Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study
Integration of interconnected power system (IPS) of Ukraine to the European Network Transmission System Operators for Electricity (ENTSO-E) requires an improvement of Ukrainian frequency automatic emergency control and harmonization with load-frequency control according to requirements of ENTSO-E. I...
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Інститут електродинаміки НАН України
2017
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irk-123456789-1588832019-09-16T01:25:50Z Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study Kyrylenko, O.V. Pavlovsky, V.V. Steliuk, А.О. Lenga, O.V. Vyshnevskyi, M.V. Електроенергетичні системи та устаткування Integration of interconnected power system (IPS) of Ukraine to the European Network Transmission System Operators for Electricity (ENTSO-E) requires an improvement of Ukrainian frequency automatic emergency control and harmonization with load-frequency control according to requirements of ENTSO-E. In order to investigate processes of frequency and active power control, it is necessary to develop the detailed simulation model including models of automatic under frequency load shedding (UFLS) relays, special protection automatics (SPA) of the nuclear power plants, automatic generation control (AGC) as well as 750-220 kV transmission networks of IPS of Ukraine. The frequency stability phenomena have been studied by time domain simulation using the detailed model realized in DIgSILENT PowerFactory software. The simulation results for different disturbances are presented. Підключення об’єднаної енергетичної системи (ОЕС) України на паралельну роботу з енергооб’єднанням ENTSO-E потребує удосконалення протиаварійного керування та гармонізації вимог щодо автоматичного регулювання частоти та потужності відповідно до тих, що діють в ENTSO-E. Для дослідження процесів зміни частоти та активної потужності необхідно розробити деталізовану модель, яка містить пристрої автоматичного частотного розвантаження, частотну автоматику енергоблоків атомних електростанцій, систему автоматичного регулювання частоти та потужності, а також магістральні мережі 750-220 кВ ОЕС України. Досліджено стійкість за частотою шляхом моделювання електромеханічних перехідних процесів з використанням програмного забезпечення DIg-SILENT PowerFactory. Наведено результати досліджень для виникнення різних збурень. Подключение объединённой энергетической системы (ОЭС) Украины на параллельную работу с энергообъединением ENTSO-E требует усовершенствования противоаварийного управления и гармонизации требований в части автоматического регулирования частоты и мощности в соответствии с действующими в ENTSO-E. Для исследования процессов регулирования частоты и активной мощности необходимо разработать детализированную модель, учитывающую устройства автоматической частотной разгрузки, частотную автоматику энергоблоков атомных электростанций, систему автоматического регулирования частоты и мощности, а также магистральные сети 750-220 кВ ОЭС Украины. Исследована устойчивость по частоте путем моделирования электромеханических переходных процессов с использованием программного обеспечения DIgSILENT PowerFactory. Приведены результаты исследований в случае возникновения различных возмущений. 2017 Article Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study / O.V. Kyrylenko, V.V. Pavlovsky, А.О. Steliuk, O.V. Lenga, M.V. Vyshnevskyi // Технічна електродинаміка. — 2017. — № 2. — С. 57-60. — Бібліогр.: 12 назв. — англ. 1607-7970 DOI: https://doi.org/10.15407/techned2017.02.057 http://dspace.nbuv.gov.ua/handle/123456789/158883 621.311:681.3 en Технічна електродинаміка Інститут електродинаміки НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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DSpace DC |
| language |
English |
| topic |
Електроенергетичні системи та устаткування Електроенергетичні системи та устаткування |
| spellingShingle |
Електроенергетичні системи та устаткування Електроенергетичні системи та устаткування Kyrylenko, O.V. Pavlovsky, V.V. Steliuk, А.О. Lenga, O.V. Vyshnevskyi, M.V. Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study Технічна електродинаміка |
| description |
Integration of interconnected power system (IPS) of Ukraine to the European Network Transmission System Operators for Electricity (ENTSO-E) requires an improvement of Ukrainian frequency automatic emergency control and harmonization with load-frequency control according to requirements of ENTSO-E. In order to investigate processes of frequency and active power control, it is necessary to develop the detailed simulation model including models of automatic under frequency load shedding (UFLS) relays, special protection automatics (SPA) of the nuclear power plants, automatic generation control (AGC) as well as 750-220 kV transmission networks of IPS of Ukraine. The frequency stability phenomena have been studied by time domain simulation using the detailed model realized in DIgSILENT PowerFactory software. The simulation results for different disturbances are presented. |
| format |
Article |
| author |
Kyrylenko, O.V. Pavlovsky, V.V. Steliuk, А.О. Lenga, O.V. Vyshnevskyi, M.V. |
| author_facet |
Kyrylenko, O.V. Pavlovsky, V.V. Steliuk, А.О. Lenga, O.V. Vyshnevskyi, M.V. |
| author_sort |
Kyrylenko, O.V. |
| title |
Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study |
| title_short |
Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study |
| title_full |
Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study |
| title_fullStr |
Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study |
| title_full_unstemmed |
Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study |
| title_sort |
simulation of the normal and emergency operation of interconnected power system of ukraine for frequency stability study |
| publisher |
Інститут електродинаміки НАН України |
| publishDate |
2017 |
| topic_facet |
Електроенергетичні системи та устаткування |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/158883 |
| citation_txt |
Simulation of the normal and emergency operation of interconnected power system of Ukraine for frequency stability study / O.V. Kyrylenko, V.V. Pavlovsky, А.О. Steliuk, O.V. Lenga, M.V. Vyshnevskyi // Технічна електродинаміка. — 2017. — № 2. — С. 57-60. — Бібліогр.: 12 назв. — англ. |
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Технічна електродинаміка |
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ISSN 1607-7970. Техн. електродинаміка. 2017. № 2 57
ЕЛЕКТРОЕНЕРГЕТИЧНІ СИСТЕМИ ТА УСТАНОВКИ
SIMULATION OF THE NORMAL AND EMERGENCY OPERATION OF INTERCONNECTED
POWER SYSTEM OF UKRAINE FOR FREQUENCY STABILITY STUDY
O.V. Kyrylenko1, V.V. Pavlovsky1, А.О. Steliuk1, O.V. Lenga1, M.V. Vyshnevskyi2
1 - Institute of Electrodynamics, National Academy of Sciences of Ukraine,
pr. Peremohy, 56, Kyiv, 03057, Ukraine, e-mail: astelyuk@gmail.com
2 - National power company “Ukrenergo”,
S. Petliury str., 25, Kyiv, 01032, Ukraine.
Integration of interconnected power system (IPS) of Ukraine to the European Network Transmission System Operators
for Electricity (ENTSO-E) requires an improvement of Ukrainian frequency automatic emergency control and harmoni-
zation with load-frequency control according to requirements of ENTSO-E. In order to investigate processes of fre-
quency and active power control, it is necessary to develop the detailed simulation model including models of automatic
under frequency load shedding (UFLS) relays, special protection automatics (SPA) of the nuclear power plants, auto-
matic generation control (AGC) as well as 750-220 kV transmission networks of IPS of Ukraine. The frequency stability
phenomena have been studied by time domain simulation using the detailed model realized in DIgSILENT PowerFac-
tory software. The simulation results for different disturbances are presented. References 12, figures 5.
Key words: frequency stability, automatic under frequency load shedding, special protection automatics, power flow,
primary and secondary control, automatic generation control, interconnected power system.
One of the state priorities of Ukraine is an integration of the national IPS to ENTSO-E grid. Imple-
menting this strategy requires solution of the numerous of tasks. Among others, it’s necessary to improve
power system dispatch (considering an increasing of the stochastic generating power of the renewables),
voltage and reactive power control, power quality etc. The most important task is an improvement of fre-
quency emergency automatics and load-frequency control [1, 2]. This paper is devoted to frequency stability
simulation in IPS of Ukraine. Performing this study requires a development of the detailed models consider-
ing an operation UFLS relays, special frequency protection automatics (SPA), which are used in the island-
ing schemes of Ukrainian nuclear power plants, and national AGC, and detailed model of 750-220 kV
transmission networks. In order to simulate UFLS and AGC operation, a lot of approaches have been utilized
[3-10]. In [3], various automatic load shedding strategies are investigated to provide frequency stability in
ENTSO-E using simplified system models. In [4, 5], the effect of the automatic loading shedding on fre-
quency stability has been analyzed in case of blackout and islanding of the power system. The simulation
results are provided by using an example of equivalent model that does not allow to estimate proposed solu-
tions for a real scale power system. In [9, 10] load-frequency control is investigated using a model, which is
presented by the equivalent elements. In this paper, the detailed model of IPS of Ukraine has been developed
including models of UFLS relays, SPA and AGC. Using of the abovementioned model allows to study fre-
quency stability in more detail and with consideration of the loading of interfaces in of IPS of Ukraine. Be-
sides, this advanced software model is capable to be used to simulate these processes in case of wind and
solar power plants’ participation in frequency control. This is very important toolbox to detail study of fre-
quency stability of IPS of Ukraine with consideration of future integration to ENTSO-e system.
At present time, IPS of Ukraine is divided into five separately operated zones. The main part of the
Ukrainian power system operates synchronously with IPS/UPS (Russia, Belarus and Moldova). The maximal
demand of this zone is about 23100 MW. The second zone is Burshtyn island, operating synchronously with
ENTSO-E. It is separated from the main part of the Ukrainian power system. The third zone is presented by
small part of the Ukrainian power system in the east, which is energized from Russian unified power system
(UPS). The maximal load of this zone is approximately 500 MW. The fourth and fifth zones are presented by
the island of Luhanska thermal power plant (the fourth zone, its maximal load is about 400 MW) and the
island of Zuyivska/Staribeshivska thermal power plants, which maximum load is 1318 MW.
In order to preserve a frequency stability of IPS of Ukraine in case of severe disturbances, UFLS re-
lays are used. Depending on the frequency and operation time settings, there are following categories of
UFLS:
© Kyrylenko O.V., Pavlovsky V.V., Steliuk А.О., Lenga O.V., Vyshnevskyi M.V., 2017
58 ISSN 1607-7970. Техн. електродинаміка. 2017. № 2
1) special UFLS used to prevent a frequency decreasing to operation settings of UFLS-2. Frequency
pick-up setting is 49.2 Hz, pick up time is 0.3-0.5 s.
2) protective UFLS, used in order to prevent operation of SPA which isolate of the nuclear plants to is-
land operation in case of a dangerous frequency decreasing (less than 49 Hz) in the system. Fre-
quency pick up of this UFLS is 49.1 Hz, pick up time is 0.3-0.5 s.
3) UFLS-1 (the first category) used to prevent a frequency decreasing. This category of high-speed de-
vices UFLS has different frequency setting in order to adapt to various disturbances in IPS of
Ukraine (or its isolated parts) and to eliminate a frequency decreasing. Frequency pick up settings
are in the range 48,8-47,2 Hz; pick up time 0.3-0.5 s.
4) UFLS-2n – not combined UFLS-2 (the second category). This is slow category that is not combined
with UFLS-1, and must to increase frequency after UFLS-1 picked up when frequency decreases at
unacceptably low level. Frequency pick up setting is 49.1 Hz and time pick up settings are in the
range from 5 to 20 sec with intervals 3 sec.
5) UFLS-2c - combined UFLS-2 (the second category), which must to eliminate frequency decrease
with relatively slow power deficit increase (frequency drift), and to increase the frequency in the
case UFLS-2n inefficient operation. Frequency pick up settings are in the range from 48.7 Hz to 49
Hz; time pick up settings are in the range 21 s to 60 s.
Besides, in order to ensure the safe operation of nuclear power plants, SPA relays are also used.
These devices are configured in such a way, that even short-term reduction of frequency below 46
Hz was quite avoidance. The SPA operation time with frequency lower than 47 Hz is less than 10
seconds; lower than 48 Hz – not exceeding 1 min and lower than 49 Hz – less than 5 minutes.
The simplified structure of AGC organization in IPS of Ukraine considering its main part is pre-
sented in Fig. 1.
In UPS of Russia, the hierarchical structure of AGC is used. The coordinated AGC system of the up-
per level controls the frequency in interconnected power system
of Russia with other Commonwealth of Independent States
countries by generating a control signal ΔPrefRU. In European
part of Russia, the frequency is controlled by Volga hydroelec-
tric power station (HPS) while in IPS of Belarus the frequency
is controlled by dispatcher. In IPS of Ukraine, Dneprovskaya
HPS-1 participates in the secondary control only.
The input signals of the national AGC are the frequency
in IPS of Ukraine f and tie line interchanges Ptie-line with UPS
of Russia and IPS of Belarus. The national AGC regulates the
net interchange power and the frequency. Based on these meas-
ured signals the proportional integral (PI) controller generates
the control signal ΔPrefUA to the regulating units of Dne-
provskaya HPP-1. Further, at power plant control level, this
signal is distributed among regulating units of Dneprovskaya
HPP-1. At aggregate control level, the turbine governor gener-
ates a signal of the turbine power change [11, 12].
Some simulation results for UFLS relay
operation in case of two 1000 MW generating
units disconnection (isolated operation of IPS of
Ukraine) is presented in Fig. 2 and Fig. 3.
As seen in Fig. 3, up to 20 sec. after dis-
turbances a consumption is decreasing due to
frequency drop (self-regulation effect). In case of
the frequency decreasing to UFLS relay setting,
the load is reduced by UFLS operation. The total
load reduction is 190 MW at this substation.
Simulation results of AGC operation in
case of generating unit disconnection of the ther-
UPS of Russia
AGC
f
Volga HPS
ΔPref
RU
IPS of Ukraine
SCADA-
AGC
f
Dneprovskaya HPS
Power
controller
Ptie-line
ΔPref
UA
IPS of Belarus
Governor Governor
G-1 G-6
Control level
System
Station
Aggregate
IPS of Ukraine-
IPS of Belarus
interface
IPS of Ukraine-
UPS of Russia
interface
Fig. 1 50,3
49,8
49,3
48,8
48,3
47,8
Y = 49,00 Hz
Y = 48,00 Hz
50 Hz
50403020100 t, sec
f,
H
z
Fig. 2
ISSN 1607-7970. Техн. електродинаміка. 2017. № 2 59
mal power plant (parallel operation of IPS of Ukraine) are presented in Fig. 4-6. The participation factors of
the generating units of Dneprovskaya HPS-1 in the
secondary frequency control are equal to 0.2; 0.14;
0.2; 0.16; 0.18 and 0.12 pu.
As seen in Fig. 4, the generator loss is fully
compensated by the power change of the generating
units Dneprovskaya HPP-1 according to their par-
ticipation factors in the secondary frequency control.
After secondary frequency control, the net inter-
change power at the interface between power sys-
tems of Ukraine and Russia is also restored at its
scheduled value as well (Fig. 5).
It should be noted, that the simulation of the load-frequency control has been performed considering
the normal operation of IPS/UPS. At the same time, identifying of the critical loading of overhead lines in
emergency operation of the power system will allow to define these overloadings to prevent their possible
disconnection.
The presented simulation results demonstrate an operation of the proposed UFLS, SPA and AGC
models of IPS of Ukraine after different disturbances. The developed advances software model is realized in
DIgSILENT PowerFactory software.
The model is used to investigate all aspects frequency stability (inertial system response, primary ac-
tive power control, UFLS and SPA operation, secondary control in IPS of Ukraine) for various scenarios of
power imbalances.
1. Alekseev S., Kopylov I., Mashanskii A. Interconnected power utilities description as object of frequency and
active power control // Elektrichestvo. – 1980. – No 12. – Pp. 23-30. (Rus)
2. Kyrylenko O., Pavlovsky V., Steliuk A. AGC Software Model Validation for Identification of Renewables
Impact on Frequency Control in the IPS of Ukraine / Proceedings of International Conference on Intelligent
Energy and Power Systems. – Kyiv, June 2014. – Pp. 141-145.
3. Pavlovsky V., Steliuk A., Lenga O., Zaychenko V., Vyshnevskyi M., Antoniuk Ya. Influence of the frequency and
voltage change on load power considering automatic frequency load shedding // Enerhetyka i Elektryfikatsiia.
– 2016. – No 4. – Pp. 7-12. (Ukr)
4. Diviya K.C., Nagendra Rao. A novel AGC simulation scheme based on reduced order prime mover models /
Conference on Convergent Technologies for the Asia-Pacific Region. – 2003. – Vol. 3. – Pp. 1099-1103.
5. Gonzalez-Longatt F., Steliuk A., Hinojosa V.H. Flexible Automatic Generation Control System for Embedded
HVDC Links // Proceedings of IEEE PowerTech conference. – Eindhoven, June 2015.
6. Gonzalez-Longatt, Francisco, Luis Rueda, Jose. PowerFactory Applications for Power System Analysis. –
Springer, 2015. – 489 p.
7. Hsu C.-T., Kang M.-S., Chen C.-S. Design of adaptive load shedding by artificial neural networks // IEE Proc.
Gener. Transm. Distrib. – 2005. – Vol. 152. – No 3. – Pp. 415-421.
50403020100 t, sec
290
240
190
140
90
40
251.5 MW
213 MW
160.6 MW
120 MW
101 MW
92 MW
61.3 MW
Р
, M
W
Fig. 3
Fig. 4 Fig. 5
60 ISSN 1607-7970. Техн. електродинаміка. 2017. № 2
8. Nanda J., Mishra S., Mishra P. and Sajith K. A novel classical controller for automatic generation control in
thermal and hydrothermal system / Joint International Conference on Power Electronics, Drives and Energy
Systems, India. – 2010. – Pp. 1-6.
9. Ramavathu S.N., Datla V.T., Pasagadi H. Islanding Scheme and Auto Load Shedding to Protect Power System
// International Journal of Computer and Electrical Engineering. – 2013. – Vol. 1. – No 4. – Pp. 508-512.
10. Shahgholian G., Salary M.E. Effect of Load Shedding Strategy on Interconnected Power Systems Stability
When a Blackout Occurs // International Journal of Computer and Electrical Engineering. – 2012. – Vol. 4. –
No 2. – Pp. 212-217.
11. Talaq J., Al-Basri F. Adaptive fuzzy gain scheduling for load frequency control // IEEE Trans. on Power
Systems. – 1999. – Vol. 14. – No 1. – Pp. 145-150.
12. Technical Background for the Low Frequency Demand Disconnection Requirements. Available at:
https://www.entsoe.eu/Documents/Network%20codes%20documents/NC%20ER/141215_Technical_backgrou
nd_for_LFDD.pdf. – 2014. – 20 p. (accessed 24.11.2016)
УДК 621.311:681.3
МОДЕЛЮВАННЯ НОРМАЛЬНИХ ТА АВАРІЙНИХ РЕЖИМІВ ОБ'ЄДНАНОЇ ЕНЕГОСИСТЕМИ
УКРАЇНИ ДЛЯ ДОСЛІДЖЕННЯ СТІЙКОСТІ ЗА ЧАСТОТОЮ
О.В. Кириленко1, академік НАН України, В.В. Павловський1, докт.техн.наук, А.О. Стелюк1, канд.техн.наук,
О.В. Леньга1, М.В. Вишневський2
1 - Інститут електродинаміки НАН України, пр. Перемоги, 56, Київ, 03057, Україна,
2 - Державне підприємство «Національна енергетична компанія «Укренерго»,
вул. С. Петлюри, 25, Київ, 01032, Україна. e-mail: astelyuk@gmail.com
Підключення об’єднаної енергетичної системи (ОЕС) України на паралельну роботу з енергооб’єднанням
ENTSO-E потребує удосконалення протиаварійного керування та гармонізації вимог щодо автоматичного
регулювання частоти та потужності відповідно до тих, що діють в ENTSO-E. Для дослідження процесів змі-
ни частоти та активної потужності необхідно розробити деталізовану модель, яка містить пристрої авто-
матичного частотного розвантаження, частотну автоматику енергоблоків атомних електростанцій, сис-
тему автоматичного регулювання частоти та потужності, а також магістральні мережі 750-220 кВ ОЕС
України. Досліджено стійкість за частотою шляхом моделювання електромеханічних перехідних процесів з
використанням програмного забезпечення DIg-SILENT PowerFactory. Наведено результати досліджень для
виникнення різних збурень. Бібл. 12, рис. 5.
Ключові слова: стійкість за частотою, автоматичне частотне розвантаження, частотна автоматика, перетік по-
тужності, первинне та вторинне регулювання, система автоматичного регулювання частоти та потужності,
об’єднана енергосистема.
УДК 621.311:681.3
МОДЕЛИРОВАНИЕ НОРМАЛЬНЫХ И АВАРИЙНЫХ РЕЖИМОВ ОБЪЕДИНЕННОЙ
ЭНЕРГОСИСТЕМЫ УКРАИНЫ ДЛЯ ИССЛЕДОВАНИЯ УСТОЙЧИВОСТИ ПО ЧАСТОТЕ
А.В. Кириленко1, академик НАН Украины, В.В. Павловский1, докт.техн.наук, А.О. Стелюк1, канд.техн.наук,
О.В. Леньга1, Н.В. Вишневский2
1 - Институт электродинамики НАН Украины, пр. Победы, 56, Киев, 03057, Украина,
2 - Государственное предприятие «Национальная энергетическая компания «Укрэнерго»,
ул. С. Петлюры, 25, Киев, 01032, Украина. e-mail: astelyuk@gmail.com
Подключение объединённой энергетической системы (ОЭС) Украины на параллельную работу с энергообъеди-
нением ENTSO-E требует усовершенствования противоаварийного управления и гармонизации требований в
части автоматического регулирования частоты и мощности в соответствии с действующими в ENTSO-E.
Для исследования процессов регулирования частоты и активной мощности необходимо разработать детали-
зированную модель, учитывающую устройства автоматической частотной разгрузки, частотную автома-
тику энергоблоков атомных электростанций, систему автоматического регулирования частоты и мощно-
сти, а также магистральные сети 750-220 кВ ОЭС Украины. Исследована устойчивость по частоте путем
моделирования электромеханических переходных процессов с использованием программного обеспечения
DIgSILENT PowerFactory. Приведены результаты исследований в случае возникновения различных возмущений.
Библ. 12, рис. 5.
Ключевые слова: устойчивость по частоте, автоматическая частотная разгрузка, частотная автоматика, переток
мощности, первичное и вторичное регулирование, система автоматического регулирования частоты и мощнос-
ти, объединенная энергосистема.
Надійшла 30.11.2016
Остаточний варіант 02.12.2016
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