Out-of-Step Detection based on Phasor Measurement Unit
ZAID S. AL-SHAMAAIN1, HUSSEIN. D. AL-MAJALI1, BILAL. H. AL-MAJALI2
1Department of Electrical Engineering, Faculty of Engineering
Mu’tah University,
Al-Karak,
JORDAN
2Electronic and Electrical Engineering, Faculty of Engineering
Brunel University London,
Uxbridge,
UNITED KINGDOM
Abstract: - The electrical power systems operate as a huge, interconnected network that extends across a large
area. In the power system, there is an equilibrium between generated power and a load. Any disturbance in the
system, such as a fault or a change in load, will lead to imbalance and electromechanical oscillations. As a
result, the power flow between two areas varies. This is known as a power swing." Large system disturbances
could lead to large rotor angle deviations between groups of generators, resulting in a loss of synchronism
between generators or between interconnected systems. This is known as an out-of-step condition. To avoid
equipment damage and power outages, the interconnected area must be isolated as soon as possible before the
electrical system loses synchronization. In this paper, PMU data is used to measure the current, voltage, and
phase angle of the three phases at both ends of two interconnected area power systems. The measured data is
then used to distinguish between a power swing or fault condition and predict the future phase angle difference
during the disturbances to evaluate the system stability condition. If a swing is detected, then it will be
ascertained whether the swing is stable or not. The performance of the proposed method has been tested on a
simulated system using MATLAB / Simulink software.
Key-Words: - Phasor Measurement Unit, Current Detection Element, Phase Angle Difference, Phasor Current
Difference, Out of step trip, Stability system.
Received: November 25, 2022. Revised: November 26, 2023. Accepted: December 12, 2023. Published: December 31, 2023.
1 Introduction
Typically, power systems operate near or at their
nominal frequency. Under steady-state operation,
there is a balance between generated and consumed
active and reactive powers. However,
electromechanical oscillation will occur when the
system recovers from disturbances caused by faults,
line switching, generator disconnections, or a
change in a large load. During this time, the rotor
angle varies. If the swing is stable, the fluctuations
will decrease. During severe disturbances, however,
the oscillations do not remain stable, resulting in
even more angle separation between the areas. This
results in large swings in power flow as well as
changes in voltages and currents. Eventually, there
is a loss of synchronization, often known as an out-
of-step condition, [1].
During power swing, the load impedance
may cross the operating zone of the relay, causing
unwanted tripping of transmission lines and
cascading outages and power blackouts, [2], [3]. In
the case of a power swing, the Power Swing Block
(PSB) acts to block distance relay element
operation, allowing the power system to return to a
stable operating condition, [4], [5]. The PSB's
primary function is to distinguish between fault and
power swing.
Out of step trip (OST) distinguishes between
stable and unstable power swings and
initiates system area separation at predetermined
network nodes. When an interconnected area system
loses synchronization, the areas must be separated at
predetermined places to maintain load generation
balance, avoid equipment damage, and power
outages. To maintain the stability of the power
system, [6], [7], [8].
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
354
Volume 18, 2023
A difference in the rate of change of the positive
sequence impedance vector has traditionally been
applied to the PSB and OST to detect power swings
and out-of-step conditions. The operation of
distance relays starts before the impedance enters
the operating zone of the protective relay. The
traditional method for detecting power swing is to
measure the rate of change of impedance and the
time it takes for the impedance vector to pass
through a particular zone. When the impedance
vector enters the zone, a timer starts and stops when
it leaves. If the time taken for measurement exceeds
the preset value, a power swing is detected.
A current differential protection technique that
can detect faults in a transmission line by comparing
the instantaneous current data collected from PMU
at both ends of the line has been provided in, [9],
[10], [11]. It works effectively when intercircuit and
cross-country faults are evolving. It also works for
faults that occur during power swings.
The load angle measurements of synchronous
generators can be utilized to detect an out-of-step
condition, [12]. The suggested method measures the
phase difference of the positive sequence voltages
using an estimation algorithm, [13] and PMU data,
[14], [15], at both ends. When the estimated phase
angle value exceeds a threshold value, the power
swing is assumed to be unstable, and the system
loses synchronism.
To detect a power swing as well as current fault
with high accuracy and evaluate the system
performance, in this paper an out of step detection
method is proposed simultaneously using positive
phase angle difference and positive sequence current
from the PMU measurements placed at both end of
the interconnected area.
This paper is organized in five sections: section
1 presents a brief overview of power swing
phenomena and distance relay element operation;
section 2 presents conventional power swing
detection methods; and section 3 presents the
proposed detection method, the proposed detection
algorithms, and their performance. The simulation
results and discussion are presented in Section 4, and
finally, the conclusion is organized in Section 5.
2 Conventional Power Swing
Detection Methods
There are several methods that are proposed to detect
out-of-step condition in a power system based on
local-measurements. These methods are briefly
summarized next.
2.1 Conventional Rate of Change of
Impedance
During normal system operation, the measured
impedance is the load impedance, and its locus is far
from the relay operating zone, [16]. When a fault
occurs, the impedance point moves instantaneously
into the relay operating zone; however, during a
power swing, the impedance point moves slowly on
the impedance plane. The elapsed time required by
the impedance vector to pass through a zone is
limited by two additional concentric impedance
characteristics that are used to calculate the rate of
change of impedance. The inner concentric zone
setting should be larger than the largest tripping
characteristic, [17], [18], [19].
Power swing can be detected before the
impedance locus enters the operational
characteristic, which is advantageous. The important
parameters in this method are the delta impedance
and the timer. To find the optimal settings, extensive
stability studies are required. The drawback is that
the maximum load of the transmission line is limited
by the outer zone. This is referred to as load
encroachment.
2.2 Continuous Impedance Calculation
The power swing is determined using a continuous
impedance calculation in this method. For instance,
an impedance calculation is performed for each 4ms
time step and compared to the previous step's
impedance. If there is a deviation, the system is
considered to be out of synchronization. The next
step's impedance is predicted based on the previous
two values. If the prediction is correct, a ten-power
swing is detected. This technique doesn't require the
use of delta time or delta impedance settings. The
detection might fail if the changing impedance
vector is faster than the relay processing speed, [16].
2.3 Blinder Schemes
A. Single blinder scheme
A single blinder method uses only one set of blinder
characteristics. It can also be utilized with auxiliary
logic for out-of-step trip functions. However, it can't
differentiate between a fault and an OOS condition
until the fault has passed through the second blinder
within the given time limit. When an unstable power
swing is detected, this approach can be utilized to
prevent automatic reclosing. The primary advantage
of this method is that it may be used to prevent load
encroachment, [20].
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
355
Volume 18, 2023
B. Dual blinder scheme
The two-blinder scheme and the concentric
characteristics scheme both operate on the same
basis. When the impedance vector passes through
the outer blinder, the timer starts and stops when it
passes through the inner blinder. If the measured
time exceeds the delta time settings, a power swing
is detected. All elements of distance will be blocked.
If an unstable power swing is detected, the mho
element may trip immediately or after the swing has
passed through, [21], [22]. The advantage of this
technique is that the distance protection settings
have no effect on the power swing detection
settings. However, determining the optimal settings
requires extensive stability studies.
2.4 R-Rdot Scheme
The R-dot scheme is the apparent resistance rate of
change that is supplemented by the OST relay. The
control output of an R-dot relay is described as Y2 =
(R2-R1) + T1 dR/dT, where Y2 is the control output
and R is the apparent resistance measured by the
relay. R1 and T1 are relay setting parameters. When
the power swing trajectory crosses a switching line,
an output in the R-dot plane is generated. For
traditional OST relays, the apparent resistance rate
is enhanced by a vertical line in the R-dot plane
offset by R1, which is the relay setting parameter.
System separation occurs when output Y2 becomes
negative. For small dR/dT and low separation rates,
the R-dot method operates similarly to a
conventional relay scheme. However, for large
dR/dT, a larger negative value of Y2 is produced,
causing tripping to occur earlier due to the high
separation rates. The technique has the same
problems as the blinder scheme in that it requires
extensive simulation studies under various
contingency conditions to set the relay
characteristics. However, determining optimal
settings requires extensive stability analysis, [23].
2.5 Swing Center Voltage Method
The swing center voltage (SCV) technique is a
voltage-based method discussed in, [24]. When the
angular separation between two source-equivalent
systems approaches 180 degrees, the SCV is a point
of zero voltage between them. The electrical center
is the location of zero voltage.
The SCV approach calculates the maximum rate
of change of voltage at the electrical center.
Detection is normally accomplished at a voltage
angle separation of close to 180 degrees. When
tripping occurs under these conditions, the circuit
breaker is subjected to twice the rated stress. As a
result, the operation of the circuit breaker is delayed
until the voltage angle separation is
less. Furthermore, estimating the SCV using local
measurements of the voltage phasor is only valid
when the impedance angle is 90 degrees.
3 The Proposed Detection Method
The Kundur two area system, which consists of two
areas connected by two weak tie lines, is the most
suitable test system for the study of out-of-step
condition. The tie line serves as the system's
electrical center. If a fault happens on one of the tie-
lines, the power swing will be created with swing
center on the second tie-line.
The test system consists of four generators
divided into two symmetrical areas linked by two tie
lines. Area 1 has a load of 967MW and a generation
capacity of 1400MW. The load in Area 2 is
1767MW, and the generation is 1463MW. Each tie
line transfer approximately 200MW.
The relay is implemented at bus 1. Phasor
Measurement Units (PMU) are placed on buses 1
and 2. The line is tripped after a fault occurs on Tie
line -2. As a result, there is a power imbalance in the
other Tie line, causing power swing, During the
swing, another fault occurs in the line and is
detected by the current differential method. PMUs
placed at the buses calculate the voltage and current
of the three-phase line at a sampling rate of 64
samples per cycle. The PMU data is then used to
measure the positive sequence voltage and current
phasors using the Discrete Fourier Transform.
Fig. 1: Block diagram of simulated system
3.1 Out-of-step Detection Method
A. Phase difference calculation
The phase difference between the two area (Area1
and area 2) are obtained by calculating the phase
difference between the positive sequence voltage
data of the two ends from PMUs.
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
356
Volume 18, 2023
B. Calculation of predicted values of phase
difference
The prediction is obtained by using the phase
difference values for present time and previous time,
the future value can be predicted by the equations
below.
(1)
Where,
μ =
(5)
δp: predicted relative phase angle
δα, δβ: phase angles
The phase difference δp is predicted for time
TD using 8 data points as shown in Figure 2. These
are the phase difference at the present time δα and
three values (δα-1, δα-2, and δα-3) at negative
increments of time TD. Also, the phase difference
value δβ at the time TM before the current time and
three values (δβ-1, δβ-2, δβ-3) in the negative
increment TD at that time. Where TM is the time
difference that takes a sample point between δα and
δβ (in our case TM= 10ms and TD= 20ms), TD is
the time difference between each pair of sample
points.
Fig. 2: Method of predicting phase angle
When the predicted phase angle difference value
δp obtained by Eq.1 exceeds a critical threshold
value, then it’s judged that the power swing between
the two generator groups will lose synchronism. The
value δ_critical is predetermined by the system
configuration. The value chosen must be such that it
does not operate during a stable swing. The
predicted and measured values are shown in Figure
3. When the predicted phase angle difference value
exceeds a minimum threshold value, the power
swing is assumed to be unstable, and the system will
lose synchronism, [25]. The value of is determined
by the system conditions and is carefully chosen so
that the system does not malfunction during a stable
swing. Many research used new techniques to convert
DC to AC in order to link with grid, [26], [27] and other
research used to convert AC to DC were used HVDC
system, [28], [29], [30].
A current swing detection element, in addition
to the phase angle difference limit, should be
operated to confirm that the system will lose
synchronism in the near future. Figure 3 shows a
swinging condition with both actual and predicted
phase differences. The predicted value is 20ms
earlier than the actual value.
Fig. 3: Predicted and measured phase difference
In Figure 3, which illustrates the predicted and
measured phase angle difference values that are
almost closed to each other during the test of the
method's performance, that means the accuracy is
very high when applying the proposed prediction
method.
C. Current swing detection element
This element serves as a second check criterion to
determine the detected out of step from the
predicted phase difference value. By using a current
input to detect oscillation, it operates when the
swing is unstable and off when it is stable. Figure
4 shows the logical diagram of the current swing
λ =
(4)
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
357
Volume 18, 2023
detection element, Table 1 shows the logical
operation of current swing detection element during
power swing.
The current swing detection element consists of
two detection blocks: a magnitude of change
detection block to measure the size of the current
fluctuation and a rate of change detection block to
ascertain whether a power swing is present. The
element works with AND of these two blocks.
Fig. 4: Current swing detection element
Table. 1. logic operation of current swing detection
element, 1: operate, 0: not operate
The Imax and Imin are the maximum and
minimum values of the positive sequence current
during the predetermined time period ΔT max. The
magnitude of change detection block is operated if
Iset is greater than a predetermined value, Iset and
ΔT max are determined by simulation. ΔI / Δt
represents the rate of change of the current value
over the small-time interval Δt. The rate of change
detection block acts when ΔI / Δt is greater than a
constant N and continues for a longer period of time
than time T1. If both elements are operated, the
current swing detection element gives a positive
output, that means unstable power swing was
detected. ΔTmax=2 sec, Δt=5ms and T1=20ms.
3.2 Fault Detection Method
The main criterion for fault detection and load
conditions is the difference in positive sequence
current phasor at both ends. A threshold value is
determined by carefully comparing the steady-state
and power-swing condition. If the difference
exceeds a certain threshold, the algorithm detects a
fault.
3.3 Flow Chart of the Proposed Detection
Method
A proposed detection method for out-of-step
conditions based on the phase angle difference of
the positive sequence voltage and phasor current
difference of the positive sequence current from
PMU measurements is illustrated in the flowcharts,
which are shown in Figure 5 and Figure 6
respectively.
Fig. 5: Flow chart for the proposed out-of-step
detection method based on phase angle difference
The voltage phase angle from both PMUs at
both ends works as an input for the proposed flow
chart that is shown in Figure 5 After the phase
difference is calculated, the predicted phase angle
difference is obtained from equation (1), then the
predicted angle δp is compared with δ_critical to
determine the swing type, whether stable or not, to
provide a decision for out of step relays.
The phasor current magnitude from both PMUs
at both ends works as an input for the proposed flow
chart shown in Figure 6 after the phasor current
difference and current rate of change are calculated
at a predetermined time. The obtained values are
compared with the setting current and constant
factor N, then the swing type will be classified as
stable or not to provide a decision for out-of-step
relays, which works as a second check criteria with
the phase angle prediction algorithm that was
discussed before.
Power Swing Type
Output
Stable
0
un-stable
1
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
358
Volume 18, 2023
Fig. 6: Flow chart for the proposed out-of-step
detection method based on phasor current difference
4 Results and Discussion
The performance of the proposed detection scheme
has been tested on the system given in Figure 1.
A three-phase fault is a worst case that has been
created in the system in the case of a transient fault,
which has been created here at about 0.5s and
cleared at 1s and δ_critical = 100°, Iset value=
3.4kA. The predicted angle, actual angle, prediction
accuracy, and current swing element operation are
calculated at different sizes of fault (fault resistance
and ground resistance), and the phase angle
predicted value is very close to the actual value with
very high accuracy (around 99.9%) at stable or
unstable conditions, which is also compatible with
the current swing element operation.
Table 2 shows the simulation results of
predicted phase angle difference with actual phase
angle difference in degree and the prediction
accuracy at different sizes of faults.
When the predicted angle is greater than the
critical angle (in this case, δ_critical=100 °) and the
output of the current swing operation element is
positive (mean=1), then it judges whether the
system will lose synchronism or an unstable
condition will occur. On the other hand, if the
predicted angle is less than the critical angle and the
output of the current swing operation element is
negative (mean =0), then it judges the system to be
stable.
The fault detection technique detects a fault
when the difference in current phasors at both ends
exceeds the threshold value (in this case, 3.4 kA).
This technique can detect current fault magnitude
and current difference rate of change in both steady-
state and power-swing conditions; mutual coupling
and series impedance imbalances have no effect on
its performance. The fault is detected as a current
fluctuation (current rate of change A/ms), and a
current difference starts increasing until reaching the
maximum value (in this case around 10KA) during
the transient fault which is simulated at switching
time start from (0.5sec and clear around 1sec). as
shown in Figure 7.
Table 2. Simulation results for different size of fault
Fig. 7: A fault current magnitude and rate of change
detected
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
359
Volume 18, 2023
The difference in positive sequence current at
both ends before and after transient fault is shown in
Figure 8 and Figure 9 respectively.
Fig. 8: Difference in positive sequence current at
both ends during normal condition.
During the normal condition, as shown in
Figure 8, the current difference at both ends of the
tie lines starts fluctuating during the power system
turn-on until the system reaches a steady-state point
(in this case after 0.1sec). After this point (0.1sec),
the current remains constant (around 34.3 A) as long
as there is no fault in the system.
Fig. 9: Difference in positive sequence current at
both ends during fault condition
As shown in Figure 9, the current difference
starts fluctuating around 9.6 KA and starts
increasing sharply during the transient fault (in this
case, the switching time starts at 0.5sec and clears at
1sec), so the fault current during an abnormal
condition can be detected with high accuracy and a
short detection time by the proposed method.
The phase angle difference of the positive
sequence voltage at both ends during the normal
condition is shown in Figure 10. The phase angle
difference starts fluctuating during the operating
condition, and the angle oscillation begins
decreasing until the system reaches a steady-state
point (in this case, around 0.15 sec). After this point,
the phase angle difference will remain constant
(around 26.6°) as long as the system is in normal
operation.
Fig. 10: Phase angle difference of the positive
sequence voltage at both ends during normal
condition.
When a fault occurs at switching time from 0.5s
to 1sec on a faulted line, the unbalance between load
and generation on the other line causes a power
swing. The relay is prevented from operating if the
oscillations are small and the swing is stable
because the predicted phase angle difference is still
less than the critical value, which in this case is
100°.
On the other hand, if the predicted angle goes
above δ_critical= 100° and the current swing
detection operates, then the unstable power swing is
declared, and the relay must be tripped quickly to
separate the asynchronous area from the overall
system to avoid system collapse.
Figure 11 shows the plot of the phase difference
between the two buses without a proposed
protection scheme during an unstable swing. It is
clear that the phase angle difference begins to
fluctuate and increase during the fault time duration
(from 0.5sec to 1sec) and that after the fault
(1.1sec), the phase angle difference between two
interconnected areas starts to separate above 180°.
The system loses stability around 1.15 sec, and the
system will lose the synchronization.
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
360
Volume 18, 2023
Fig. 11: System without protection scheme.
Figure 12 represents the phase angle difference
plot of the same case with the proposed protection
scheme. The predicted angle passes the critical
value at around 0.97s, and the current swing
detection element detects the current size, causing
the system to be declared unstable and the relay to
trip at around 0.98s. As a result of this method, the
swinging condition can be predicted in advance,
increasing the decision time for the OST function.
Fig. 12: System with proposed protection scheme.
5 Conclusions
This paper presents a new out-of-step detection
method for multi-machine systems using wide-area
measurements based on PMUs. Two schemes are
proposed: one based on positive phase angle
difference calculation between two interconnected
areas at different fault sizes, which evaluates system
condition based on predicted angle, and the other
based on phasor current difference calculation
between interconnected areas, which works as a
second check criteria where both algorithms work
simultaneously. The proposed method can detect
stable and unstable power swings and faults with
high speed and accuracy (around 99%) without
being affected by system parameters.
The angle prediction time is relatively short
(around 20ms), making it compatible with current
swing element operation. To validate the proposed
method, a different fault resistance range (1mΩ up
to 100Ω), and fault time durations (at switching
times of 0.5sec and clear at 1sec) were created in the
system to evaluate the accuracy of the phase angle
prediction scheme with current swing detection
elements during stable and unstable power swings
using MATLAB/Simulink software.
Nomenclature:
δp = Predicted relative phase angle difference
δα, δβ = phase angles difference measured values at
different time
, , = difference in the phase angle of
the first samples
, , = difference in the phase angle of
the second samples
λ, μ = ratio of phase angle difference
= maximum value of the positive sequence
current
= minimum value of the positive sequence
current
= time period that is determined by the
simulation
N = constant number that is used as a comparator
with a current rate of change
= setting current that is determined by the
simulation
= current rate of change
References"
[1] P. Kundur, "Power Stability and Control," The
EPRI Power System Engineering Series, New
York: McGraw Hill Inc., 2004.
[2] B. Patel, "A new technique for detection and
classification of faults during power swing,"
Electric Power Systems Research, vol.175,
p.105920,2019/10/01/2019.
[3] R. Emami and A. Abur, " External system line
outage identification usihg phasor
measurement units" IEEE Transactions on
Power Systems, Vol.28, No. 2, 2013, pp.
1035-1040.
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
361
Volume 18, 2023
[4] A. Haddadi, I. Kocar, U. Karaagac, H. Gras,
and E. Farantatos, "Impact of Wind
Generation on Power Swing Protection," IEEE
Transactions on Power Delivery, vol. 34, no.
3, pp. 1118-1128, 2019, doi:
10.1109/TPWRD.2019.2896135.
[5] K. Tuttelberg, M. Loper and J. Kilter,
"Correcting Systematic Errors in Corona
Losses Measured with Phasor Measurement
Units", IEEE Transactions on Power Delivery,
Vol.34, No.6, 2019, pp. 2275-2277.
[6] S. Kumer, B. Tyagi, V.Kumer and S. Chohan,
"Optimization of Phasor Measurement Units
Placement Under Contingency Using
Reliability of Network Components" IEEE
Transactions on Instrumentation and
Measurement, Vol.69, No.12, 2020, pp9893-
9906
[7] X. Wang, D.Shi, Z. Wang, C. Xu, Q. Zhang,
X. Zhang and Z. Yu, "Online Calibration of
Phasor Measurement Unit Using Density-
Based Spatial Clustering", IEEE Transactions
on Power Delivery, Vl.33, No.3, pp. 1081-
1090
[8] D. Georgakopoulos and S. Quigg, "Precision
Measurement System for the Calibration of
Phasor Measurement Units", IEEE
Transactions on Instrumentation and
Measurement, Vol.66, No.6, 2017, pp.1441-
1445
[9] F. A. Gorjayi and H. M. Rad, " Aphysics-
Aware MIQP Approach to Harmonic State
Estimation in Low-Observable Power
Distribution Systems Using Harmonic Phasor
Measurement Units" IEEE Transactions on
Smart Gride, Vol.14, No.3, 2023, pp. 2111-
2114
[10] A. Xue, F. Xu, J. Xu, J. H.Chow, H. You and
T. Bi, "Correction of Phasor Measurement
Independent of Transmission Line
Parameters", IEEE Transactions on Smart
Grid, Vol.11, No.1, 2020, pp. 346-356.
[11] A. A. Elsayed and M. A. Mohamed, "Optimal
Micro-PMU Placement Based on Hybrid
Current Channels Selection for Distribution
Grids", IEEE Transactions on Industry
Applications, Vol.56, No.6, pp. 6871-6881
[12] I. Ivanković, D. Brnobić, R. Rubeša and M.
Rekić, "Line Differential Protection with
Synchrophasor Data in WAMPAC System in
Control Room," 2020 3rd International
Colloquium on Intelligent Grid Metrology
(SMAGRIMET), Cavtat, Croatia, 2020, pp. 72-
78, doi:
10.23919/SMAGRIMET48809.2020.9264020.
[13] H. D. Al-Majali and S. Al-Dhalaan, “A
Snubber Configuration for Modified Bridge
Converter” Electric Power Components and
Systems (Taylor & Francis), Vol.34, No.11,
2006, PP. 1177-1190.
[14] D. M. Timofeev and T. G. Klimova, "Analysis
of Possibility of Using Pmu Based Methods
for Providing the Correct Operation of
Distance Protection," 2018 International
Youth Scientific and Technical Conference
Relay Protection and Automation (RPA),
Moscow, Russia, 2018, pp. 1-14, doi:
10.1109/RPA.2018.8537231.
[15] I. Višić, I. Strnad and T. Tonković, "Real
Time Load Angle Application for
Synchronous Generator Protection Purposes,"
2019 2nd International Colloquium on Smart
Grid Metrology (SMAGRIMET), Split,
Croatia, 2019, pp.1-5.
[16] P. Kundu, J. Ganeswara Rao, P. K. Nayak and
A. K. Pradhan, "Wide area measurement based
out-of-step detection technique," 2010 Joint
International Conference on Power
Electronics, Drives and Energy Systems &
2010 Power, India, New Delhi, India, 2010,
pp. 1-5, doi: 10.1109/PEDES.2010.5712569.
[17] "IEEE/IEC International Standard - Measuring
relays and protection equipment - Part 118-1:
Synchrophasor for power systems -
Measurements," in IEC/IEEE 60255-118-
1:2018, vol., no., pp.1-78, 19 Dec. 2018, doi:
10.1109/IEEESTD.2018.8577045.
[18] G. Lee, S. H. Kim and Y. -J. Shin, "Time-
Synchronized Measurements and Applications
for Monitoring of Intelligent Electric Power
Systems," 2018 IEEE International
Conference on Big Data and Smart
Computing (BigComp), Shanghai, China,
2018, pp. 751-755, doi:
10.1109/BigComp.2018.00143.
[19] “Power Swing and Out-of-Step Considerations
on Transmission Lines”, IEEE PSRC WG D6,
A report to the Power System Relaying
Committee OF the IEEE Power Engineering
Society, 2005, [Online].
https://www.ewh.ieee.org/r6/san_francisco/pes
/pes_pdf/OutOfStep/PowerSwingOOS.pdf
(Accessed Date: January 11, 2024).
[20] Y.-J. Lee, O.-S. Kwon, J.-Y. Heo, and C.-H.
Kim, “A Study on the Out-of-Step Detection
Algorithm Using Time Variation of Complex
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
362
Volume 18, 2023
Power-Part II: Out-of-Step Detection
Algorithm and Simulation Results,” Energies,
vol. 13, no. 7, p. 1833, Apr. 2020, doi:
10.3390/en13071833.
[21] Y. Hamid, “An adaptive impedance-based out-
of-step detection of synchronous generator
without any network reduction,” IET
Generation, Transmission & Distribution, vol.
14, Mar. 2020, doi: 10.1049/iet-
gtd.2019.0850.
[22] Y. Ma, Q. Huang, Z. Zhang and D. Cai, "
Application of Multi-synchrosqueezing
Transform for Sub synchronous Oscillation
Detection Using PMU Data", IEEE
Transactions on Industry Applications,
Vol.57, No.3, 2021, pp. 2006-2013.
[23] V. A. Ambekar and S. S. Dambhare,
"Comparative evaluation of out of step
detection schemes for distance relays," 2012
IEEE Fifth Power, India Conference, Murthal,
India, 2012, pp. 1-6, doi:
10.1109/PowerI.2012.6479500.
[24] N. Fischer, G. Benmouyal, D. Hou, D.
Tziouvaras, J. Byrne-Finley, and B. Smyth,
“Tutorial on power swing blocking and out-of-
step tripping,” in Proc. 39th Annu. Western
Protective Relay Conf., Spokane, WA, USA,
Oct. 2012.
[25] Q. Verzosa, "Realistic testing of power swing
blocking and out-of-step tripping functions,"
2013 66th Annual Conference for Protective
Relay Engineers, College Station, TX, USA,
2013, pp. 420-449, doi:
10.1109/CPRE.2013.6822056.
[26] H. D. Al-Majali, “Abnormal Harmonics
Generated by Modified HVDC Converters”
Electric Power Components and Systems
(Taylor & Francis), Vol.35, No.6, 2006, PP
639 – 654.
[27] N/ M. Manousakis and G. N. Korres, "Optimal
Allocation of Phasor Measurement Units
Considering Various Contingencies and
Measurement Redundancy", IEEE
Transactions on Instrumentation and
Measurement, Vol.69, No.6, 2020, pp.3403-
3411.
[28] H. D. Al-Majali, B. H. Al-Majali and Z. S.
Almajali ," Reduced Harmonics Generated
and Reactive Volt-Ampere absorption of
HVDC Converter Using By-Pass Switch",
WSEAS Transaction on Control and Systems,
Vol.15, pp 218 -227, 2020,
https://doi.org/10.37394/23203.2020.15.23.
[29] P. Briff, J. C. Zabalza, J. Nicholls and K.
Vershinin, "Turn-Off Delay Compensations of
Series-Connected IGBTs for HVDC
Applications", IEEE Transactions on Power
Electronics, Vol.35, No.11, 2020, pp. 11294-
11298.
[30] H. D. Al-Majali and B. H. Al-Majali, "Fast
and Continuous Control of a Modified HVDC
Converter", WSEAS Transaction on Control
and Systems, Vol.19, PP.326-332, 2019.
Contribution of Individual Authors to the
Creation of a Scientific Article (Ghostwriting
Policy)
The authors equally contributed in the present
research, at all stages from the formulation of the
problem to the final findings and solution.
Sources of Funding for Research Presented in a
Scientific Article or Scientific Article Itself
No funding was received for conducting this study.
Conflict of Interest
The authors have no conflicts of interest to declare.
Creative Commons Attribution License 4.0
(Attribution 4.0 International, CC BY 4.0)
This article is published under the terms of the
Creative Commons Attribution License 4.0
https://creativecommons.org/licenses/by/4.0/deed.en
_US
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.36
Zaid S. Al-Shamaain, Hussein. D. Al-Majali, Bilal. H. Al-Majali
E-ISSN: 2224-350X
363
Volume 18, 2023