Helwan University

From the SelectedWorks of Omar H. Abdalla

March 7, 2019

Steady-State and Transient Performances of theEgyptian Grid with Benban Photovoltaic ParkOmar H. AbdallaHady H. FayekA. M. Abdel Ghany

Available at: https://works.bepress.com/omar/66/

205 Cigre Egypt 2019

Steady-State and Transient Performances of the Egyptian Grid with Benban Photovoltaic Park

Omar H. ABDALLA

Faculty of Engineering, Helwan University

(Egypt)

Hady H. FAYEK

Faculty of Engineering, Heliopolis University

(Egypt)

A. M. ABDEL GHANY

Faculty of Engineering, 6 October University - on leave from Helwan University

(Egypt)

SUMMARY

The paper presents steady-state and transient studies to assess the impact of connecting the

world’s largest photovoltaic (PV) park at Benban to the 500/220 kV interconnected

transmission system of Egypt. Three scenarios are considered to connect the Benban PV Park

to the Egyptian grid: Scenario 1 is the connection to the grid at both 500 and 220 kV levels,

Scenario 2 is the connection to 220 kV level only and Scenario 3 is the connection to the 500

kV level only. The DIgSILENT PowerFactory professional software is used to simulate the

system and to obtain the results in all scenarios. The results include percentage of transmission

line loadings, busbar voltages, (active and reactive) grid losses, in addition to 3-phase fault and

1-phase fault levels. Also, simulation studies have been performed to assess the transmission

system transient responses to Benban Park full outage. Voltage deviation index is also

calculated and compared in all scenarios.

The simulated Egyptian grid includes the 500/220 kV grid with existing generating plants,

in addition to the world’s three largest combined cycle power plants, of 4800 MW each,

(recently commissioned at Beni Suef, Burullus and New Capital), the world’s largest

photovoltaic power park of 1800 MW which is under construction at Benban and the 540 MW

Gabalzeet wind farms. The results have shown that the best choice is to connect Benban PV

Park to the grid at both 500 kV and 220 kV levels.

KEYWORDS

Benban photovoltaic park - Egyptian grid - Load flow - Transient response.

E-Mail: ohabdalla@ieee.org

1. INTRODUCTION

Egypt is facing many challenges in terms of energy generation and consumption. The

consumption is in continuous increase due to the increasing of population and expected future

developments in various fields. In addition to conventional power generation, the Egyptian

Ministry of Electricity and Renewable Energy is establishing new large solar parks and wind

farms to cope with the growth of demand.

Egypt is one of the countries, which has favorable solar energy conditions and good potential

for solar energy utilization. The amount of solar energy incidence per square meter varies

between 5 and 8 kWh per day with duration of 3000-4000 hours per year [1]. A national program

to develop renewable energy systems was started in 1957 in the National Research Center of

Egypt [1]. Since then many academic institutions have been involved in academic research on

different aspects of solar cell technology. Some institutions have been involved in field

applications of Photovoltaic (PV) systems for community development. The potential for

practical use of PV power was first tested in the field of Basaisa Village in (Al-Sharkiya

Governorate) in September 1977 [1]. A solar module (18-watt peak) was used to power a 12-inch

black and white TV set which was installed in the common hall “Mandara” of Basaisa. Since

then photovoltaic power generation began to be used in various applications in Egypt [1].

The PV parks size has increased progressively over the last decade with frequent new

capacity records worldwide. In Canada, the 97 MW Sarnia Photovoltaic Power Plant went online

in 2010 [2]. In China, Huanghe Hydropower Golmud Solar Park reached 200 MW in 2012 [3]. In

August 2012, Agua Caliente Solar Project in Arizona reached 247 MW only to be passed by

three larger plants in 2013 [4]. In 2014, two plants were tied as largest: Topaz Solar Farm, a PV

solar plant at 550 MWAC in central coast area and a second 550-MW plant, the Desert Sunlight

Solar Farm located in the far eastern desert region of California [5]. These two plants were

superseded by a new larg facility in June 2015 when the 579 MWAC Solar Star project went

online in the Antelope Valley region of Los Angeles County, California [5]. In 2016, a

photovoltaic power Longyangxia Dam Solar Park with 850 MW capacity was installed in

Gonghe County, Qinghai, China [6]. In 2016, Tengger Desert Solar Park with 1547 MW

capacity was installed in China [7]. In 2018, a park with 1365 MW installed capacity was

established in India [8]. In Egypt, Benban Photovoltaic Park with a capacity of 1800 MW will be

the largest photovoltaic power station worldwide (without energy storage). It is located in Upper-

Egypt and will feed the grid and connected through 220 and/or 500 kV transmission grids.

Electricity utilities over the world perform power system studies by using digital models to

simulate electric grids. The models are used for long-term and short-term planning studies

including steady-state and dynamic analyses. These models are based on computer packages with

versatile facilities to represent large scale power systems, including generators, turbines, exciters,

transformers, transmission lines, loads and various control devices [9]. DIgSILENT

PowerFactory software provides highly specialized services in the field of electrical power

systems for energy transmission, distribution, generation, industrial plants, renewable energy and

smart grid [10].

The objective of this paper is to study the impact of the world’s largest photovoltaic park

(Benban) on the steady-state and transient performances of the Egyptian 500/220 kV grid. Three

proposed scenarios are considered to connect Benban PV Park to the Egyptian grid: (i) 500 and

220 kV grids; (ii) 220 kV grid only; and (iii) 500 kV grid only. The steady-state analyses include

load flow studies, short circuit calculations, contingency analysis and voltage performance.

Transient analysis includes system voltage and frequency responses to tripping Benban PV park.

The paper is organized as follows, Section II describes the main power system of Egypt

levels 500 and 220 kV. Section III provides a brief description about Benban photovoltaic power

plant. Section IV illustrates the PV and wind systems and modeling. Section V presents the main

results of load flow, power losses and short circuit analyses. Section VI presents transient

analysis of Benban photovoltaic park forced outage. Section VII summarizes the main

conclusions.

2. EGYPTIAN POWER GRID

The simulated model of the Egyptian grid has been fully described in [10] which represent

the conditions at peak demand of 2016. Here, the model has been updated to include the five

new power stations and their associated new transmission facilities which are now under

construction or even partially in service. The new power plants include the world’s three largest

combined cycle power stations with 4800 MW each (8×400 MW GT + 4×400 MW ST) installed

capacity; located in Burullus, Beni Suef and New Capital in addition to the Benban world’s

largest photovoltaic park with 1800 MW under construction near Aswan and the expanded

Gabalzeet wind farms to reach 540 MW. Briefly, the simulated grid consists of: 23 single-circuit

500 kV transmission lines, 172 double-circuit 220 kV transmission lines, 23 single-circuit 220

kV transmission line, 1 four-circuit 220 kV transmission, 38 (500/220 kV) autotransformers, 213

two-windings unit transformers in addition to loads and static reactive power compensators

(reactors and capacitors). A geo-schematic diagram of the upgraded Egyptian power grid is

shown in Figure 1 [11]. In this paper the focus will be on the Upper-Egypt zone which includes

Benban park.

Based on the Egyptian Grid Code [12], the 500 kV and 400 kV transmission system shall be

planned and operated so that no single contingency, at these voltage levels, results in

unacceptable frequency, voltage or large-scale demand disconnection; this known as (N-1)

criterion. The 220 kV, 132 kV and 66 kV transmission systems shall be planned and operated so

that (N-2) criterion is maintained.

3. BENBAN PHOTOVOLTAIC PARK

The Benban PV power plant with installed capacity 1800 MW site is located in the western

desert, approximately 40 km northwest of Aswan city. The area designated for the project is a

desert land owned by the National Renewable Energy Authority (NREA). The project site is

divided into 41 plots [13]. These are arranged in 4 rows. The plots range in size from 0.3 km2

to

1.0 km2. The site will have four 220 kV substations, to be developed by NREA and the Egyptian

Electricity Transmission Company, at the perimeters to the east and south substations [13]. Each

Benban project will transmit its power from the site boundary to one of the four on-site

substations using underground cables. For the further evacuation of power from those substations

the Benban site is close to two transmission corridors. There is a corridor with 2 x 500 kV at a

distance of approximately 0.5 km from the eastern site border, between the site and Aswan-

Luxor Highway. The second corridor of 220 kV lines is located at a distance of approximately 12

km [13]. Figure 2 shows the position of the park with respect to the 500 kV transmission grid and

the 220 kV transmission grid.

4. PHOTOVOLTAIC AND WIND ENERGY SYSTEMS

A. Photovoltaic System

A photovoltaic system is a green power source, which converts sunlight directly to electricity.

The main advantages of the PV systems are that they require no fuel, produce no emissions, and

involve no moving parts. Figure 3 shows the main components of a PV power plant, it consists of

a large number of solar arrays, DC/DC converters, DC/AC inverters, filters, and step up

transformers [14]. A solar panel, which consists of several solar cells, produces only a small

amount of current and voltage. In order to produce a large amount of electric power, the solar

panels are connected into arrays. The output voltage from a PV array changes with solar

radiation and ambient temperature. In order to connect the PV system to the transmission grid,

the output DC voltage from PV system should be first regulated by a DC/DC converter and then

converted to AC voltage by a DC/AC inverter. A filter is used to eliminate harmonics. The power

electronic components (DC/DC converter, DC/AC inverter, and filter) have the tasks to

guarantee safe and efficient operation, to track the maximum power point of the PV system, and

to maintain power quality of the PV system output [14].

The photovoltaic park is represented in DIgSILENT as a static generator [10]. The static

generator has 3 modes of operation which are PQ mode, voltage control mode and droop mode

[10]. In this research the mode of operation is selected to be voltage control mode and the

reactive power limits are set to achieve 0.95 lead and 0.95 lag (at rated output) based on the

Egyptian grid code for integrating medium and large scale solar systems to the grid as illustrated

in Figure 4. [15, 16].

B. Wind Farm

DIgSILENT includes two built-in DFIG models. The first will be referred to as model 1 in

the following while the second will be referred to as model 2 in the following. In model 1, the

rotor side’s power factor is controlled to be one. The controller is however not instantaneous and

small amounts of reactive power are either produced or consumed [10]. In model 2, the DC-link

is hidden, specifically concerning the load flow calculations [10]. With model 1, it is only

possible to define the active and reactive powers produced by the stator. There is no possibility to

define it as a voltage control or PQ bus. This puts some strong limitations on the load flow

behavior of this model, since we are generally interested in total power and not only stator

power. With model 2 however, the user can define the generator bus as a voltage control or PQ

bus [10]. In this research wind generation is simulated as model 2 and defined as voltage control

bus.

Figure 1: Geo-schematic diagram of the upgraded Egyptian power grid [11].

DC/AC

Converter

DC/DC

Converter

Grid

Figure 3: Photovoltaic generating system main components.

Figure 4: P-Q capability chart for renewable power plants [15]

Left for the medium-scale solar parks

Right for the large-scale solar parks

Figure 2: Benban photovoltaic park and 500 /220 kV transmission grids [13].

0

10

20

30

40

50

60

70

80

90

100

110

-40 -30 -20 -10 0 10 20 30 40

Act

ive

Po

wer

P (

%)

Rective Power Q (%)

5. STEADY STATE ANALYSIS

The aim of the study is to assess the impact of Benban photovoltaic park connection to the

500/220 kV transmission grid. The assessment will be presented in terms of line loadings,

busbars voltages, three-phase and single-phase fault levels and total losses in each scenario. The

three scenarios for the park connection to the grid are:

1. Connection to both 500 kV and 220 kV grids by connecting Benban to the 220 kV using

line in line out of the transmission line between Rabt El-Khazan and Luxor substations

and also connecting the park to the 500 kV using line in line out to the 500 kV

transmission line between High Dam (HD) and Nagi Hamady (NH) substations. In this

scenario, 220/500 kV step-up transformers are required.

2. Connection to the 220 kV grid only by connecting Benban to the 220 kV by using line in

line out of the transmission line between Rabt El-Khazan and Luxor substations.

3. Connection to the 500-kV grid only by using line in line out of the 500 k V transmission

line between HD and NH substations.

Load flow studies are performed and the results are listed in Tables I, II and III. Table I

shows that the voltages at all the buses with all scenarios are within the allowable range 95 –

105% of the rated values. Table II shows that all the lines in Scenario 1 and Scenario 3 are

loaded below the lines thermal limits while there are two lines in the Scenario 2 highly

overloaded above the thermal limits. This indicates that if the park is connected to the 220 kV

grid only, reinforcements for the overloaded lines are required. Table III shows that Scenario 1

results in lower total active and reactive power losses compared to the corresponding losses in

the other two connection scenarios.

Table I

Busbar voltage in normal conditions

Bus bar Name Nominal (kV) Voltage (PU)

Scenario 1 Scenario 2 Scenario 3 Without PV

Al-Khazan 220 1.00 1.02 1.00 0.99

Benban 500 500 0.99 NA 0.99 NA

Benban220 220 1.00 1.01 1.00 NA

HD220 220 1.00 1.01 1.00 0.99

HD500 500 1.00 1.03 1.00 0.98

NH220 220 0.97 0.97 0.97 0.97

NH500 500 1.00 1.00 1.00 1.00

NOKRA 220 1.00 1.01 1.00 0.99

Rabt El-Khazan 220 1.00 1.01 1.00 0.99

Refa 220 0.97 0.97 0.97 0.97

Salwa 220 0.99 1.00 1.00 0.99

Sfaga 220 0.96 0.97 0.96 0.96

South Qena 220 0.97 0.97 0.97 0.97

Gerga 220 0.95 0.95 0.95 0.95

Tama 220 0.96 0.96 0.96 0.96

Table II

Line loading at normal conditions

Line Nominal

Voltage

(kV)

Line Loading (%)

From To Scenario 1 Scenario 2 Scenario 3 Without

Benban

NH500 Benban 500 500 20.53 NA 22.04 NA

HD500 Benban 500 500 8.81 NA 7.28 NA

NH500 HD500 500 NA 20.23 NA 23.59

HD220 Rabt Khzan 220 48.82 188.16 40.28 38.90

NOKRA Salwa 220 33.76 47.59 3.71 3.68

Rabt Khzan Salwa 220 37.24 44.74 56.34 62.27

Armanet Salwa 220 24.00 31.03 19.12 21.13

Luxor Armanet 220 38.80 59.71 19.63 20.95

Salwa Luxor 220 46.89 60.32 36.94 40.39

South Qena NH220 220 19.11 13.88 24.45 22.25

South Qena Luxor 220 47.5 59.71 37.97 40.89

Gerga NH220 220 19.35 20.73 19.19 19.69

Tama Gerga 220 57.1 56.02 57.82 57.48

Rabt Khzan Benban220 220 4.81 145.39 NA NA

Table III

Total active and reactive power losses in the 500/220 kV Egyptian grid

Grid losses Scenario 1 Scenario 2 Scenario 3

Total Active Power Losses (MW) 807.86 845.26 829.41

Total Reactive Power Losses (MVAR) 6540.53 7119.10 6685.42

Short-circuit studies are performed and the results are listed in Table IV. The three-phase and

single phase short circuit currents in are all in the allowable range for all the scenarios.

Transmission line contingency analyses are performed to assess the effect of line outages in

each scenario. Table V shows that there are three lines highly overloaded in Scenario 2 if

Benban-Rabt khazan double circuit line went out of service (N-2) while in Scenario 1, the

loading will remain below the thermal limits at this outage. The voltage magnitudes have been

calculated for this contingency, and we found that in Scenarios 1 Scenario 2 the voltages are

within the allowable range. Table VI shows the loading of the lines if a single circuit outage

occurred in the HD-Benban 500 kV line (N-1). It is noted that all lines are loaded below their

thermal limits. It is also noted that the voltage magnitudes at all busbars are within the allowable

range in Scenario 1 and Scenario 3.

Table VII illustrates that the Benban Park can be connected to the 220 kV grid only till 60%

of its total capacity without any exceeding the thermal limits of the lines. The results show the

three lines which are overloaded based on the results of normal operating conditions and line

contingency shown in Table II and Table V respectively. The maximum capacity of Benban park

in Scenario 2, without enforcements, is about 1100 MW.

Table IV

Three-phase and single-phase short circuit currents

Bus bar Name

Nominal

Voltage

(kV)

Fault Current (kA)

Scenario 1 Scenario 2 Scenario 3

3-ph. 1-ph. 3-ph. 1-ph. 3-ph. 1-ph.

AL Khzan 220 22 18 22 21 23 21

Benban 500 500 13 12 NA 12 10

Benban220 220 21 19 22 20 11 9

HD220 220 22 19 19 17 18 16

HD500 500 18 17 18 17 17 14

NH220 220 17 16 17 16 17 14

NH500 500 13 11 12 10 12 9

Nokra 220 10 9 9 8 3 3

Rabt Khzan 220 23 21 18 15 22 21

Refa 220 16 14 16 13 17 14

Salwa 220 8 8 8 6 8 6

Sfaga 220 7 6 7 5 7 6

South Qena 220 12 11 12 10 11 10

Gerga 220 11 10 11 9 11 8

Tama 220 11 9 11 8 11 10

Table V

Line loading in case of outage of 220 kV line between Rabt Khazan and Benban

(two circuits outage)

Transmission Line Nominal

Voltage (kV)

Line Loading (%)

From To Scenario 1 Scenario 2

NH500 Benban 500 500 20.31 NA

HD500 Benban 500 500 12.88 NA

NH500 HD500 500 NA 21.65

HD220 Rabt Khzan 220 60.54 127.78

NOKRA Salwa 220 57.03 76.16

Armanet Salwa 220 24.61 26.11

Luxor Armanet 220 19.93 24.89

Salwa Luxor 220 37.74 40.96

South Qena NH220 220 23.99 18.54

South Qena Luxor 220 36.64 49.20

Benban Luxor 220 19.29 147.17

Tama Gerga 220 57.75 56.74

Rabt Khzan Salwa 220 14.97 121.89

Table VI

Line loading in case of 500kV line outage connecting between HD and Benban

(single circuit outage)

Transmission Line Nominal

Voltage (kV)

Line Loading (%)

From To Scenario 1 Scenario 3

NH500 Benban 500 500 41 69

HD500 Benban 500 500 22 20

NH500 HD500 500 NA NA

HD220 Rabt Khzan 220 44 54

NOKRA Salwa 220 24 4

Armanet Salwa 220 21 27

Luxor Armanet 220 22 27

Salwa Luxor 220 41 52

South Qena NH220 220 23 17

South Qena Luxor 220 42 52

Benban Luxor 220 13 NA

Tama Gerga 220 57 57

Rabt Khzan Salwa 220 38 80

Table VII

Line loadings in Scenario 2 when the park operated at different capacities

Park generated power in

MW

(% of park full capacity)

HD220-Rabt

Khazan line

loading in %

Benban-Rabt Khazan

line loading in %

Benban-Luxor line

loading in %

0 (0%) 32 83 12

180 (10%) 11 61 14

360 (20%) 10 39 18

540 (30%) 21 28 19

720 (40%) 54 10 21

900 (50%) 75 30 23

1080 (60%) 98 53 24

1260 (70%) 120 75 26

1440 (80%) 142 98 28

1620 (90 %) 164 121 30

1800 (100%) 188 145 32

6. TRANSIENT STUDIES

Simulation studies have been performed to assess the transmission system transient responses

to the Benban photovoltaic park outage; assuming that the busbar connecting the park to the grid

was considered as a voltage controlled bus. The dynamic model of the system is used. Sample

results are presented here to show the performance of the system when it is subjected to

photovoltaic generation contingency in each scenario. Figure 5, Figure 6 and Figure 7 show the

voltage and frequency responses at some busbars in the Upper Egypt region. The figures show

the responses to tripping the Benban photovoltaic park when it is supplying 1800 MW to the grid

in the three scenarios. The transient results show that the transmission system is stable and

capable of withstanding this type of severe forced outage in the three scenarios.

Figure 5. Voltage and frequency responses when the system is subjected to Benban park outage

in Scenario 1.

Figure 6. Voltage and frequency responses when the system is subjected to Benban park outage

in Scenario 2.

Figure 7. Voltage and frequency responses when the system is subjected to Benban park outage

in Scenario 3.

The reason behind the increase in voltages in Figures 5 and 6 after the outage of the

photovoltaic park is that Benban park was operated as a voltage control bus and was absorbing

reactive power. When it goes suddenly out of service, the released reactive power increases the

voltage magnitudes of some load buses. It is also noted that the frequency deviation will reach

zero Hz after some oscillations in the three scenarios due to the presence of enough reserve.

Table VIII shows a comparison of system performances in the three scenarios in terms of

voltage deviation index (VDI) [17] as illustrated in (1). The number of load buses in the simulated

Egyptian power system is equal to 81.

𝑉𝐷𝐼 = √1

𝑛𝐿∑ (𝑉𝑖𝑛 − 𝑉𝑖)

2𝑛𝐿𝑖=1 (1)

where:

𝑛𝐿 is the number of load buses

𝑉𝑖𝑛 is the nominal voltage of the load bus

𝑉𝑖 is the actual load bus voltage The results in Table VIII show that Scenario 1 achieves the minimum voltage deviation index

which indicates that the voltage profile in this scenario is better than that of Scenario 2 and

Scenario 3.

Table VIII Voltage Deviation Index

Case Voltage Deviation Index

Scenario 1 Scenario 2 Scenario 3

Park outage (Voltage control bus) 0.024 0.029 0.028

Park outage (PQ bus) 0.022 0.028 0.026

HD-NH 500 kV line (single circuit outage) NA 0.031 NA

HD-Benban 500 kV line (single circuit outage) 0.024 NA 0.031

NH-Benban 500 kV line (single circuit outage) 0.027 N/A 0.029

Benban-Luxor 220 kV line (double circuit outage) 0.024 0.034 NA

7. CONCLUSION

The study presented comparison between the system performance when Benban photovoltaic

park is connected to the Egyptian grid at three different scenarios. The results show that the

connection using scenario 1 (connecting the park to both 500 and 220 kV grids) has better

performance than that of the other two scenarios in terms of total power losses. The results also

show that operating the park at more than 60% of its capacity will lead to lines overloading if it is

connected to the 220 kV grid only which requires lines reinforcement for this scenario to be

implemented. The results also proved that scenario 1 has the best performance in terms of

voltage deviation index when the system is subjected to the park outage when operated as a

voltage control bus and as a PQ bus. The results also prove that park outage don’t drive the

system to a frequency deviation due to the presence of high reserve in addition the photovoltaic

park drives the system to achieve better voltage deviation index in different cases using scenario

1 than that of the other scenarios.

BIBLIOGRAPHY

[1] ISESCO Journal of Science and Technology.

(https://www.isesco.org.ma/ISESCO_Technology_Vision/NUM01/doc/Said%20H.%20EL-

Hefnawi.pdf)

[2] Solaripedia.

(http://www.solaripedia.com/13/303/3431/sarnia_solar_farm_photovoltaics.html)

[3] Star solar. (https://www.pvsolarchina.com/chint-solar-successfully-completed-golmud-

20mw-photovoltaic-power-station.html)

[4] Waybackmachine.

(https://web.archive.org/web/20130501122808/http://investor.firstsolar.com/releasedetail.cf

m?ReleaseID=706034)

[5] Renewable Energy World. "DOE Closes on Four Major Solar Projects" (30 September

2011)

[6] Eric Wesoff. "Solar Star, Largest PV Power Plant in the World, Now Operational”

(Greentech Solar, https://www.greentechmedia.com/articles/read/solar-star-largest-pv-

power-plant-in-the-world-now-operational#gs.7XNWmi0a, 26 June 2015)

[7] Electrek. (https://electrek.co/2018/01/29/10-really-cool-solar-power-installations/)

[8] NDTV. (https://www.ndtv.com/india-news/countrys-biggest-solar-park-at-the-heart-of-

indias-clean-energy-push-1696271)

[9] Omar H. Abdalla, A. M. Abdel Ghany, and Hady H. Fayek. "Development of a digital

model of the Egyptian power grid for steady-state and transient studies" (11th International

Conference on Electrical Engineering (ICEENG-11), Paper No 83-EPS. Cairo, Egypt,

https://works.bepress.com/omar/31/, 3-5 April 2018)

[10] PowerFactory DIgSILENT GmbH. (http://www.digsilent.de)

[11] Global Energy Network Institute. (https://www.geni.org/)

[12] EETC. “Transmission Grid Code” (Egyptian Electricity Transmission Company, EETC,

Cairo, Egypt. http://www.eetc.net.eg/grid_code.html)

[13] New and Renewable Energy Authority (NREA) - EcoConServ Environmental Solutions.

“Benban 1.8 GW PV solar park, Egypt strategic environmental & social assessment: Final

report” (http://www.eib.org/attachments/registers/65771943.pdf, Feb. 2016, pages 1-210)

[14] O. H. Abdalla, R. Al-Badwawi, H. Al-Hadi, H. Al-Riyami and A. Al-Nadabi. "Steady-state

and transient performances of Oman transmission system with 200 MW photovoltaic power

plant" (2012 IEEE Energytech, Cleveland, OH, 2012, pages 1-6)

[15] EgyptEra. “Solar Energy Grid Connection Code” (Egyptian Electric Utility and Consumer

Protection Regulatory Authority, EgyptEra, Cairo, Egypt, http://www.egyptera.org)

[16] Omar H. Abdalla. “Technical Requirements for Connecting Medium and Large Solar

Power Plants to Electricity Networks in Egypt”, (Journal of the Egyptian Society of

Engineers, Vol. 57, No. 1, https://works.bepress.com/omar/42/, June 2018, pages 25-36)

[17] Omar H. Abdalla, Rashid Al-Badwawi, Hilal Al-Hadi, and Hisham Al-Riyami. “Steady-

State and Dynamic Performance of Oman Transmission System with Diesel-Engine Driven

Distributed Generation” (Proc. of the “46th

International Universities Power Engineering

Conference (UPEC 2011)”, South Westphalia University of Applied Sciences, Soest,

Germany, 5-8 September 2011)