Energy and Power Engineering, 2009, 72-80
doi:10.4236/epe.2009.12011 Published Online November 2009 (http://www.scirp.org/journal/epe)
Copyright © 2009 SciRes EPE
Wind-Solar Hybrid Electrical Power Production to
Support National Grid: Case Study - Jordan
Ghassan HALASA1, Johnson A. ASUMADU2
1Electrical Engineering Department, University of Jordan, Amman, Jordan
2Electrical and Computer Engineering Department, Western Michigan University, Kalamazoo, USA
Email: halasa@ju.edu.jo, johnson.asumadu@wmich.edu
Abstract: The paper presents the next generation of power energy systems using solar- and wind-energy sys-
tems for the country of Jordan. Presently with the oil prices are on the rise, the cost of electrical power pro-
duction is very high. The opportunity of a large wind and solar hybrid power production is being explored.
Sights are chosen to produce electricity using the wind in the Mountains in Northern Jordan and the sun in
the Eastern Desert. It is found that the cost of windmill farm to produce 100 - 150 MW is US$290 million
while solar power station to produce 100 MW costs US$560 million. The electrical power costs
US$0.02/kWh for the wind power and US$0.077 for the solar power. The feasibility for using wind and solar
energies is now when the price oil reaches US$ 100.00 per barrel. The paper also discusses different power
electronics circuits and control methods to link the renewable energy to the national grid. This paper also
looks at some of the modern power electronics converters and electrical generators, which have improved
significantly solar and wind energy technologies.
Keywords: solar energy, wind energy, hybrid energy system
1. Introduction
The concept of solar and wind energies dates back to
nearly 7,000 years ago [1]. However, in the late 1800s
the Danes developed the first wind turbines to produce
commercial electricity [1–4]. In the early 1900s small-
scale wind turbines became more widely used around
Europe especially in the rural areas for producing elec-
tricity using old car generators and carved rotors. The
wind power brought electricity to the rural areas and the
electrical power was used to charge batteries to run ra-
dios and to draw water from deep wells [2]. Except in
Denmark where wind power production and research
continued, wind power did not play any major role in the
generation of electricity until the late 1900s.
The rapid growth of solar and wind powers is due in
part to favorable global political climate towards these
energies, efforts to reduce carbon dioxide (CO2) and
greenhouse gases (GHG) and other power plant pollut-
ants, global awareness of climate changes, and the ur-
gency to develop renewable energy sources. Other fac-
tors such as lucrative tax incentives and legislation man-
dating national renewable energy standards have acceler-
ated the march towards solar and wind energies. For
example in the US, some states have enacted “renewable
portfolio standard (RPS)” law that requires utilities to
sell a certain percentage of the energy from sustainable
energy sources within reasonable stipulated times. Even
though Europe and North America have the largest in-
stalled capacity of wind turbine capacity, China, India,
and developing world have the biggest potential for wind
power [5].
This paper examines the capacity and potential for
electricity-generating solar- and wind-turbines installed
In the Eastern and Northern part of Jordan. The Jordan
Meteorological Department (JMD) has histological data
on wind speeds and sunshine days in areas of the country
that can be used to assess the potential for solar and wind
energies, and other applications. Jordan has excellent
sunshine covering more than 80% of the country (on the
average of 330-day in a year). The average wind speed in
Jordan is 7 m/s (at 10 meters height above any obstacles
within 100 meters) in some parts of the country. Pres-
ently, the total renewable energy power generation ca-
pacity is about 1% of power generation in Jordan. It is
expected that the share of renewable energy in electrical
power production will be 15% in the future. Wind Solar
alternatives are essential for growth, finance, and the
political environment. The cost of wind power has re-
duced from the cost of power production from US$
0.09.5 per kilowatt-hour to less than US$0.02 for wind
energy production and to US$0.076 cents for solar power
production. This is very significant because developing
countries, which depend on external sources to finance
major energy projects, may be able to finance small scale
solar and wind energies projects from their own re-
G. HALASA ET AL. 73
sources and faster. In this paper the electrical and power
calculations for solar and wind utilization to support the
national grid in Jordan will be analyzed. This paper also
looks at some of the modern power electronics convert-
ers and electrical machines, which have improved sig-
nificantly solar and wind energy technologies to make
them acceptable and embraced as cost effective and re-
newable energy.
2. The Existing Jordan’s National Grid
Jordan is interconnected in one national grid. The grid
covers most of the populated areas of the country from
Aqaba, on the far south to Irbid in the far north. Over-
head transmission line link Syria in the north, Palestine
in the west, while undersea cable links Egypt in the south.
Future countries to be connected to the Jordan national
grid include Lebanon, Iraq and Turkey.
The major generation centers are the Aqaba Thermal
Power Station in the far south, Al-Hussein Thermal
Power Station in Zarka near Amman, and Al-Risha near
the Iraqi border. The Aqaba Power Station uses gas sup-
plied through pipelines from Egypt. The pipeline extends
to Amman. Future expansion of this gas line is expected
to go to Syria and eventually Turkey. Al-Hussein power
station uses fuel oil imported from Iraq. Al-Risha power
station uses locally produced gas. There are several small
units scattered in different districts belonging to older
utilities. These units are used during peak demands.
The oldest and the highest power production plant in
Jordan is the Al-Hussein Thermal Power Station. It is the
most expensive because it uses imported oil and also
uses air-cooling systems, that consume quite amount of
energy, to cool the turbines. A small pilot plant uses
biogas produced by sewerage treatment plant. Another
pilot plant uses wind energy near the sight proposed in
North Jordan. Aqaba Power Station uses Egyptian gas
supplied by gas pipeline. This pipeline already extended
to Amman. Future expansion of this gas line is expected
to go to Syria, and eventually Turkey. Al-Hussein power
station uses fuel oil imported fro Iraq. Al-Risha power
station uses locally produced gas. There are several small
units scattered in different districts belonging to older
utilities. These units are used in peak demands.
3. Conventional Electrical Production Cost
The Kingdom of Jordan is considered an emerging coun-
try in the Middle East; it has almost no natural resources.
The country imports most of its oil needs from neigh-
boring countries at market prices. Oil and gas imports are
huge burden on the country’s national economy. Electric-
ity is generated by burning imported gas and oil, limited
generation from hydro, windmills, and biogas. When oil
prices rose to extremely high levels last summer, Jorda-
nians experienced continuous increases in electricity
prices. It is now urgent and essential to deploy other al-
ternatives for electrical generation, which is the use of
solar and wind energy for electrical generation.
As shown in Table 1, Jordan in 2007 produced a total
of 13,001 GWh of electrical energy and consumed
10,553 GWh. The average per capita electricity con-
sumption in Jordan in 2007 was 2277 kWh as compared
to 2075 kWh in 2006, resulting in annual growth rate of
9.7%. Table 1 shows generating capacity and electrical
energy production by type of generation for 2007.
The state-owned utility National Electric Power Com-
pany (NEPCO) currently carries out almost all electricity
production in Jordan. Al-Hussein Power Plant (with ca-
pacity of 400 MW) and the Aqaba Power Plant (with
capacity of 650 MW) are the country’s two main power
generation facilities.
Jordan has modest reserves of natural gas of 230 bil-
lion cubic feet and has developed one gas field at
Al-Risha in the eastern desert near the Iraqi border. The
current output of this field is around 30 million cubic feet
per day. Al-Risha field is used to fuel one nearby power
plant, which generates about 10% of Jordan’s electricity.
For several years, Jordan has been exploring the option
of importing natural gas from Egypt. In 1999, a decision
was made to delay imports until a more thorough evalua-
tion of reserves at Al-Risha field was completed. When
Table 1. Energy production in 2007 by generation type [6]
Fuel Type
Generating
Plants Capacity
(MW)
Electrical
Production
(GWh)
Steam Units 1013 6,904
Gas Turbines/Diesel 193 45
Gas Turbines/Natural Gas 310 916
Diesel Engines 43 1
Hydro Units 12 61
Windmills 1.4 3
Biogas 4 10
Combined Cycle 600 5,061
Total Generation 2176.4 13,001
Table 2. Fuel consumption in 2007 for electrical generation [6]
Fuel Type Consumption in Thousands Tons Oil Equivalent
Heavy Fuel 621
Natural Gas 2,396
Diesel 9
Total 3,026
Copyright © 2009 SciRes EPE
G. HALASA ET AL.
74
this review showed that quantities available were not
sufficient to meet the country’s needs, Jordan decided to
reopen talks on imports from Egypt. A pipeline was con-
structed and completed in 2006. Aqaba thermal power
station, a major generating center, currently uses Egyp-
tian gas. Jordan imports about 150,000 barrels of oil per
day mostly from Iraq and Saudi Arabia. The Zarka refin-
ery near Amman, the only refinery in the country, refines
the imported oil. Table 2 shows electrical generation fuel
consumption in 2007. Gas and oil imports pose a huge
burden on the national economy. It is evident that the
country is in need for renewable energy projects.
According to 2007 data supplied by NEPCO [6], elec-
trical production cost is US$0.073 per KWh: out of
which fuel cost is US$ 0.0386 per KWh. This figure is
considered expensive as compared to production cost in
other countries. As the oil prices surged to more than
double in the summer of 2008, accordingly the produc-
tion cost increased to US$0.11 per kWh. If it is assumed
that the true value of oil price is $100 per barrel, the
production cost would be about US$0.095 per kWh. This
figure will be used in cost comparison.
4. Assessment of Wind and Solar Energies
In Jordan electricity demand grew at the rate of 9.7% in
2007. The Jordanian government has been seeking ways
to attract foreign capital to fund additional capacity.
Wind and solar energies as main source of electricity
generation are currently set as government priorities. The
government implemented the following actions [7]:
Developing new wind and solar maps for Jordan.
Developing a legal framework for renewable en-
ergy.
Developing incentives for renewable energy pro-
jects.
Securing appropriate funding to implement the first
commercial wind energy project in Jordan.
Secure appropriate funding to implement the feasi-
bility study of the hybrid solar power plant.
Because of the government enthusiasm to promote re-
newable energy, a thorough investigation has been con-
ducted to study the possibility for a hybrid system of
windmills and solar arrays for electricity generation.
Data collected over many years by the JMD [8] has
helped in locating the sights for both windmills and solar
arrays.
The wind farm location was set in the area of Ras-
Munif where the annual wind speed average is 5.5 me-
ters/sec according to data collected by the Meteorologi-
cal Department in Jordan. With the exception of the
months of September and October, where the wind speed
is low, the other 10 months the speed varies from 6 to 6.5
meter/sec. This speed represents the village ground level
speed. If the windmills are sighted at higher elevation
and in the valley curvature between mountains running
west to east where wind tunnel effect exists, the average
wind speed might rise to comfortable levels where
windmills run near full capacity. The windmill tower
height of 100 meters also increases wind speed to levels
close to the 7-9 meter/sec [9], which might bring the
wind turbine power output to 1.0 MW or more. Experi-
ence indicates that wind speed tend to be higher during
the nighttime. Therefore, during the daytime the defi-
ciency in windmills’ power output can be augmented by
solar cells. The average sunshine hours throughout the
year are 8.5 hours per day. In the summer months, May
through September, the average sunshine hours are more
than 10 hours per day. In winter months, November
through February, the average sunshine hours are about 6
hours per day. This means that the solar arrays can sup-
plement the wind turbines daily for 10 hours in the
summer and 6 hours in the winter months. The solar ar-
rays can be scattered between the windmill towers.
5. The Windmill-Solar Hybrid System
5.1. Proposed Windmill-Solar Hybrid
The proposed non-conventional electrical generation
should supply 100-150 MW. As it was pointed out earlier,
the sight is chosen in a high valley curvature in the
mountainous range where wind tunnel effect exists when
continuous high-speed wind prevails all year round. An
array of 100 windmills was chosen for this work. Each
unit has a capacity 1.5 MW. Several windmill suppliers
were investigated and the choice was set on SAIP Elec-
tric Group [10]. Figure 1 shows the windmill chosen for
this project. Since the average annual wind speed char-
acteristics at location is 6 meter/sec and might average
about 8-9 m/sec as was pointed out in Section 5.0 above.
The cut-in wind speed is 3 m/sec, which is way above
the annual average wind speed guaranteeing continuous
Figure 1. The 1.5 MW windmill
Copyright © 2009 SciRes EPE
G. HALASA ET AL. 75
Figure 2. The power-wind speed characteristics
power output. The cutout speed is 25 meter/sec where
this average is over 10 minutes on the average. In that
location wind speeds never reach that high. Figure 2 in-
dicates that the windmill average power output would be
about 1.0 MW for year round.
This power may increase up to 1.5 MW, which is the
maximum power output of the generator. Therefore, the
proposed windmills farm may produce a continuous
power output between 100-150 MW. The blade length is
37.5 m, making the windmill side clearance 75 m, and at
a height of 100 m. Leaving additional side clearance of
100 m so that windmills do not form wind obstacles be-
tween each other. Therefore, the wind farm array farm
should be about 2 km long. Land appropriation for this
sight would be about 200,000 m2.
In case the windmills power output is reduced, solar
cells array may be an alternative for additional support
and reliability. Experience had told us that whenever the
wind speed drops means a fair weather where the sun-
shine is a maximum.
Table 3 shows the solar array type specifications to be
used. The decision was to install solar array to produce
100MW to support the windmill array. A total of 500,000
arrays are needed to supply the required power of 100
MW. The array will be installed in the lower area in the
flat planes.
Table 3. Solar module specifications
Maximum power (Wp) 200W
Maximum power voltage (V) 42
Maximum power current (A) 5.24
Open circuit voltage (V) 50
Short circuit current (A) 5.7
Number of cells (Pcs) 91(7x13)
Size of module (mm) 1702x945x45
Weight per piece (kg) 19
Since Ras-Munif, the location of the windmills is
mountainous area, is also suitable for solar arrays but
limited because it can also be used for agricultural plan-
tations. A better location of the solar modules is in the
Easter Jordanian Desert. In the desert, land is readily
available and the yearly average daily sunshine is 9.3
hours. By installing east-west sun tracing system, a full 8
hours daily average maximum power output can be ob-
tained. Accounting for modules surface area and spaces
between modules, the solar installation requires land
appropriation of 1.0 km2.
Location for the solar power station is chosen to be
near Al-Risha Power Station currently in operation in the
Eastern Jordanian Desert. The sight is chosen for easier
link to the national grid. Al-Risha is located at 32˚ lati-
tude. This requires the modules to be installed inclined
toward the South at 32˚ with the horizontal; facing south-
ward Modules inclination adjustments of ±15˚ are
needed to track the sun’s seasonal variations. East-west
tracking motors may be used to increase full capacity
power production to 9 hours per day.
The proposed hybrid wind-solar installation is needed
to supply Jordan with low cost renewable electric power.
These two installations are capable of supplying 10% of
the country’s electricity peak demand needs for the year
2009.
5.2. Cost Estimation
The cost of one windmill is US$ 1.85 million [10]; addi-
tional 20% of the price may cover shipping and installa-
tion. In addition, US$200,000.00 per unit for controllers
and other supporting equipment may be needed for grid
link. The total cost per unit ready to supply the grid may
be set around US$2.4 million. Another 10% for mainte-
nance, 6% for capital investment, and 5% for administra-
tion to be added to the US$2.4 million; results in net cost
of US$2.9 million per unit. A total of US$290 million are
needed for the wind farm installation to produce
100–150 MW of electrical power. The average lifetime
of the windmill is 20 years. Simple calculations, after the
assumption that the full wind power output is for 20
hours per day, result in electrical production cost of
US$0.02/kWh.
As for the solar power station, the cost of 500,000
modules needed to produce 100 MW is US$370 million.
This cost includes the controllers for the ground link. In
addition to the US$370 million solar modules cost, 20%
for installation, 10% for the sun tracking, 6% capital in-
vestment, and 5% for administration, bringing the total
cost for the solar power station to US$560 million. The
high percentage for installation is to cover the cost of
frames upon which the modules will be installed. Re-
membering that the power production is for 8 hours per
day and the lifetime of the solar cells is 25 years; the
production cost will be US$0.077/kWh. This production
Copyright © 2009 SciRes EPE
G. HALASA ET AL.
Copyright © 2009 SciRes EPE
76
cost is almost the same as the present conventional cost
but lower than the projected cost of US$0.09/kWh when
the price of oil reaches US$100 per barrel.
Comparing the wind and solar power production costs,
it seems that wind power production cost is lower than
the solar power production. Therefore, wind energy pro-
duction is feasible now even with oil prices at US$40 per
barrel. In the future when oil prices rise, even with the
high cost of solar energy, solar power is important for
power floe reliability.
6. Ras-Munif – Village of ‘Ebelin Hybrid
Power Project
Ras-Munif, located in the province of Ajloun, is one of
the highest mountains in Jordan: about 1198 m above sea
level. The villages of ‘Ebelin are also located in the
province of Ajloun and 4.9 km from the city center of
Ajloun, directly below Ras-Munif, see Figure 3. Land
terrain, wind characteristics, solar sunshine days, and
politics are considered important issues for the location
of wind and solar farms. It is clear that the wind speed
and sunshine days data mined by JMD make Ras-Munif
an ideal location for wind and solar farms.
6.1. Wind Energy
Wind energy depends mostly on wind speed and kinetic
energy of the air mass even though wind speed is also
affected by air density, air temperature, air barometric
pressure, altitude, and local terrain. Wind generators are
practical where the average wind speed is greater than
4.5 m/s and with constant flow rate at minimum turbu-
lence and minimum powerful wind bursts. The Figure 4
shows best wind turbine locations on mountainous ter-
rain.
JMD has kept data of wind speeds and directions at
different locations in Jordan; wind speed and direction
are very important factors for location of wind farms.
Ras-Munif, one of highest mountains in Jordan, is very
rich in wind speeds with an average wind speed of 5.5
m/s reaching a maximum value of 6.37 m/s during winter.
Ras-Munif
‘Ebelin
Figure 3. Area view of Ras Munif and ‘Ebelin
Site 1:
Ideal – Wind is in all directions
Site 2:
Poor – Wind direction is poor
Site 3:
Good – Wind in two directions
Figure 4. Terrain location of wind turbines
G. HALASA ET AL. 77
Table 4. Kyocera (kc130gt) solar panel rating
Price
Per Panel 431.87JD Short Circuit
Current 8.02 A
Rated
Power 130 W Area of
Panel 0.929 m2
Rated
Voltage 17.6 V At 70%
Peak Load 5385
Rated
Current 7.39 A Cells Per
Panel
36 Polycrystalline
Cells
Open Cir-
cuit Voltage 21.1 V Cost Per KW US$4681.34/KW
6.2. Solar Energy
Solar energy depends on the amount of direct sunlight
even though clouds, blue patches, shades, and rain also
affect direct sunlight. Solar panels are located at areas
with best sun exposure. Solar panels are practical where
the average sunshine is greater than 5 hours a day. The
solar panels must be kept cool with minimum clouds
(equivalent to approximately 50% peak sun), minimum
blue patches and shades (shading even one cell of the
panels can reduce the output of an entire array), and less
rain (equivalent to approximately 20% peak sun).
JMD has kept data on sunshine hours at different loca-
tions in Jordan. Ras-Munif is very rich in sunshine due to
its elevation [7–8] with average sunshine of 8.5 hours per
day and reaching a maximum of 12.3 hours/day during
summer.
6.3. Hybrid Power System
In addition to the present conventional power system, the
hybrid power system of Ras-Munif consists of solar
panel arrays and generators; the hybrid system is tied in
to the conventional system. The output voltage of the
solar arrays and the wind generators are tied and syn-
chronized together with the conventional power system
main bus at the same potential. The voltage at the main
bus is kept constant and used to supply the load. The
Figure 5 [7–8] shows the location of the hybrid power
generation system located at Ras-Munif, and transmis-
sion lines from Ras-Munif to ‘Ebelin villages. The power
produced at ‘Ebelin is at 230 V. The solar panel selected
and built into the solar arrays, is the low cost Kyocera
module KC130GT with rating shown in Table 4.
The solar panels are connected in two format arrays –
serial and parallel. The solar panels are connected in se-
ries to meet the voltage requirements and in parallel to
meet the current requirements. The output of the arrays
has a DC/DC converter linkage integrated into volt-
age-source-inverter (VSI) system to hold the voltage at
constant value. The solar panels have sun trackers for
adjusting the panel tilts during winter and summer ac-
cording to the following equations [7–8]:
Summer Tilt = Location Latitude – 15˚ (1)
Winter Tilt = Location Latitude + 15˚ (2)
The Ras-Munif site selected has “Location Latitude”
of 32˚ with the horizontal facing south.
All the wind generator turbines are the horizontal axis
wind turbine types because they are low cost and easy to
maintain. The smallest wind generator is rated at least 10
KW. The characteristics of a typical generator are shown
in Table 5.
Location of
system
Transmission
Line Path
‘Ebelin
Figure 5. Location of hybrid power system and transmission line path
Copyright © 2009 SciRes EPE
G. HALASA ET AL.
78
Table 5. Typical wind turbine characteristics
Power
Rating >10 KW Blade Material Fiberglass-reinforced
Epoxy
Rated
Wind Speed 13 m/s Yaw Control Passive Aligned
by Tail vane
Cut-in
Wind Speed 3 m/s Rate RPM 25 - 300
Rotor
Diameter > 7 m Tower Height 12 – 40 m
Number of
Blades 3 Weight Minimum 7540 kg
Collection of
Windmills
or
Solar Arra
y
Vo l ta g e
Regulation
Transformer
To
Grid Voltage Grid Bus
Figure 6. Proposed power system
er Electronics
Requirements
tegrated
mber of power
co
been used to ex-
tra
7. Pow
7.1. Electrical and Power
The solar- and wind-energy systems must be in
into the national grid. A block diagram of the proposed is
shown in the block diagram of Figure 6.
Papers [11–20] have presented a nu
nverter topologies for wind generators for wind energy
conversion systems. There are various power electronic
converters that have been developed.
Power Electronics converters have
ct the maximum power and to allow for variable speed
operation of wind turbines. In this project the power
electronics converter selected has the following proper-
ties: 1) the maximum power obtained from control sys-
tem of the converter is compared with the maximum
power point tracking (MPPT) curve [18–21] at wind
speeds/sun shine levels, 2) the converter must provide
the required residential/commercial voltage, 3) the con-
verter must provide frequency to within the specified
error, and 4) the efficiency for small scale power must be
met. A permanent magnetic synchronous generator
(PMSG) and a supply-side voltage source inverter (VSI)
are selected for the wind-energy for lower cost and
higher power output. The DC/DC–VSI combination is
capable of handling weak sun AC systems. There are
various control strategies for the VSIs including d-axis
and q-axis PI controllers and use of space vector modu-
lation (SVM) to achieve a better modulation index. Even
though PMSGs have initial higher cost (price of magnets)
and may be demagnetized (high temperatures, overload-
ing, and short circuits), they are flexible, have high out-
put power without the need to increase size of generator,
have lower maintenance costs (no carbon brushes, bear-
ings, etc.), have lower losses, have very high torque at
low speeds, are self-exciting machines, and do not need
cooling systems. A major advantage of using PMSG is
that they do not require external excitation and simple
diode rectifier circuit may be used at the generator ter-
minals. Figure 7 shows the block diagram of the solar-
and wind-energy system.
The solar system includes a boost converter for the
MPPT. A DC/DC converter linkage is integrated into the
VSI and solar systems 1) to control the generator-side
DC-generator for both the solar and wind systems, 2) to
maintain the desired DC-voltage for the inverter-side, 3)
to eliminate certain harmonics, and 4) to provide more
flexible control. The wind-generator output power is
maximized using MPPT control systems and algorithms.
The p-q theory [22] is used to control the active and re-
active power, and the power factor.
PMS
G
GRID
DC LIN
K
VS
I
DC-DC
TIE
p-q
Compensator
Figure 7. Hybrid solar- and wind-energy power system
Copyright © 2009 SciRes EPE
G. HALASA ET AL. 79
Measured Voltage
and Current Values
Calculate Power Pin
,
k
P
in,k > Pin,k-1?
Controller Algorithm
Control Commands
Measurement
Data Acquisition
STA
Win
Figure 8. MPPT control algorithm process
The MPPT can be used to achieve optimal operatio
sions
ctric production cost that is directly
on. The cost of the solar power
[1] N. Kodama, T. Matzuzaka, and N. Inomita, “power varia-
ind turbine using probabilistic optimal
feed-forward control for wind speed,”
troulis and K. Klaitzakis, “Design of a maximum
Re-
. Hennessey Jr., “On the use of
. Knight, “A re-
–238,
ion, Transmission, and Distribution, Vol.
150, pp. 447–454, July 2003.
n
V
mode of the solar-and wind-generator power conversion
system. The MPPT does not require knowledge of opti-
mal power characteristics or measurement of wind speed,
does not depend on the rotor-speed rating of the
wind-generator, and does not depend on the power rating
of the DC-DC converter. The required voltage and cur-
rent signals are measured using sensors such as Hall Ef-
fect or linear electro-magnetic (LEM) sensors through
analog-to-digital (ADC) converters.
The Figure 8 shows a generic representative flowchart
of an MPPT control algorithm. In the flowchart the
MPPT battery system is not taken into consideration. The
error signals are obtained by comparing the reference
control signals and corresponding measured values.
The MPPT algorithm is then applied to the error sig-
nals. The duty-cycle ratio change command is then im-
plemented.
8. Conclu
Jordan has high ele
linked with oil prices. An alternative is renewable wind
and solar electric power production. The possibility was
thoroughly investigated. The result is to install windmill
farm in the mountainous area in the north, where wind
speed proved to be viable, while the eastern desert is
suitable to install solar power station. The cost for the
windmill farm to produce 100 – 150 MW for 20 hours
station to produce 100 MW for 8 hours per day is
US$560 million. The production cost is US$0.02/kWh
for the windmill and US$0.077/kWh for the solar. The
conventional production cost is US$0.095/kWh projected
when the price of oil is US$100 per barrel. For reliable
energy system, hybrid power production is essential.
The features of the generator-converter are considered
to meet the requirements for the wind and solar systems.
The solar- and wind-generator power outputs can be
m
per day is US$290 milli
aximized using MPPT control systems and algorithms.
The p-q theory is used to control the active and reactive
power, and the power factor.
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