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SIMULATION STUDY AND PERFORMANCE ANALYSIS FOR THE INTERACTION

BETWEEN NPP AND ELECTRICAL GRID BASED ON MATLAB SIMULINK

ASMAA M. ELSOTOHY1, MOHAMED A. MEHANNA2,

AYMAN A. EISA3 & AHMED S. ADAIL4

1,3Department of Nuclear Safety and Radiological Emergencies, NCRRT, Atomic Energy Authority, Egypt

4Department of Fuel Technology, Hot Laboratory Centre, Atomic Energy Authority, Egypt

ABSTRACT

The electrical voltage is one of the important parameters, which must be considered to assure the safety of any power

system. The secure, safe and reliable operation of Nuclear power plants (NPPs) needs many studies for the interaction

between the NPP and Electrical Grid. This paper presents an analysis to show the mutual interface between electrical grid

and NPP under different scenarios of abnormalities on both the electrical grid and NPP. The pressurized water reactor

(PWR) NPP mathematical models are presented in MATLAB/ Simulink. The responses of NPP key parameters under step

increase and decrease in power demand were studied and presented to evaluate and assess the load following ability of the

NPP. Then the weighted least squares (WLS) state estimation method is used to study the IEEE 30-bus system response

for a sudden shut down and generation loss of NPP by 50%. The IEEE 30 bus system voltage profile is presented and

analysed. This study can contribute to understand the performance of both NPP and electrical grid under different

scenarios of expected disturbances and this can offer certain guidance for the engineering practice.

KEYWORDS: Electrical Grid, NPP, IEEE-30 Bus System, Bus Voltage & Matlab/Simulink

Received: Feb 20, 2020; Accepted: Mar 10, 2020; Published: Jun 05, 2020; Paper Id.: IJMPERDJUN202083

1. INTRODUCTION

The power of NPP has been developing continually in the world, and it is expected to grow greatly in the coming

years [1–4]. Owing to the NPP high safety requirements and high capacity, large abnormalities in electrical systems

may influence seriously on NPP and electrical grids. Thus, ensuring the power networks and NPPs stability and

safety is an important issue [5].

Up to the present time, for safety, economic and environmental considerations, most NPPs operate as base

load stations without participating in the power grid frequency control.

A reliable and stable electrical grid (with reliable distribution systems, transmission systems and

production units) is an essential to the NPP safety [6].

As shown in figure (1), the Output from the generating unit (NPP) is fed to the electrical grid via the

generator transformer. During the normal operation, the electrical power is fed to NPP auxiliaries from the NPP

generating unit via the unit transformers. NPP auxiliaries can be supplied from the electrical grid when the

generator is shut down by opening the generator breaker in the connection to the generator terminals.

To provide an independent electrical power supply to NPP auxiliary equipment, one or more station

Orig

ina

l Article

International Journal of Mechanical and Production

Engineering Research and Development (IJMPERD)

ISSN (P): 2249–6890; ISSN (E): 2249–8001

Vol. 10, Issue 3, Jun 2020, 933-950

© TJPR Pvt. Ltd.

2Department of Electrical Machines and power Engineering, Al-Azhar University, Egypt

934 Asmaa M. Elsotohy, Mohamed A. Mehanna, Ayman A. Eisa & Ahmed S. Adail

Impact Factor (JCC): 8.8746 SCOPUS Indexed Journal NAAS Rating: 3.11

transformers provide the second connection to the grid [7]. This redundancy in power sources to NPP auxiliaries plays an

important role for nuclear safety which is called defence in depth concept.

There are an important technical issues related with the electrical grid –NPP interface. Among these issues are the

sudden increasing or reduction in the electrical power required to supply various consumers or tripping of NPP, which

supplying a major portion of the electrical grid load, these previous disturbances can result leads to an imbalance between

load and the available generation and effect on the grid’s voltage and frequency.

Frequency is one of the important parameters in power system operation, so that for the power system safety and

quality of power delivery Frequency should be maintained around its nominal value. Deviation of the frequency is usually

initiated from the imbalance between power production of generating units and the grid load. When generating units' power

production is smaller than the gird load, the system frequency will drop. In reverse, the frequency will rise when the power

production is larger than the load of the electrical grid. Since the disturbance of grid load is a problem that cannot be

eliminated due to the load demand changing of consumers, the fluctuation of frequency is unavoidable, which needs to be

monitored continuously and controlled within safe levels [8].

To study the interaction between electrical grid and NPP, a detailed model of NPP is required to obtain an overall

picture of what happened in the plant. In the previous studies, there are some detailed models for nuclear power plant have

been proposed for power system stability analysis, among them, some are linear models [9-11] which cannot be used for

large abnormalities such as load rejection. Other models were nonlinear, but some factors that are very important for power

system are not taken into consideration and took a large number of assumptions that used to simplify the model such as

simplifying the reactor model into one fuel node and two coolant nodes, so that the NPP model cant reflect accurately the

interactions between NPPs and the electrical grid [12-17]. In this study, some of previous factors are taken into account, so

the model becomes able to simulate the dynamic behavior of electrical grid and NPP.

This paper presents a model for the Westinghouse PWR NPP using Matlab/ Simulink. Based on this detailed

model, the dynamic responses of NPP under the change of electrical grid loads are studied. Also, impact of the plant

tripping and loss of NPP generation by 50% on the IEEE 30 bus system voltage profile are studied.

Figure 1: Electrical Power Systems of NPP [7].

Simulation Study and Performance Analysis for the Interaction Between 935

Npp and Electrical Grid Based on Matlab Simulink


Mathematical Model of NPP

The NPP can be divided into nuclear steam supply system (NSSS) and balance of plant (BOP) system. The NSSS contains

the reactor connected to steam generator (SG) and a primary or main pump.in addition, there is one pressurizer connected

to the reactor in the containment building. The BOP system mainly consists of turbine and condenser. The PWR objective

is to transfer the energy, which is produced in the reactor to the SG, where it is converted into steam to drive the turbine

generator in order to produce the electrical power (see figure 2).

Figure 2: Overview of a Nuclear Power Generation Process [18].

In this study, dynamic, detailed, and nonlinear mathematical models for the NPP systems of the Westinghouse

pressurized water reactor (PWR) NPP is developed.

1.1 Modelling and of the NPP Nuclear Steam Supply System (NSSS)

Following ref [19], mathematical model for reactor core, pressurizer, SG model and their control systems are simulated in

matlab/simulink as shown in figure 3.The detailed derivations of these models are presented in [12].

Figure 3: The Structure of the NPP Nuclear Steam Supply System Simulink Model.



1.2 Modelling the NPP Balance of Plant System (BOP)

The model development of BOP components of a PWR plant describes models for turbine, speed control system, and

condenser. These models then connected to construct the BOP overall model of NPP.

Description of steam and water flow path in steam turbine system is as following:-

A saturated steam is supplied from the SG to the steam turbine. A portion of this saturated steam enters the

turbine and the remainder bypassed to the reheater to improve the turbine thermal efficiency.

After leaving the nozzle chest the steam expands in high pressure turbine (HPT).

A portion of the steam is extracted to the HP feed water heater (Heater 2). The remainder of the steam enters

the moisture separator that used to remove the water from steam.

The removed water feds to Heater 2.

The remaining steam is superheated in the steam reheater. And then, it enters the low pressure turbine (LPT).

A portion of this steam is extracted to the LP feed water heater (Heater 1). The remainder is expanded in the

LPT to produce the mechanical power.

Figure 4: Representation for the Steam Turbine Flow Diagram.

1.2.1 Turbine Model

It includes models for the nozzle chest, HPT, reheater, moisture separator, LPT, and heater 1, 2.

Turbine M ode l Governing Equat i ons

(1)

Noz zl e Che st Equati on

(2)

(3)

(4)




(5)

High Pressure Turbine (HPT) Equations

(6)

(7)

(8)

Moisture S eparator Equations

(9)

(10)

Where

Reheater Equations

(11)

(12)

(13)

(14)



(15)

(16)

Where

(

Low Pressure Turbine(LPT) Equations

(17)

(18)

Feed Water Heater (1) Equations

(19)

(20)

Feed Water Heater (2) Equation

(21)

(22)

(23)

(24)

Output Power Equations

(25)

(26)

(27)

(28)




(29)

(30)

1.2.2 The Condenser

The condenser is a large surface type heat exchanger. It is equipped with vacuum system, which maintains a constant

pressure in the condenser for steady-state and transient and conditions, and the hot well pumps with their control systems

to control the water level in the hot wells.

Main condenser equations:-

(31)

(32)

(33)

(34)

(35)

(36)

Where,

Main steam valve coefficient

Bypassed steam valve coefficient

Heat conversion factor (5.404)

Constant parameter1 of steam pressure equation (1.27453).

Constant parameter2 of steam pressure equation (1068.8)

Constant parameter of output power equation (1.414)

Fraction of steam extracted from H.P to HPFH (0.1634)

Fraction of steam extracted from L.P. to LPFH (0.2174)

Enthalpy of steam leaving low pressure turbine.

Enthalpy of steam leaving nozzle chest.

Enthalpy of steam at reheater.

Enthalpy of water in high pressure feed water heater (

HPFH ) (280.4)

Enthalpy of water i n low pressure feed water heater

(LPFH) (529.15).

HPFH Heat flow Constant parameter (475).

LPFH Heat flow Constant parameter (863.76)



Reheater Heat flow Constant parameter (22.589)

Steam Enthalpy which leaving LPT.

Steam Enthalpy which leaving nozzle chest (1196.1)

Steam Enthalpy at reheater (1269.7)

Steam Enthalpy at isentropic end point from pressure Pc.

Steam Enthalpy at isentropic end point from pressure Pr.

Saturated water Enthalpy in reheater.

Saturated water Enthalpy in condenser.

Latent water Enthalpy in reheater.

Latent water Enthalpy in condenser.

Nozzle chest Pressure (790).

Reheater Pressure (160).

Steam pressure in steam generator

Output turbine power

Heat transfer rate in reheater (216931).

Nozzle chest Volume (200)

Reheater Volume (20000)

Flow rate of Steam passing through the main steam valve (3959.5).

Flow rate of Steam leaving nozzle chest (3959.5).

Flow rate of Steam leaving HPT (3311.56).

Flow rate of Steam leaving moisture separator (2942.9).

Flow rate of Steam leaving reheater (2942.9).

Flow rate of Steam leaving LPT (2303).

Flow rate of water from HPFH to LPFH.

Flow rate Steam bypassed to reheater (186.36).

Flow rate of Water from reheater to HPFH (186.336).

bled steam from HPT to HPFH

bled steam from HPT to LPFH .

Water droplet rate into the condenser hot wells.

Flow rate of Water condensation.

Flow rate of Steam in condenser.

Outlet flow rate from condenser to LPFH.

Steam Density at nozzle chest (1.7337).

Steam Density at reheater (0.4).

Time constant associated with main condenser .

Time constant related with HPFH .

Time constant associated with LPFH .

Time constant related with HPT .




Time constant related with LPT .

Time constant related with reheater .

Time constant related with main condenser

1.2.3 Turbine Speed Control System

Figure (5) shows a block diagram of a steam turbine speed control system. Initially, according to the electrical generator

design frequency, the speed of the steam turbine is set at a reference value. In case of turbine speed deviation from its set

point, the speed sensor provides a signal to the comparator device. The Speed error signal (difference between actual speed

signals and the speed set point initiates the hydraulic system to an action according to the difference. The hydraulic system

provides the required power for accurate positioning and rapid movement of the steam valve system. Any changes in the

steam valve position will be proportional to the turbine output torque, which ultimately regulates the speed.

Figure 5: Steam Turbine Speed Control System Representation.

(37)

(38)

Where,

The equation Conversion factor

Turbine-generator moment of inertia

Power demand

Torque demand

AS shown in figure 6 with connecting the turbine model with both condenser model and speed control system, the

NPP balance of plant system will be provided.



Figure 6: The Structure of the NPP Balance of Plant System Simulink Model.

2. SIMULATION RESULTS OF INTERACTION BETWEEN ELECTRICAL GRID AND NPP

There are many technical issues related with the electrical grid NPP interface among these issues is the sudden load

rejection to NPP and the tripping of NPP [20, 21].The whole NPP Simulink model is shown in figure 7.

Figure 7: The NPP Simulink Model Structure.

2.1 Effect of Electrical Grid on NPP

Abnormalities in electrical grid lead to transients in NPP. The effect depend on the severity of these Abnormalities, may

lead to NPP islanding or even to reactor tripping. Such Abnormalities adversely effect on the life and performance of the

plant [7].

Supposing the nuclear power plant is the generation on bus (1) of IEEE 30 bus system (see figure 8).




Figure 8: IEEE 30 Bus System Single Line Diagram.

2.2 A Step Increase in Power Demand

As shown in figure 9, assuming that a step increase in power demand by 15% at the time=500 sec occurs. At the beginning

of the load step increase, an imbalance between the turbine mechanical torque and the generator electromagnetic torque

occurs and this leads to the decrease in speed of the turbine firstly. Then, according to the speed error signal the main

steam governor valve will increase the steam flowrate according to demand power. Finally, the turbine mechanical power

and output electrical power will match the connected load, and speed of the turbine will be returned to its set point value.

Also, it is shown that there is permissible decrease in the buses voltage of electrical grid.

(b)

(a)



(d)

(c)

(f)

(e)

Figure 9: Dynamic Responses of the Nuclear Plant During a Step Increase in Demand Power.

(a) Turbine Speed (b) Steam Valve Coefficient, (c) Steam Generator Pressure

(d) Output Turbine Power (e) Electrical Power (f) Voltage Profile of IEEE-30 Bus System.

2.3 A Step Decrease in Power Demand

As shown in figure (10), assuming that a step decrease in power demand by 15% at the time=500 sec occurs. When the

load request sharply decreases, turbine power deviates from its set value. As the governor responses, the control valves

(CVs) close partly to reduce the flow rate of steam. So that there is a decreasing in flow of steam through the turbine, while

the steam temperature and pressure in the SG increase. Thus, the exchange of heat between the primary and the secondary

sides of SG decreases, and the temperature of coolant increases. Then, power of the turbine decreases to provide the

required power demand. Also, the electrical grid voltage will increase responding to the decrease in the load.

(b)

(a)




(d)

(c)

(f)

(e)

Figure 10: Dynamic Responses of the Nuclear Plant During a Step Decrease in Demand Power

(a) Turbine Speed (b) Steam Valve Coefficient, (c) Steam Generator Pressure,

(d) Output Turbine Power, (e) Electrical Power, (f) Voltage Profile of IEEE-30 Bus System.

2.4 Effect of NPP ON Electrical Grid

Due to the large size of NPP, during operating, it plays an effective role in stabilizing the electrical grid. In a situation of

NPP tripping, an imbalance between the required load and the available generation happens. Without an additional

generation, power can be quickly imported through external connections of grid or adding generation quickly, this may

lead to degrading in voltage on the alternate connections of offsite power that may result in loss of offsite power to the

NPP.

The proposed NPP model is implemented on IEEE 30-Bus system to evaluate the effectiveness of NPP model in

this study. An IEEE 30-bus system Single line diagram is showed in figure (8). Data of buses, regulated bus data, data of

lines, capacitors and transformer data for this test system can be found in the standard power system test case archive [22]

The system has 41 branches with 24 loads, 30 buses, 4 transformers, 2 generators and 4 synchronous condensers which are

used only for supporting the reactive power.

To show the effect of NPP abnormalities on voltage profile of IEEE 30bus system, a study for three power flow

cases were presented on the IEEE 30-Bus system. First, the magnitudes of voltage and phase angles were found for the

standard base case without any change on the NPP generation level.

The other two studies were:

Total loss of generation at bus 1 and at bus 2 (NPP shutdown)

loss of NPP generation at bus 1 by 50%



The aim was to study the voltage magnitude of IEEE 30 bus system under these different previous mentioned

cases.

2.5 Steady State Condition

This is the standard base case without any change in generation of the system. The results obtained in case of applying

state estimation method on the system shows that buses 26 and 30 have minimum voltages (Voltage at bus 26 equal 0.9999

pu and Voltage at bus 30, 0.9922 pu) and those are the weakest buses on the system. Therefore, these two buses can be

selected to implement facts on the future work.

Table 1: Base Case Voltage and Phase Angle for IEEE 30 Bus System

Bus No. VM (p.u) VA (deg)

1 1.06 0

2 1.045 -5.3782

3 1.0212 -7.5287

4 1.0123 -9.2794

5 1.01 -14.1488

6 1.0106 -11.055

7 1.0026 -12.8523

8 1.01 -11.7974

9 1.0511 -14.098

10 1.0454 -15.6882

11 1.082 -14.098

12 1.0573 -14.9329

13 1.071 -14.9329

14 1.0425 -15.8245

15 1.0379 -15.9164

16 1.0446 -15.5154

17 1.0402 -15.8499

18 1.0284 -16.5302

19 1.0259 -16.7037

20 1.03 -16.5072

21 1.033 -16.1307

22 1.0335 -16.1164

23 1.0274 -16.3066

24 1.0218 -16.4828

25 1.0176 -16.0546

26 0.9999 -16.474

27 1.0235 -15.5301

28 1.0071 -11.6773

29 1.0037 -16.7593

30 0.9922 -17.6416

VM: Voltage magnitude

VA: Voltage phase angle

2.6 Shutdown of NPP

In case of a sudden shutdown of NPP at bus 1 occurs (bus 1 presents 85% of the total generation of IEEE 30 bus system),

the voltage of all buses reduced and goes out the safety limits. This NPP outage will lead to a significant generation loss

for the grid. In this case, the grid must have reserves enough to warrant voltage stability of the system during down-times

or shutdown of NPP.

On the other hand, in case of considering NPP shutdown at bus 2 (bus 2 presents 15% of the IEEE 30 bus system




total generation), buses voltage will be reduced to a level higher than the voltage in case of assuming shut down of NPP at

bus1. The results containing comparison of nodal voltage magnitudes with the IEEE 30 bus system standard base case

shown in Figure 11.

0.75

0.8

0.85

0.9

0.95

1

1.05

1.1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Bu

s V

olt

age

(pu

)

NO. of Bus

Steady state operation Generation 1 shutdown Generation 2 shut down

Figure 11: IEEE 30-Bus System Voltage Magnitude in Case of Steady

State and Total Loss of Generation (NPP Shutdown) at Buses 1, 2.

2.7 Loss of Generation by 50%

Now, the test network was studied in case of loss of generation at bus number 1 by 50%. In this case, the voltage of all

buses reduced as shown in figure 12, this is due to losing a high effective percentage of generation.

0.75

0.8

0.85

0.9

0.95

1

1.05

1.1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Bu

s V

olt

age

(pu

)

NO. of BusSteady state operation Decrease Generation 1 by 50%

Figure 12: IEEE 30-Bus System Voltage Magnitude in Case of Steady

State and Loss of Generation by 50% at bus 1.

3. CONCLUSIONS

This paper presented a model for both NPP and test case IEEE 30 bus system through a MATLAB program, in order to

study the mutual interface between electrical grid and NPP. A study for NPP response to step increase and decrease in

power demand is performed and analyzed. The NPP fast response to abnormalities showed the load following ability of

this plant, as it follows the changes in the load safely with a good response. Also, a study for the impacts of the NPP on the

voltage profile of the power network under abnormal conditions of NPP sudden shutdown and loss of NPP generation by



50% based on the power system state estimation load flow method is presented. It is found that the sudden shutdown of

NPP capable of decreasing the voltage profile at the almost buses of system, depending on the percentage of generation

lost comparing with the total generation of the network. Also, the buses voltages in case of loss of generation by 50% are

plotted, analyzed and compared with the standard base case. Hence, the objective of this current work is to present the

unbalance that occurs in the electrical network, in case of losing a large percentage of generation.

REFERENCES

1. Medium- and Long-Term Nuclear Power Development Plan; National Energy Administration of China: Beijing, China, 2012.

2. Energy Information Administration. International Energy Outlook 2009; U.S. Department of Energy:

3. Washington, DC, USA, 2009.

4. Zhou, Y. Why is China going nuclear? Energy Policy 2010, 38, 3755–3762. [CrossRef]

5. Adamantiades, A.; Kessides, I. Nuclear power for sustainable development: Current status and future

6. prospects. Energy Policy 2009, 37, 5149–5166. [CrossRef]

7. Trehan, N.K.; Saran, R. Nuclear Power Revival. In Proceedings of the IEEE Nuclear Science Symposium

8. Conference, Portland, OR, USA, 19–25 October 2003.

9. IAEA "Design of Electrical Power Systems for Nuclear Power Plants" IAEA SAFETY STANDARDS SERIES No. SSG-34,

IAEA ISBN 978–92 –0–109314–1, ISSN 1020–525X, 2016.

10. Adeyemo, I., OA FAKOLUJO, and GA ADEPOJU. "Ant colony optimisation approach To selective harmonic elimination in

multilevel Inverter." IMPACT: International Journal of Research inEngineering & Technology 3 (2015): 31-42.

11. International Atomic Energy Agency, “electric grid reliability and interface with nuclear power plant”, series No. NG-T-3.8,

VIENNA, 2012

12. P.wang, Yan fu, Xinyu wei, F uyu zhao "simulation study of frequency control characteristic of a generation III= nuclear

power plant" Elsevier 2018

13. Schulz, R.P.; Turner, A.E. Long-Term Power System Dynamics—Phase II; Final Report for EPRI Research Project 764-1,

Report No. EL-367; General Electric Company: Schenectdy, NY, USA, 1977.

14. HOR, Kamal Kis, and Rekha Jha. "Control of Dc Servomotor Using Relay and Pole Placement Method By Matlab Simulink."

International Journal of Electrical and Electronics Engineering (IJEEE) 3. 3, May 2014, 29-38

15. Di Lascio, M.A.; Moret, R.; Poloujadoff, M. Reduction of program size for long-term power system simulation with

pressurized water reactor. IEEE Trans. Power Appar. Syst. 1983, PAS-102, 745–751. [CrossRef]

16. Kerlin, T.W.; Katz, E.M. Pressurized Water Reactor Modeling for Long-Term Power System Dynamic Simulation; Final

Report for EPRI Research Project 764-4, Report No. EL-3087; Tennessee University: Knoxville, TN, USA, 1983.

17. Elashkar, Magdy Ali. "the Use of Simulation Techniques in the Development of Non-Technical Skills for Marine

Officers." International Journal of General Engineering and Technology (IJGET) 5.5 (2016): 19-26.

18. Masoud Naghedolfeizi “Dynamic modelling of pressurized water reactor plant for diagnostic and control”,M.Sc. Thesis, The

University of Tennessee, Knoxville December 1990.

19. Samet Egemen Arda, “Implementing a Nuclear Power Plant Mo mdel for Evaluating Load-Following" M.Sc. Thesis, April

2013.




20. J. Tan, Y. Zheng '' Detailed Nuclear Power Plant Model for Power System Analysis Based on Matlab-Simulink'' Applied

Mechanics and Materials Vols 291-294 (2013) pp 561-570.

21. ]S.A.KOTB “impact the nuclear power plant on electrical grid” Ph.D. dissertation, Dept. Elec. Eng., Alazhar University,

Egypt 2010.

22. M.K .Shaat, M. Mahmoud, s. Kotb “Influence of Egyptian Electrical Grid and nuclear power plants under disturbances based

on PSS/E” Eleventh Arab Conference on the Peaceful Uses of Atomic Energy. Khartoum. Sudan. 16-20 December 2012

23. Gopalakrishna, H. D., et al. "Crashworthiness of Automobile in a Vehicle-to-Pole Crash Simulation." International journal of

automobile engineering research & development, ISSN (E), 2278 9413 (2014).

24. ]Amr Adel Fathy Mohammed, “impact of interconnecting a nuclear power plant on the performance of an existing power

system network”, M.Sc. thesis in Electrical Power and Machines Engineering. Cairo University, Egypt, October 2011.

25. Office of Electricity Delivery and Energy Reliability, U.S. Department of Energy, DOE/OE-0017 "United States Electricity

Industry Primer", July 2015

26. Asmaa M. Elsotohy, Ayman A. Eisa, Ahmed S. Adail, Mohamed A. Mehanna. "Detailed and verified NPP model for safe

interconnection with electrical grid", Electrical Engineering, 2020

27. Dr. John H. Bickel, “Grid Stability and Safety Issues Associated with Nuclear Power Plants”, Evergreen Safety and

Reliability Technologies, LLC 2001.

28. S. A. Jackson, “Statement Submitted by the United States Nuclear Regulatory Commission to the Special Committee on the

Year 2000 Technology Problem United States Senate Concerning Year 2000 Readiness of the Utility Industry”, June 12, 1998.

29. Berrouk, B. Ali Rachedi, A. Lemzadmi, K. Bounaya and H. Zeghache, "Applications of shunt FACTS controller for voltage

stability improvement," 2014 International Conference on Electrical Sciences and Technologies in Maghreb (CISTEM), Tunis,

2014, pp. 1-6.

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