The New Adaptive Under Frequency Load Shedding Technique in an Automated Distribution Network Considering Demand Response Programs

Amin Mokari-Bolhasan, Navid Taghizadegan-Kalantari


Under Frequency Load Shedding (UFLS) is an important protection scheme to maintain the frequency of a Distribution Network
(DN) consisting of Distributed Generations (DGs) exposed to power deficit. The different location and amount of load
curtailments based on different parameters are acquired from the available literature. In this paper, an optimal adaptive UFLS
method with the advent of two main modules has been proposed. The proposed method provides a revised Rate of Change
of Load (ROCOFL) index related to bus voltage and load power consumption (ROCOFLpv). Using a wide area measurement
system, Demand Response (DR) technology aimed at shedding fewer loads is emerging against a background of the smart
grid. In addition, smart appliances can provide a real-time data packet in which frequency, the rate of change of frequency,
voltage magnitude and breaker status are measured. The proposed method is implemented in five different load schemes
considering DR programs. Comparative analyses are illustrated in this paper to assert the efficiency of implementing DR
programs in which cost function and amounts of shedding loads are decreased. The results demonstrate that DR programs
cannot be used for a big power unbalance in an islanded micro grid. The unintentional delay time imposed by DR and the
small inertia existing in an islanded distribution network restrict the use of DR programs.


Under Frequency Load shedding; Rate of Change of Frequency of Load; Distributed Network Operator; Smart-Grid; Distribution Management System; Demand Response.

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Philip M Anderson and M_ Mirheydar. A low-order system frequency

response model. IEEE Transactions on Power Systems, 5(3):720–729,

Pouya Babahajiani, Hassan Bevrani, and Qobad Shafiee. Intelligent

coordination of demand response and secondary frequency control

in multi-area power systems. In 1st IEEE Conference on New Research

Achievements in Electrical and Computer Engineering (CBCONF),

Tehran, Iran, May, 2016.

Pouya Babahajiani, Qobad Shafiee, and Hassan Bevrani. Intelligent

demand response contribution in frequency control of multi-area power

systems. IEEE Transactions on Smart Grid, 2016.

Yu-Qing Bao and Yang Li. Fpga-based design of grid friendly appliance

controller. IEEE transactions on smart grid, 5(2):924–931, 2014.

Vladimir Chuvychin and Roman Petrichenko. Development of smart

underfrequency load shedding system. Journal of Electrical Engineering,

(2):123, 2013.

B Delfino, S Massucco, A Morini, P Scalera, and F Silvestro. Implementation

and comparison of different under frequency load-shedding

schemes. In Power Engineering Society Summer Meeting, 2001, volume

, pages 307–312. IEEE, 2001.

Amin Gholami, Tohid Shekari, Farrokh Aminifar, and Mohammad

Shahidehpour. Microgrid scheduling with uncertainty: The quest for

resilience. IEEE Transactions on Smart Grid, 7(6):2849–2858, 2016.

D Hazarika and AK Sinha. Method for optimal load shedding in case

of generation deficiency in a power system. International Journal of

Electrical Power & Energy Systems, 20(6):411–420, 1998.

Nick Jenkins. Embedded generation. Power engineering journal, 9(3):

–150, 1995.

M Karimi, P Wall, H Mokhlis, and V Terzija. A new centralized adaptive

underfrequency load shedding controller for microgrids based on a

distribution state estimator. IEEE Transactions on Power Delivery, 32

(1):370–380, 2017.

Aimin Li and Zexiang Cai. A method for frequency dynamics analysis

and load shedding assessment based on the trajectory of power

system simulation. In Electric Utility Deregulation and Restructuring

and Power Technologies, 2008. DRPT 2008. Third International Conference

on, pages 1335–1339. IEEE, 2008.

Pukar Mahat, Zhe Chen, and Birgitte Bak-Jensen. Underfrequency

load shedding for an islanded distribution system with distributed generators.

IEEE Transactions on Power Delivery, 25(2):911–918, 2010.

Behnam Mohammadi-Ivatloo, A Mokari, H Seyedi, and

S Ghasemzadeh. An improved under-frequency load shedding

scheme in distribution networks with distributed generation. Journal of

Operation and Automation in Power Engineering, 2(1):22–31, 2014.

Amin Mokari-Bolhasan, Heresh Seyedi, Behnam Mohammadi-ivatloo,

Saeed Abapour, and Saeed Ghasemzadeh. Modified centralized rocof

based load shedding scheme in an islanded distribution network. International

Journal of Electrical Power & Energy Systems, 62:806–815,

Sara Mullen and Getiria Onsongo. Decentralized agent-based underfrequency

load shedding. Integrated Computer-Aided Engineering, 17

(4):321–329, 2010.

Lukasz Bartosz Nikonowicz and Jaroslaw Milewski. Virtual power

plants-general review: structure, application and optimization. Journal

of Power Technologies, 92(3):135, 2012.

D Prasetijo, WR Lachs, and D Sutanto. A new load shedding scheme

for limiting underfrequency. IEEE Transactions on Power Systems, 9

(3):1371–1378, 1994.

CP Reddy, S Chakrabarti, and SC Srivastava. A sensitivity-based

method for under-frequency load-shedding. IEEE Transactions on

Power Systems, 29(2):984–985, 2014.

Urban Rudez and Rafael Mihalic. Analysis of underfrequency load

shedding using a frequency gradient. IEEE transactions on power delivery,

(2):565–575, 2011.

Urban Rudez and Rafael Mihalic. Predictive underfrequency load

shedding scheme for islanded power systems with renewable generation.

Electric Power Systems Research, 126:21–28, 2015.

H Seyedi and M Sanaye-Pasand. Design of new load shedding special

protection schemes for a double area power system. American Journal

of Applied Sciences, 6(2):317, 2009.

M Sforna and M Delfanti. Overview of the events and causes of the

italian blackout. In Power Systems Conference and Exposition,

PSCE’06. 2006 IEEE PES, pages 301–308. IEEE, 2006.

Tohid Shekari, Farrokh Aminifar, and Majid Sanaye-Pasand. An analytical

adaptive load shedding scheme against severe combinational disturbances.

IEEE Transactions on Power Systems, 31(5):4135–4143,

Lukas Sigrist, Ignacio Egido, and Luis Rouco. A method for the design

of ufls schemes of small isolated power systems. IEEE Transactions

on Power Systems, 27(2):951–958, 2012.

V Tamilselvan and T Jayabarathi. A hybrid method for optimal load

shedding and improving voltage stability. Ain Shams Engineering Journal,

(1):223–232, 2016.

Vladimir V Terzija. Adaptive underfrequency load shedding based on

the magnitude of the disturbance estimation. IEEE Transactions on

Power Systems, 21(3):1260–1266, 2006.

Costas Vournas. Technical summary on the athens and southern

greece blackout of july 12, 2004. National Technical University of

Athens, 2004.

P Wang and R Billinton. Optimum load-shedding technique to reduce

the total customer interruption cost in a distribution system. IEE

Proceedings-Generation, Transmission and Distribution, 147(1):51–

, 2000.

Ding Xu and Adly A Girgis. Optimal load shedding strategy in power

systems with distributed generation. In Power Engineering Society

Winter Meeting, 2001. IEEE, volume 2, pages 788–793. IEEE, 2001.

BAO Yu-Qing, LI Yang,WANG Beibei, HU Minqiang, and CHEN Peipei.

Demand response for frequency control of multi-area power system.

Journal of Modern Power Systems and Clean Energy, 5(1):20–29,

Alireza Zakariazadeh, Omid Homaee, Shahram Jadid, and Pierluigi

Siano. A new approach for real time voltage control using demand

response in an automated distribution system. Applied Energy, 117:

–166, 2014.


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