To design solar (photovoltaic) - Wind hybrid power generation system by editorijettcs


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									    International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: Email:,
Volume 1, Issue 4, November – December 2012                                    ISSN 2278-6856

        To design solar (photovoltaic) - Wind hybrid
                 power generation system
                                              Chitesh Dubey1, Yogesh Tiwari2
                                 ME Scholar, Department Of Electrical Engg., SSCET Bhilai, India
                                         Asso. Prof., EEE Department, SSCET Bhilai, India

Abstract: In recent year’s generation of electricity using the    conditions. For example, during cloudy periods and at
different types of renewable sources are specifically evaluated   night, a PV system would not generate any power. In
in the economical performance of the overall equipment.           addition, it is difficult to store the power generated by a
Solar power & wind power has received considerable                PV system for future use. To overcome this problem, a
attention worldwide. The presented methodology is applied to      PV system can be integrated with other alternate power
evaluate the potential of Solar (photovoltaic) –wind hybrid       sources and/or storage systems, such as electrolyses,
system to produce electricity for a community and other state.
                                                                  hydrogen storage tank, Fuel Cell systems. Combined
Through this hybrid system we have reduce pollution and
decrease the global warming. In this we have analyzing the
                                                                  wind and solar systems are becoming more popular for
data of wind and solar energy and evaluate the average            stand–alone power generation applications, due to
energy by using hybrid system we have fulfills the energy         advances in renewable energy technologies and
demand into the future. In future by using of better quality      subsequent rise in prices of petroleum products. The
sensor be can increase the potential. We use the small storage    Economic aspects of these technologies show sufficient
capacity. Because maintained cost becomes low using the           promise to include them in developing power generation
better quality data logger is can increase the energy             capacity for developing countries. Research and
production. In future we have to install large solar and wind     development efforts in solar, wind, and other renewable
plant which are cheaper as compared to small plants. The          energy technologies are required to continue improving
Modeling and simulation of the Solar (photovoltaic) –wind         their performance, establishing techniques for accurately
hybrid system is carried out using MATLAB/SIMULINK.
                                                                  predicting their output and reliably integrating them with
Keyword: wind           power,       solar   power,   battery,    other conventional generating sources [6].

                                                                  2. MODELING THE COMPONENTS OF A
Renewable Energy Sources are those energy sources                 HYBRID POWER SYSTEM
which are not destroyed when their energy is harnessed.           2.1Modeling the Solar (PV) System
Human use of renewable energy requires technologies               A PV generator consists of an assembly of solar cells,
that harness natural phenomena, such as sunlight, wind,           connections, protective parts, supports etc. Solar cells are
waves, water flow, and biological processes such as               made of semiconductor materials (usually silicon), which
anaerobic digestion, biological hydrogen production and           are specially treated to form an electric field, positive on
geothermal heat. Amongst the above mentioned sources              one side (backside) and negative on the other (towards
of energy there has been a lot of development in the              the sun). Then solar energy (photons) hits the solar
technology for harnessing energy from the Solar & wind            cell, electrons are knocked loose from the atoms in the
[6].                                                              semiconductor material, creating electron-hole pairs. If
Solar and wind energy are non-deflectable, site-                  electrical conductors are then attacked to the positive
dependent, non-polluting, and potential sources of                and negative sides, forming an electrical circuit, the
alternative energy options. Many countries are pursuing           electrons are captured in the form of electric current
the option of wind energy conversion systems; in an               (photocurrent) [4].The model of the solar cell can be
effort to minimize their dependence on fossil-based non-          realized by an equivalent circuit that consists of a current
renewable fuels. Also, presently thousands of                     source in parallel with a diode (Fig.1).
photovoltaic (PV) deployments exist worldwide,
providing power to small, remote, grid-independent or
stand-alone applications. For both systems, variations in
meteorological conditions (solar irradiation and average
annual wind conditions) are important. The performance
of solar and wind energy systems are strongly dependent
on the climatic conditions at the location. The power
generated by a PV system is highly dependent on weather               Figure 1 Equivalent circuit diagram of a solar cell

Volume 1, Issue 4 November - December 2012                                                                         Page 101
      International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: Email:,
Volume 1, Issue 4, November – December 2012                                    ISSN 2278-6856

The p-n junction has a certain depletion layer                 radiation. This is done by using standard Simulink and
capacitance, which is typically neglected for modeling         Matlab modules and functions. This block allows
solar cells.At increased inverse voltage the depletion         selecting different type of patterns for the solar radiation.
layer becomes wider so that the capacitance is reduced         The PV module implements the equivalent circuit of a
similar to stretching the electrodes of a plate capacitor.     solar cell, shown in Fig.1. Standard functions and blocks
Thus solar cells represent variable capacitance whose          of Matlab and Simulink were used to obtain this model.
magnitude depends on the present voltage. This effect is       Its structure is presented in Fig 3.The output of the PV
considered by the capacitor C located in parallel to the       module is processed by an energy conversion block
diode [4].                                                     implemented with a PWM IGBT inverter block from
Series resistance RS consists of the contact resistance of     standard Simulink/Sim-Power Systems library [1].
the cables as well as of the resistance of the
semiconductor material itself. Parallel or shunt resistance
RP includes the “leakage currents” at the photovoltaic
cell edges at which the ideal shunt reaction of the p-n
junction may be reduced. This is usually within the kΩ
region and consequently has almost no effect on the
current-voltage characteristic [1].
The diode is the one which determines the current-
voltage characteristic of the cell. The output of the
current source is directly proportional to the light falling
on the cell. The open circuit voltage increases
logarithmically according to the Shockley equation which
describes the interdependence of current and voltage in          Figure 3 Matlab Simulink implementation of the PV
a solar cell [1].                                                                    module

                                                               2.2 Modeling the Wind Energy System
                                                               Modeling the wind energy converter is made considering
                                                               the following assumptions
                                                               - Friction is neglected;
(2)                                                            - Stationary wind flow;
Where:                                                         - Constant, shear-free wind flow;
 k - Boltzmann constant (1.3806 10-23 J/K);                    - Rotation-free flow;
T - Reference temperature of solar cell;                       - Incompressible flow (q=1.22 kg/m3);
q - Elementary charge (1.6021 10-19 As);                        - Free wind flow around the wind energy converter
V - Solar cell voltage (V);                                    On the above condition the maximum physical
I0 - saturation current of the diode (A);                      achievable wind energy conversion can be derived using
IPV - Photovoltaic current (A).                                a theoretical model that is independent of the technical
Equations (1) and (2) lead to the development of a             construction of a wind energy converter [1].
Matlab Simulink model for the PV module presented              The flow air mass has certain energy. This energy is
in Fig. 2.                                                     obtained from the air movement on the earth’s surface
                                                               determined by the difference in speed and pressure. This
                                                               is the main source of energy used by the wind turbines
                                                               to obtain electric power [7].
                                                               Wind energy systems harness the kinetic energy of
                                                               wind and convert it into electrical energy or use it to
                                                               do other work, such as pump water, grind grains, etc.
                                                               The k inetic energy of air of mass m moving at speed
                                                               v can be expressed as
                                                               During time period t, the mass (m) of air through a given
                                                               area A at speed v is:
      Figure 2 Matlab Simulink Library PV module.
The solar system model consists of three Simulink
                                                               Where ρ is the density of air (kg/m3).
blocks: the solar model b l o c k , the PV model block
and energy conversion modules. The solar model block           Based on the above two equations, the wind power is
implements the mathematical model of the solar

Volume 1, Issue 4 November - December 2012                                                                      Page 102
      International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: Email:,
Volume 1, Issue 4, November – December 2012                                    ISSN 2278-6856

                                                                                                        The Wind Turbine Induction Generator model is much of
(5)                                                                                                     complicated part of whole simulation model. It consists
The specific power or power density of a wind site is                                                   of Induction Generator & Wind Turbine. Wind Turbine
given as                                                                                                shown in fig.5. The three inputs are the generator speed
                                                                                                        (ωr_pu) in pu of the nominal speed of the generator, the
                                                                                                        pitch angle in degrees and the wind speed in m/s. The tip
(6)                                                                                                     speed ratio λ in pu of λ_nom is obtained by the division
(a) Power Extracted from Wind.                                                                          of the rational speed in pu of the base rotational speed
From wind is the difference between the upstream and                                                    (defined below) and the wind speed in pu of the base
the down-stream wind powers [7]                                                                         wind speed. The output is the torque applied to the
                      )                                                                                 generator shaft.
                                                                                                                                     wind_speed_pu                                                                                     Pwin d_pu
                                                                                                               3            -K-                                                         u(1)^3
Where v is the upstream wind velocity at the                                                               Wind speed
                                                                                                                                  wind_speed_pu                                                      Pwind_pu                                                     Pm_pu
entrance of the rotor blades, v0 is the downstream                                                            (m/s) 1/wind_base                                                    wind_speed^3
                                                                                                                                   Avoid division                                                                                                                         pu->pu

wind velocity at the exit of the rotor blades. Hm is the                                                                                 by zero
mass flow rate, which can be expressed as
                                                                                                                                                                             -K-                                lambda
                  )                                                                                                1                    -K-                    lambda_pu           lambda
                                                                                                                                                                                    lambda                                      cp    -K-
                                                                                                          Generator speed (pu)                       Product               lambda_nom                           beta
                                                                                                                                                                                                                                     1/c p_nom
                                                                                                                                                                                                                 cp(l ambda,beta )
 (8)                                                                                                                                                                                             2
                                                                                                                                                                                         Pitch angle (deg)

Where A is the area swept by the rotor blades.
                                                                                                                                                                                                                                                                                     -1     1
From (7) and (8), the mechanical power extracted by the                                                                                                                                                                                                                                   Tm (pu)
                                                                                                                                                                Avoid division
rotor is given by:                                                                                                                                                 by zero

                                                                                                          Figure 4 the Matlab/Simulink implementation of the
(9)                                                                                                                          wind turbine.
                                                                                                        2.3 Modeling the Storage Device
(10)                                                                                                    Batteries are the basic component of an energy storage
 We have                                                                                                system. A battery consists of one or more electrochemical
                                                                                                        cells that are electrically connected. The basic
(11)                                                                                                    components of an electrolytic cell like a lead-acid cell are
                                                                                                        a positive electrode, a negative electrode, a porous
 Cp is called the power coefficient of the rotor or the rotor                                           separator and an electrolyte. During cell operation, ions
efficiency. It is the fraction of the upstream wind power,                                              are created and consumed at the two electrode/electrolyte
which is captured by the rotor blades and has a theoretical                                             interfaces by oxidation/reductions reactions.           The
maximum value of 0.59. In practical designs, maximum                                                    electrolyte, which cans either, be a solid or liquid
achievable Cp is between 0.4 and 0.5 for high-speed, two-                                               chemical, has high conductivity for ions but not for
blade turbines and between 0.2 and 0.4 for low-speed                                                    electrons, because if the electrolyte conducts electrons
turbines with more blades.[7] A Matlab Simulink model,                                                  then the battery will self-discharge. The electrolyte
based on the equations mentioned above, was developed                                                   completes the internal circuit between the electrodes. In
for the wind generator module. This model is shown in                                                   figure 4.5 the Thevenin equivalent battery model is
Figure 4.                                                                                               presented [2].

                          -   v

                 V ol tage M easurem ent


       1                              A
  Con n1
      2                               B                             <Rot or s peed (wm)>
  Con n3n2
    Con                               C

                                    Wind Turbine

                                    Ge n e ra to r sp e e d ( pu)                          Co nsta nt

                          T m (p u)         P itch a ngle (d e g)                              2

                                           W in d spe e d (m / s)

                                            Win d
                                                                                                                         Figure 6 Thevenin equivalent battery model.

                                                                                                        The open circuit voltage, internal capacitor voltage and
Figure 4 The Matlab Simulink model of the wind turbine                                                  the terminal voltage are represented by VO, VP and
             Induction generator module.                                                                Va . The charging, discharging and the internal

Volume 1, Issue 4 November - December 2012                                                                                                                                                                                                                                         Page 103
                International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: Email:,
Volume 1, Issue 4, November – December 2012                                    ISSN 2278-6856

resistance of the battery are represented by Rc, R d and                                                                                                                                                                                                                         3. RESULT
Rb and the polarization capacitance of the battery is                                                                                                                                                                                                                            For the simulation, the data solar irradiance, temperature
represented by C. The current Ia is taken as positive if                                                                                                                                                                                                                         and wind speed are used. The three data will be the input
discharging and negative otherwise [2].                                                                                                                                                                                                                                          of the PV and Wind energy generation system. Figure’s
                                                                                                                                                                                                                                                                                 shown below show the waveform of the output of the solar
The equation for the circuit model is:                                                                                                                                                                                                                                           and wind energy generation system.
                        ]                                                                                                                                                                                                                                                                                                     1.95
                                                                                                                                                                                                                                                                                                                                            x 10                                    Time Series Plot:

(12)                                                                                                                                                                                                                                                                                                                          1.94


                                                                                                                                                                                                                                                                                    s o la rp o w e r( W )

Based on this model and the equations above, a Matlab-                                                                                                                                                                                                                                                                        1.91

Simulink model was developed for the battery storage                                                                                                                                                                                                                                                                               1.9
device. This model is shown in Figure 4.6.

                                                                                                                                                                      +                                                   +                                 1                                                                 1.88
                                           Series RLC Branch                                                                                                                                                              - v                                                                                                               0             0.1     0.2   0.3   0.4         0.5           0.6   0.7    0.8      0.9               1
                                                                                         Diode                                                                    Series RLC Branch2                                                                    volt                                                                                                                        Time (seconds)
                                                                                                                                                                                  Voltage Measurement

                                                                                                                                                                                                                                                                                                                                                                 Figure 9 waveform of solar power
                                                                                                                                                                                                                                                                                                                                                                                    Time Series Plot:

                                            +                                                                                                                                                                                                                                                                                 250

                                       Series RLC Branch1
                                                                                                                        +                                                                                                                                                                                                     200
                                                                                                                                                                                                                                                                                   s o la r v o lt a g e (V )

                                                                                                                    Series RLC Branch3
                            Controlled Voltage Source

                 1     In1


   Figure 7 The Matlab Simulink model of the battery                                                                                                                                                                                                                                                                                     0                0.1     0.2   0.3   0.4         0.5
                                                                                                                                                                                                                                                                                                                                                                                    Time (seconds)
                                                                                                                                                                                                                                                                                                                                                                                                        0.6   0.7    0.8      0.9               1

                   storage device.                                                                                                                                                                                                                                                                                                                              Figure 10 waveform of solar voltage
2.4 Solar-Wind Hybrid Power System
                                                                                                                                                                                                                                                                                                                                                                                    Time Series Plot:
Using the RegenSim. Library a renewable energy hybrid
system shown in Fig.8 . had developed. As shown, the                                                                                                                                                                                                                                                                               300

simulation system contains power generation blocks                                                                                                                                                                                                                                                                                 200

from renewable energy sources such as sun, wind,                                                                                                                                                                                                                                                                                   100
                                                                                                                                                                                                                                                                                 w in d v o lt a g e (V )

battery blocks (providing the        energy   storage),                                                                                                                                                                                                                                                                                 0
measurements      blocks    for electrical  parameters
(voltage,   current etc), inverter blocks (for power
generation in DC voltage), energy consumer block.                                                                                                                                                                                                                                                                        -200

                                                Measur ements     Te rminator
                                                                                     SPin              Sc urrent
                                                Power at Load
    Radiation        Solar Radiation
                                                            +                        +                     SPot                                                      Solar Curren t                                                                                                                                      -400
                                                                                                                                                                                                                                                                                                                                            0             0.1     0.2   0.3   0.4         0.5           0.6   0.7    0.8      0.9               1
Sola r Model                 Photo voltaic (PV) Model
                                                                                     -                     SV olt                                   Solar power                                                                                                                                                                                                                     Time (seconds)
                                                                                            Mesuremen t1
                                                                                                                              sol ar Volt                                                    Discrete
                                                                                                                                                                                           PWM Generator
                                                                                                                                                                                             6 pulses
                                                                                                                                                                                                                                                                                                                                                        Figure 11waveform of generated wind voltage.

                                                                                                                                             Controlled                                                  -              Vab inv erter
                                                                                                                                            volt. source

                                                                                                                                                                                      g                                                                                                                                                         6                                   Time Series Plot:
                                                                                                                                                                                                                                                                                                                                        x 10
                                                                                                                                                                                      A             A               a
                                                                                                                       In1             v olt
                                                                                                                                                                                                                                                                                                                                                                                                                                    Active power
                                                                                                                                                                                      B             B               b
                                                                                                                                                                     -                                                                                                                                                                                                                                                              Reactive power
                                                                                                                                                                                   C                C               c
                                                                                                                                                                     Un iversal Bridge             23 0V /230V 2MVA
                                                                                                                                                                          3 arms                       Transform er
                                                                                                                                                                                                                                                                                     w in d a c t iv e & re a c t iv e p o w e r


                                   Conn1                          A             a                                                                                                                                                                                                                                                  1
                                   Conn2                          B             b

                                   Conn3                          C             c
                                                                230V /230V 2M VA
                                                                  Tra nsfo rmer1
                                                                                                                                                                                                                                                                       Scop e3
                                            powergui                                                                                                                                                                                                +


                                                                                                                                                                                                                                            3-phase lo ad                                                                          -2

                                                                                                                                                                                                                                                                                                                                        0                0.1     0.2    0.3   0.4          0.5          0.6    0.7    0.8       0.9                  1
                                                                                                                                                                                                                                                                                                                                                                                     Time (seconds)

 Figure 8 The Matlab Simulink model of the solar-wind
                                                                                                                                                                                                                                                                                                                                        Figure 12 waveform of the active and reactive power.
           hybrid power generation system.

Volume 1, Issue 4 November - December 2012                                                                                                                                                                                                                                                                                                                                                                                  Page 104
                                 International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: Email:,
Volume 1, Issue 4, November – December 2012                                    ISSN 2278-6856

                                                                                                                            techniques of automatic control and computer
                                                            Time Series Plot:Vab inverter
                                                                                                                            engineering IJ-STA Vol. 2 No.2 pp 722-727 Dec.
                                                                                                                          [4]. Shishir Kumar Pradhan,           “Modeling and
                                                                                                                            Simulation of PV array with boost converter: An
                                                                                                                            open Loop Study” A thesis presented for the Bachelor
V a b in v e rt e r

                                                                                                                            of Technology Degree Department Of Electrical
                                                                                                                            Engineering National Institute Of Technology
                                                                                                                          [5]. Jinhong Jeon, “Development of A Grid Connected
                                                                                                                            wind/PV/BESS Hybrid Distributed Generation
                                                                                                                            System.” 19th International Conference on Electricity
                            0       0.1   0.2   0.3   0.4               0.5                 0.6   0.7   0.8   0.9   1
                                                                  Time (seconds)

                                  Figure 13 waveform of Inverter output voltage                                             Distribution Vienna 21-24 May 2007 paper 0539
                                                                                                                          [6]. Shalikram Dewangan, “stability enhancement of a
                                                             Time Series Plot:Vab_load                                      wind energy embedded distribution system” A thesis
                                                                                                                            presented for the Master of Engineering Degree
                      200                                                                                                   Department Of Electrical Engineering SSCET
                                                                                                                            Junwani Bhilai
                                                                                                                          [7]. G.D. Rai, “A book of Non conventional energy
V a b _ lo a d

                        0                                                                                                   sources”


                                                                                                                                     Chitesh Dubey received the B.E degrees in
                             0      0.1   0.2   0.3   0.4                0.5
                                                                   Time (seconds)
                                                                                            0.6   0.7   0.8   0.9   1               Electrical & Electronics Engineering from SSCET,
                                                                                                                                    Bhilai in 2007 and Pursing M.E. Degree in Power
                                      Figure 14 Waveform of the load voltage.                                                       System Engineering from SSCET, Bhilai. During
                                                                                                                                    2008, he joined as Lecturer in EEE department of
4. CONCLUSION                                                                                                           CIT Rajnandgaon.
The capitalization of renewable resources potential
confers real premises to achieve some strategic aims, but                                                                              Yogesh Tiwari is currently worked as an Asso.
                                                                                                                                       Prof. in EEE Department of SSCET Bhilai. He
also the durable development of energy sector and the
                                                                                                                                       received the B.E degrees in Electrical
protection of the environment. In order to exploit the
                                                                                                                                       Engineering from BIT, Durg in 1997 and
economic potential of renewable resources in competitive                                                                               M.Tech. Degree in Instrument & Control
conditions on the energy market, it is necessary to adopt                                                                              Engineering from BIT, Durg in 2006. Pursuing
and implement some energy policies and specific                                                                         PhD in Electrical Engineering from C.V. Raman University
resources. The promotion of energy production from                                                                      Bilaspur. He has over 4 year industrial & 10 year teaching
renewable resources represents an imperative objective in                                                               experience. He has published near 15 research papers in
present times justified by environment protection, the                                                                  national & international conferences & journals.
increase of energetic independence by supplying sources
diversity and, of course, economic and social cohesion

                        [1]. Dorin Bica, Cristian Dragoç Dumitru, Adrian,
                          “Isolated hybrid solar–wind-hydro renewable
                          energy systems.” Scientific bulletin of the Petru
                          Maior University of the Targu Mures Vol.7
                          (XXIV),No.2 2010 ISSN 1841-9267
                        [2]. Basker Vairamohan,“ State of Charge Estimation
                          Of Batteries.” A thesis presented for the Master of
                          Science Degree, The University of Tennessee,
                        [3]. M. N. Mansouri Ecole, M. Mansouri Ecole,
                          M.F.Mimouni Ecole, “modeling and c o n t r o l
                          energy management of a hybrid system associated a
                          continuous load and coupled with the electrical
                          network.” International journal of sciences and
Volume 1, Issue 4 November - December 2012                                                                                                                               Page 105

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