improve
the capabili of dynamic response.
III. ND F EVEL ONTROLThe overall model of wind farm level control is built up
with a hierarchical structure of central control and local
control as shown in Fig. 9 [6][30]-[32]. The central controller
receives the active power command PWF om the operators orAGC (secondary control). Aer that, PWF is distributed to thelocal controllers of wind turbines and energy storage system
(ESS) units for the desired generation. The local controller
ensures the distribution signal and sends the feedback
information of generation capabilities to the central controller.
Pwn'" j
MT1Wd fam poe commad distbutio
AESS1
La
Ca
Fig. 9. Wind farm lvl control hirarchcntral control and local contrl.
A Local Control
The local control scheme use either a number of deloaded
wind turbines or ESSs in a wind farm [31][32]. The deloading
control proposed in Section II-C receives the control
command om the wind farm in Figs. 7 and 8 for the
seconda equency control.=GiFig. 10. Distributd ESS and aggrgatd ESS.
There are basically two ESS congurations in a wind farm
as shown in Fig. 10 [32], i.e., (a) one large aggregated ESS
which is directly connected to the grid based on the exteal
and non-wind technologies like batteries, compressed-air and
pumped hydro [33] for the whole wind farm and (b) several
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small distributed ESSs which are installed on the variable
speed wind turbines by implementing the devices such as
baeries [34], ywheels [35] and supercapacitors [36]. The
distributed ESS on PMSG is similar to that on DFIG in Fig.
10 and is also connected to the DC part of the ACDCAC
converter. [32] showed that the distributed ESS was aseective as the aggregated ESS in frequency deviation
reduction.
The choice of ESS depends on the demands of the control
process. From the point of view of reaction time, there are fast
and slow energy storage devices. From the point of view of
capacity, i.e., the length of operating time, there are short-,
medium- and long-term energy storage devices. For equency
control, fast and medium-term ESS is suitable [31].
B. Central Control
The set point PWF of system command should beappropriately allocated to wind turbines and ESS units by the
wind farm central control as follows:
P =PTlola + PSlola (8)where Ptta! is the total active power command for the wind
turbines and PESStta! is the total active power command for theESS units. The simplest distribution scheme is based on
equitable distribution, thus the output control signal for the i
th wind turbine is obtained by [6]:
- PMTii - tota nLPMi=
(9)
where PMTiis the generation ability (MPPT power) of the ith wind turbine corresponding to the wind speed. Similarly,
the output control signal for the j-th ESS is:
AEESjP =PSlola -k
LAEjj=1
where AESSj is the capacity of the j-th ESS.
(10)
[37] described another rough distribution method to restrain
the power uctuation which was caused by the random wind
speed. In short, the higher the wind speed is, the larger the
weighting factor for the wind power output is. Therefore, the
output control signal for the i-th wind turbine under wind
speed Vw is given by:
= .W(Vw)xN(Vw)
._1_i lola LW(Vw)xN(Vw) N(Vw) (11)where (Vw) is the number of wind turbines operating at windspeed Vw and W(Vw) is the weighting factor for each level ofwind speed, e.g., assuming that the wind speed range is 15ms in the wind farm, separate the range into 5 levels and
dene 11 ms = , 112 s = 2, ..., 415 ms= 5. Therefore, the wind turbine under higher wind speed is
roughly assessed to provide more power than the wind turbine
under lower wind speed. The wind speed uctuation is not
considered any rther in this paper.
. Discussion
As mentioned in Section II-B and D, the inertial control or
5
droop control should be ended on time to prevent the
rotational speed om falling too low. However, there will be asudden drop of the power output when switching o the
controller. The undesirable sudden drop may cause another
equency reduction especially when many generators end the
controllers together. The solution is to switch o eachcontroller at different time or by using a gradual change to
normal operation instead of the abrupt change [14][15][22].
The switching control can be completed by the modied wind
farm level control too. However, the set points of switching
time, inertial power of inertial controllers and speed
adjustment rates of droop controllers ae considered to be the
local control signals instead. The distribution strategy of the
modied wind farm level control is much more complex than
the equitable distribution ad is determined by the current
rotational speed, the number of selected wind turbines and the
system requirement, etc.
Deloading of wind turbines means increased wear and tearof the blade and hub material due to the equent pitch control
[38] as well as a generation loss because not all available wind
energy is converted into electricity. The use of ESS reducesthe generation loss but leads to a higher investment and
maintenance cost. In addition, no energy storage is 100%
ecient which also cause some losses [31]. Therefore, the
economic benets need to be optimized considering the above
factors.
Actually, not all the wind turbines in the wind farm are
necessa to operate at deloading. The number of selected
wind turbines and their deloading extent, i.e., the ratio
between PWTttal and PESStta! in (8), are determined by the
system operation, wind speed, ESS capabili and economybenets.
The equency control support by ESS is limited due to the
little capacity of ESS. ESSs may reduce the equencyexcursion for a while but cannot permanently inuence the
steady state equency. Therefore, conventional power and
wind power should be rectied to support the long-termequency control [31].
The wind farm level control can send the appropriate
commands to the local generating units from a global vision.
In this strategy, the wind turbines can operate in the best
condition for the equency control which cannot be obtained
om the point of view of wind turbine level control.
IV. P SY L CN
So far, most of the studies are related to the wind turbine
and wind farm level controls and few studies focus on thesystem level equency control considering the wind power
penetration. Almost all of the relevant research on system
level control observed the impact of increasing wind power on
equency stability [2][8][39] or proposed the simple
coordination control method between the wind farm and
conventional plants [7][40].
In this paper, the equency control is deemed to be
composed of primary and secondary control during thedynamic and quasi-steady state processes within 30 minutes.
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Therefore, the economic dispatch, i.e., the so-called tertiary
control, is not taken into account.
A Wind-Thermal Coordination Control
The secondary control is concerned for the power system
level control to restore the equency to 50 Hz, so the loadreference should be regulated. The inertial control increases
the system inertia but the inertial power may mask the load
changes for a few seconds because of the considerably
released kinetic energy om the rotating mass. Therefore, the
synchronous generators may delay their responses to the
equency events [7].
A enhanced solution as shown in Fig. 11 [7][20][40] is tolet the AGC-controlled thermal plats be aware of the
equency control support by the wind farm as soon as
possible. The wind farm is equivalent to an individual wind
turbine with droop and inertial controllers. The two additional
controllers may be enough to improve the equency stabili.
However, the wind-thermal coordination control can achievean even better equency behavior. The droop control changes
the power reference of the wind farm as well as communicates
Wsys Ineial ontrol
6
with a selected set of AGC-controlled thermal plants through
the coordination control. The droop power P is distributed
by the coordination control as follows:"K =1L.el
(12)
(13)where Pci is the coordination control signal, Kci is theparticipation factor for each thermal plant supporting the wind
farm. Pcimodies the AGC error which is similar to the areacontrol error (ACE).
In this way, the thermal plants will realize the power
imbalance since the very beginning. Therefore, the thermal
plants will start earlier to support the equency control and
the equency can be controlled and recovered back to 50 Hz
faster than for the no coordination control condition.
The wind-thermal coordination control is based on the same
principle as the tie line bias control. However, the AGC error
uses the coordination control signal Pci instead of the tie linepower deviation.
Pc1
AGC.-6fPc; _J+)_- r----Ispd I govo IPeN Lod c
'--Wd frm
(quvt o sg wd ub)Coodato coto AGC-cood
ha pt
Fig. 11. Coordination control btwn wind f and thrmal plants.
B. Wind Power Penetration Impact on Frequency Stabili
During a equency drop, the inertial response of xed
speed wind turbines is much smaller and slower than the
inertial response of synchronous generators because the
allowable slip of 1%-2% for the wind turbine reduces the
coupling of the rotational speed and system equency. The
variable speed wind turbines without wind turbine levelcontrol show negligible inertial response due to the
decoupling between rotational speed and the system equency.
Therefore, the maximum equency change rate is sensitive to
the amount of installed wind power. The power system with
more wind power penetration leads to the greater equency
change rate which has little to do with the ratio between
variable speed and xed speed wind turbines. The equency
nadir for the system with only xed speed wind turbines
reaches the same level as for the no wind power condition.
However, the equency nadir is considerably lower if more
variable speed wind turbines are integrated into the grid. Thus,
the maximum equency change rate and equency nadir
events may increase in the future as the wind power
penetration increases. The additional controllers on the
variable speed wind turbines can effectively reduce the
equency change rate and nadir. The benecial eect of the
large amount of kinetic energy stored in wind turbines could
be of signicant importance if the energy were utilized in a
large-scale way [2][8][39].
ONCLUSONSThis paper presents a review on the equency control of
power system with wind power penetration. The control
strategies in the recent studies can be separated into wind
turbine, wind farm and power system levels.
The wind turbine level control supports the prima
equency control. The inertial, droop and deloading
controllers are installed on the power electronic converters of
variable speed wind turbines or pitch controllers of all kinds
of wind turbines. The inertial control emulates the "hidden
inertia or fast power reserve to slow down the equency
change rate in the transient process. The equency nadir can
be increased by both inertial control and droop control. Thedeloading possibilities are achieved by two approaches of
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overspeeding and pitching. The deloading control stores the
deloaded power as reserves for the wind farm to reduce the
steady state equency deviation. The restrictions of the wind
turbine level controllers are also discussed.
The wind farm level control is composed of central control
and local control. The central controller receives the activepower command om operators or AGe and distributes the
command to the local controllers. The local control refers to
the wind turbine deloading control and ESS control. The local
control ensures the distribution signal for the desired
generation of wind turbines and ESSs in the wind farm. The
modied wind farm level control is also presented to
overcome the restrictions of the droop control and inertial
control. The factors which affect the distribution strategy are
rther reviewed om the point of view of economy and
technology.
The power system level control supports the seconda
equency control. Only the wind-thermal coordination controlmethod is presented due to the little research in relation to the
area of system level control. The inertial power which is
released by the inertial control may transiently mask the load
changes and the thermal plants may delay their response to the
equency events. However, the thermal plants can be started
earlier to support the wind farm by the coordination control
and the frequency can be recovered to 50 Hz faster than for
the no coordination case. The coordination control is based on
the same principle as the tie line bias control. The wind
penetration impact on the equency stability is also described.
Therefore, the equency securi indices of change rate,
nadir and steady state deviation are maintained at the
appropriate values by using the 3-level control methods.
VI. ACNOLEDENTS
This work was supported by Vestas Technology R&DSingapore Pte Ltd.
VII. EFERENCES
[I] J. Morrn, "rid support by powr lctrnic convrtrs of distributdgnration units, Ph.D. dissration, Dl Univrsity of Tchnology,Nthrlands, 2006.
[2] Dohrty, . Mullan, . Lalor, D. J. Burk, . Byson, ad M.O'Mally, "n assssmnt of th impact of wind gnration on systmfrquncy control, IEEE Trans. Power Syst. vol. 25, no. I, pp.452460,
Fb. 2010.[3] Power qualiFrequency deviation for power system ChinsStandad BT 15945-2008,Jun. 2008.
[4] . Moor, and J. Ekanayak, "Frquncy rspons om wind turbins,in UPEC 2009, pp. 15.
[5] S. Wachtl, and . Bkmann, "Contribution of wind nrgy convrrswith inrtia mulation to frquncy control and frquncy stability inpowr systms, prsntd at th 8th nt. Workshop on Larg Scalntgration of Wind Powr into Powr Systms as wll as on OshorWind Fams,Brmn,rmany,Oct. 2009.
[6] . D. Hansn, P. Sornsn, F. ov, and F. Blaabjrg, "Cntralisd powrcontrol of wind fam with doubly fd induction gnrators, Renewable
Ener no. 31,pp. 935-951,2006.[7] J. M. Mauricio, . Marano, . mz-Expsito, and J. L. M. Ramos,
"Frquncy rgulation contribution through variabl-spd wind nryconvrsion systms, IEEE Tns. Power Syst. vol. 24, no. I, pp.173180,Fb. 2009.
7
[8] . Lalor, . Mullan, and M. OMally, "Frquncy contrl ad windturbin tchnologis, IEEE Tns. Power Syst. vol. 20, no. 4,pp.19051913,Nov. 2005.
[9] J. Duval, and B. Myr, "Frquncy bhavior of grid with highpntration rat of wind gnration, in PowerTech 2009, pp. 16.
[I] V. khmatov, "nalysis of dynamic bhavior of lctric powr systmwith larg amount of wind powr, Ph. D. dissrtation,Elct. Powr Eng.,rstd-DTU,Tchnical Univ. Dnmark, Lyngby, Dnmark,pr. 2003.
[II] . Ramtharan, J. B. Ekanayak, and N. Jnkins, "Frquncy supportfrm doubly fd induction gnrator wind turbins, ET Renew. PowerGener., vol. I,pp. 39,2007.
[I2] J. Ekaayak, and N. Jnkins, "Comparison of th rspons of doublyfd and xd-spd induction gnrator wind turbins to chags inntwork frquncy, IEEE Trans. Ener Convers. vol. 19, no. 4, pp.80802,Dc. 2004.
[13] L. Holdsworth, J. Ekanayak, and N. Jnkins, "Powr systm quncyrspons frm xd spd and doubly fd induction gnrator basdwind turbins, Wind Ener vol. 7,pp. 2135, 2004.
[I4] J. Morn, S W. H. d Haan, W. L. Kling, and J. . Frrira, "Windturbins mulating inrtia and supporing primary quncy control,IEEE Trans. Power Syst. vol. 21, no. I,pp. 433434,Fb. 2006.
[15] P. K. Kung, P. Li, H. Bakar, and B. T. Ooi, "Kintic nrgy of windturbin gnrtors for systm frquncy suppor, IEEE Trans. Power
Syst. vol. 24,no. I,pp. 279287, Fb. 2009.[I6] M. Kayikci, and J. V. Milanovic, "Dynamic contribution of DF-basd
wind plants to systm quncy disturbc, IEEE Tns. Power Syst.vol. 24,no. 2,pp. 859867,May. 2009.
[17] B. H. Chowdhury and H. T. Ma, "Frqun rgulation with wind powrplants, inPESGM 2008 pp. 2135.
[18] . Tning, C. Jcu, D. Roy, S. Bacha, J. Duval, ad Blhomm,"Contribution to frquncy contrl through wind turbin inrial nrgystorag, ET Renew. Power Gener., vol. 3,pp. 358370,2009.
[I9] N. Ullah, T. Thiringr, and D. Karlsson, "Tmporay primayfrquncy control support by variabl spd wind turbinspotntialand applications, IEEE Trans. Power Syst. vol. 23, no. 2, pp. 60112,May. 2008.
[20] P. Kundur, "Powr systm stability and control, Nw York: McrawHill,1994.
[21] B. H. Chowdhu, and H. T. Ma, "Frquncy rgulation with wind
powr plants, in Power and Ener Society General Meeting -Conversion and Delive of Electrical Ener in the 21st Centu, 2008IEEE, pp. 15.
[22] J. F. Conroy, and Watson, "Frquncy rspons capability of fullconvrr wind turbin gnrators in comparison to convntionalgnration, IEEE Tras. Power Syst. vol. 23, no. 2, pp. 649656, May.2008.
[23] N. . Janssns, . Lambin, and N. Bragard, "ctiv powr contrlstratgis of DF wind turbins, PowerTech 2007, pp. 51521.
[24] E. Loukarakis, . Margaris, and P. Moutis, "Frquncy contrl supportand participation mthods providd by wind gnration, in EPEC 2009,pp. 1.
[25] P. Moutis, E. Loukarakis, S. Papathanasiou, and N. D. Hatziargyriou,"Primary load-frquncy control frm pitch controlld wind turbins, inPowerTech 2009 , pp. 17.
[26] . d lmida, and J. . Pas Lops, "Paricipation of doubly fd
induction wind gnrtors in systm quncy rgulation, IEEE Trans.Power Syst. vol. 22,no. 3,pp. 944950, ug. 2007.[27] Sakamoto, T. Snjyu, N. Urasaki, T. Funabashi, and H. Fujita,
"Output powr lvling of wind turbin gnrators using pitch anglcontrol for all oprating rgions in wind farm, in 13th Int. Co onP '05 pp. 367-372, rlington V,US.
[28] . d lmida,E. D. Castronuovo,and J. . Pas Lops, "Optimumgnration control in wind parks whn carying out systm opratorrqusts, IEEE Tns. Power Syst. vol. 21, no. 2, pp. 718725, May.2006.
[29] . d lmida, and J. . Pas Lops, "Primary quncy contrlparticipation providd by doubly fd induction wind gnrators, inProc. 15th Power Systems Computation Con! Lig, Blgium, ug.2005.
[30] J. L. Rodriguz-mndo, S. alt, and J. C. Burgos, "utomaticgnration control of a wind farm with variabl spd wind turbins,IEEE Trans. Ener Convers. vol. 17,no. 2,pp. 279284,Jun. 2002.
-
7/27/2019 Review on Frequency Control of Power Systems With Wind Power Penetration51
8/8
[31] Z. Lubosny, and J. W. Bialk, "Suprvisoy control of a wind farm,IEEE Trans. Power Syst. vol. 22,no. 3,pp. 985994, ug. 2007.
[32] L. Wi, and . Joos, "Prformanc comparison of aggrgatd anddistributd nrgy storag systms in a wind farm for wind powructuation supprssion, in Power Engineering Socie General Meeting,2007 IEEE, pp. 16.
[33] F. . Bhuiyan, and . Ydani, "Multimod contrl of a DF-basdwind-powr unit for rmot applications, IEEE Trans. Power Syst. vol.24,no. 4,pp. 20792089,Oct. 2009.
[34] M. ktarujjaman, M. . Kashm, M. Ngnvitsky, and . Ldwich,"Control stabilisation of an islandd systm with DF wind turbin, in,pp. 312317
[35] . O. Cimuca, C. Saudmont, B. Robyns, and M. M. Radulscu,"Control ad prformanc valuation of a ywhl nrgy-storagsystm associatd to a variabl-spd wind gnrator, IEEE Tns. In
Electron. vol. 53,no. 4,pp. \074\085, ug. 2006.[36] C. bby and . Joos, "Suprcapacitor nrgy storag for wind nrgy
applications, IEEE Trans. Ind. Appl. vol. 43, no. 3, pp. 769776,May/Jun. 2007.
[37] L. Chang-Chin, and Y. Yin, "Stratgis for oprating wind powr in asimilar mannr of convntional powr plat, IEEE Trans. EnerConvers. vol. 24,no. 4,pp. 926934, Dc. 2009.
[38] L. Chang-Chin, C. Hung, and Y. Yin, "Dynamic rsrv allocation for
systm contingncy by DF wind farms, IEEE Tns. Power Syst. vol.23,no. 2,pp. 729736,May. 2008.
[39] . Lalor,J Ritchi, S. Rourk, D. Flynn, and M. J O'Mally, "Dynamicquncy contrl with incrasing wind gnration, in Power
Engineering Socie Genel Meeting, 2004 IEEE, pp. 17151720.[40] J. Cao, H. Wang, J. Qiu, "Frquncy control stratgy of variabl-spd
constt-frquncy doubly-fd induction gnrator wind turbins,Automation of Electric Power Systems vol. 33, no. 13, pp. 7882, Ju.2009.
VIII.ORPHES
Yuan-zhang SUN (M99SM01) rcivd th B.S. dgr frm WuhanUnivrsity of Hydro and Elctrical Enginring, China, th M. S. dgr frmElctric Powr Rsarch nstitut (EPR), China, ad Ph.D. dgr om
Tsinghua Univrsity, Bijing, in 1978, 1982, and 1988, rspctivly, all inlctrical nginring. H is now a chair profssor at Tsinghua Univrsity anddan of School of Elctrical Enginring at Wuhan Univrsity. His mainrsarch intrsts ar in th aras of powr systms dynamics ad contrl,voltag stability and control, ad rnwabl nrgy.
Zhao-sui NG rcivd th B.S. dgr in lctrical nginring omTsinghua Univrsity, Bijing, P. R. China in 2009. H is now a Ph. D.candidat at Tsinghua Univrsity. His main rsarch intrsts ar rnwablnrgy and th stability analysis on powr systms.
Guo-jie LI rcivd his B.S. and M.S. dgrs in Elctrical Enginring fromTsinghua Univrsity, P.R. China in 1989 and 1993, rspctivly. H alsorcivd Ph. D. dgr in th School of Elctrical and Elctrnic Enginring,Nanyang Tchnological Univrsity Singapor in 1999. H is now an associat
prfssor in th Dparmnt of Elctrical Enginring, Tsinghua Univrsity, P.R. China. His currnt rsarch intrsts includ powr systm analysis andcontrol, wind powr analysis d control, and powr quality.
Jin LIN rcivd th B.S. dgr in lctrical nginring om TsinghuaUnivrsity, Bijing, P.R. China in 2007. H is now a Ph. D. candidat atTsinghua Univrsity. His main rsarch intrsts ar rnwabl nrgy and thstability analysis on powr systms.
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