IEEE Power & Energy Magazine - July/August 2019 - 34

with ac facilities and the interrupt capacity of the CBs in the
metropolitan area would need to be increased. The replacement of CBs is challenging due to cost considerations and
insufficient installation space at existing substations. In addition, it is difficult to replace several CBs at the same time,
which may also interfere with existing system protection coordination. HVdc applications reduce the short circuit capacity
and control both the active and reactive power (especially
using voltage source converters) that improves the stability
and security performance of the entire power system.
Controlling power flow in an ac power system is difficult,
but it is easily achievable in a dc system. Power electronicsbased substations can be called smart substations. HVdc
and FACTS equipment, which has high control bandwidth,
can provide grid services, such as voltage regulation, black
start, special protection schemes (SPSs), virtual inertia support, and primary and secondary frequency regulation. For
example, this type of substation might prevent a blackout
through coordinated control using SPSs. A sudden power
transfer increase achieved through an SPS is a key requirement of the east-metropolitan interconnection HVdc project
that reduces the number of required generator trips upon
occurrence of a key N - 1 contingency (a fault on an existing 765-kV transmission line). The controllability of power
electronics-based substations increases the efficiency and
reliability of the overall power system and plays a key role in
the future power system.

The Vision for the Future Smart and
Green Substations and the Smart Grid
A smart and green power grid may be defined as efficient,
reliable, flexible, and resilient with a high integration of
DERs; these smart and green substations will be crucial in
addressing the challenges presented by future changes to the
power system. The functionalities and benefits of smart and
green substations are as follows:
✔ easier implementation, installation, maintenance, and
upgrades, e.g., a modular substation
✔ real-time data acquisition and analysis, e.g., online
load modeling, behind-the-meter forecasting, and active
network management
✔ smart control and protection, e.g., fast SPS using
HVdc, a modular substation with an ESS, substations
with FACTSs, and self-healing (automatic substation
restoration system)
✔ enhancing the efficiency of the entire power grid, e.g.,
power flow control of HVdc and optimal grid planning and grid operation
✔ an ecofriendly design and construction, e.g., SF6-gasfree substations.

Acknowledgments
This work was supported by the Korea Electric Power
Corporation (grant R17XA05-4). This work was also
supported by the "Human Resources Program in Energy
34

ieee power & energy magazine

Technology" of the Korea Institute of Energy Technology
Evaluation and Planning, granted financial resource from
the Ministry of Trade, Industry & Energy, the Republic of
Korea (20194030202420).

For Further Reading
Korea Electric Power Statistics Information System. Accessed
on: May 3, 2019. [Online]. Available: http://epsis.kpx.or
.kr/epsisnew/selectEkesKepChart.do?menuId=010100&
locale=eng
S. Kim et al., "Improvement in policy and proactive interconnection procedure for renewable energy expansion in
South Korea," Renewable Sustainable Energy Rev., vol. 98,
pp. 150-162, Dec. 2018.
"Modular Substation Market by Application (Power Utilities, Commercial, Industrial), Voltage, Type (Trailer Mounted & Fixed), Insulation (Air-Insulated & Gas-Insulated), &
by Region-Global Trends and Forecast to 2020," MarketsandMarkets, Pune, India, 2015. [Online]. Available: https://
www.marketsandmarkets.com/Market-Reports/modularsubstation-market-403992.html
J. D. McDonald, "Substations," in Electric Power Engineering Handbook. Boca Raton, FL: CRC, 2012, ch. 5.
[Online]. Available: http://www.pce-fet.com/common/
library/books/78/2784_ElectricPowerSubstationsEngineer
ing.pdf
J. D. McDonald, "Substation automation: IED integration
and availability of information," IEEE Power Energy Mag.,
vol. 1, no. 2, pp. 22-31, Mar./Apr. 2003
S. Kim et al., "Expanding power systems in the Republic of Korea," IEEE Power Energy Mag., vol. 17, no. 3,
pp. 61-72, May/June 2019.
P. Mohapatra, F. Ainslie, and C. McTaggart, "FITNESS-
Future intelligent transmission network substation," PACworld, Dec. 2016. [Online]. Available: http://www.pacw.org/
issue/december_2016_issue/fitness/fitness_future_intelligent_
transmission_network_substation.html

Biographies
Heejin Kim is with Yonsei University, Seoul, Republic of Korea.
Jae-Kyeong Kim is with Korea Electrotechnology Research Institute, Uiwang, Gyeonggi-do, Republic of Korea.
Jiyoung Song is with KEPCO Research Institute, Daejeon, Republic of Korea.
Jaegul Lee is with KEPCO Research Institute, Daejeon,
Republic of Korea.
Kisun Han is with KEPCO Research Institute, Daejeon,
Republic of Korea.
Jeonghoon Shin is with KEPCO Research Institute,
Daejeon, Republic of Korea.
Taekyun Kim is with KEPCO Research Institute, Daejeon, Republic of Korea.
Kyeon Hur is with Yonsei University, Seoul, Republic of Korea.
p&e
july/august 2019

http://epsis.kpx.or.kr/epsisnew/selectEkesKepChart.do?menuId=010100&locale=eng http://epsis.kpx.or.kr/epsisnew/selectEkesKepChart.do?menuId=010100&locale=eng http://epsis.kpx.or.kr/epsisnew/selectEkesKepChart.do?menuId=010100&locale=eng https://www.marketsandmarkets.com/Market-Reports/modular-substation-market-403992.html https://www.marketsandmarkets.com/Market-Reports/modular-substation-market-403992.html https://www.marketsandmarkets.com/Market-Reports/modular-substation-market-403992.html http://www.pce-fet.com/common/library/books/78/2784_ElectricPowerSubstationsEngineering.pdf http://www.pce-fet.com/common/library/books/78/2784_ElectricPowerSubstationsEngineering.pdf http://www.pce-fet.com/common/library/books/78/2784_ElectricPowerSubstationsEngineering.pdf http://www.pacw.org/issue/december_2016_issue/fitness/fitness_future_intelligent_transmission_network_substation.html http://www.pacw.org/issue/december_2016_issue/fitness/fitness_future_intelligent_transmission_network_substation.html http://www.pacw.org/issue/december_2016_issue/fitness/fitness_future_intelligent_transmission_network_substation.html

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