Modeling And Simulation Of Solar Photovoltaic System - IJTSRD

International Journal of Trend in ScientificResearch and Development (IJTSRD)International Open Access JournalISSN No: 2456 - 6470 www.ijtsrd.com Volume - 1 Issue – 6Modeling and Simulation of Solar Photovoltaic SystemIrfan KhanStudent of M.Tech Power System, MTPS-13-29 ,Department of Electrical & ElectronicsEngineering, AL- Falah University, Faridabad,Haryana, IndiaAmeen Uddin AhmadAssistant Professor, Department of Electrical &Electronics Engineering, AL- Falah University,Faridabad, Haryana, IndiaABSTRACTSolar energy is a vital untapped resource in a tropicalcountry like ours. The main hindrance for thepenetration and reach of solar PV systems is their lowefficiency and high capital cost. The efficiency ofsolar PV is very low. In order to increase theefficiency, Maximum Power Point Tracking (MPPT)techniques are to be undertaken to match the sourceand load property. These techniques are employed inPV systems to make full utilization of PV array outputpower. Recently, many MPPT algorithms of PVsystem have been proposed which depends on solarirradiation and temperature, but perturb and observe(P&O) and Incremental conductance algorithms arebasic and most widely used. This project firstlyintroduces a Mat lab Simulink of photovoltaic array.To achieve the maximum power point tracking theIncremental Conductance method and perturb andobserved (P&O) method are used. These twoalgorithms are employed with PV model along withconverter in Mat lab Simulink. Three differentconverter boost, buck boost and cuk converter aredesign according to requirement and used. Fewcomparisons such as voltage, current and poweroutput for each different combination have beenrecorded.Keywords: Perturb and Observe, IncrementalConductance, Maximum Power Point Tracking,energy storage systemINTRODUCTIONtimes over. It doesn’t give out CO2 emissions. Itwon’t run out & its free.Temperature and Irradiation are the major hindrancesin exploitation of solar cell efficiency andconsequently the need for Algorithm arises for gettingthe maximum power output from the solar cell. Andhence PV power control is one of the burning researchfields these days.There are different techniques for MPPT such l conductance, Fractional ShortCircuit Current, Fractional Open Circuit Voltage,Fuzzy Control, Neural Network Control etc. Amongall the methods Perturb and observe (P&O) andIncremental conductance are most commonly usedbecause of their simple implementation, lesser time totrack the MPP and several other economic reasons.Under abruptly changing weather conditions(irradiance level) as MPP changes continuously, P&Otakes it as a change in MPP due to perturbation ratherthan that of irradiance and sometimes ends up incalculating wrong MPP. However this problem getsavoided in Incremental Conductance method as thealgorithm takes two samples of voltage and current tocalculate MPP. However, instead of higher efficiencythe complexity of the algorithm is very high comparedto the previous one and hence the cost ofimplementation increases. So we have to mitigatewith a tradeoff between complexity and efficiency.The Sun-that Power Plant in the Sky-bathes Earth inAmple of Energy to fulfill world’s power needs many@ IJTSRD Available Online @ www.ijtsrd.com Volume – 1 Issue – 6 Sep - Oct 2017Page: 1276

International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-64701.MODELINGOFPHOTOVOLTAIC SYSTEMSOLARSolar Photovoltaic (SPV) System: The process ofconverting light (photons) to electricity (voltage) iscalled the photovoltaic (PV) effect. A photovoltaic(PV) system directly converts sunlight into electricity.The basic device of a PV system is the photovoltaic(PV) cell. A PV cell typically produces voltage 0.5volt. In order to increase the voltage cells areconnected in series and to increase the current theyare connected in parallel. The photovoltaic module isthe result of associating a group of PV cells in seriesand parallel and it represents the conversion unit inthis generation system. An array is the result ofassociating a group of photovoltaic modules in seriesand parallel.Equivalent Circuit of PV Cell: The equivalentcircuit, which describes the static behavior of the solarcell, is commonly composed of a current source, a pnjunction diode and a shunt resistor (Rsh) in parallelalong with a series resistor (Rs). Thecurrent sourcemodels electron injection from light. Rs is the totalOhmic resistance of the solar cell, which is essentiallythe bulk resistance. Smaller Rs values equate toincreased solar cell efficiencies. Rsh accounts forstray currents, such as recombination currents andleakage currents around the edge of devices. In thiscase a larger Rsh value equates to increased solar cellefficiency, since it means that the stray currents arereduced.RLOADFig.-2 PV module with dc-dc converterDC/DC converters are used in applications where anaverage output voltage is required, which can behigher or lower than the input voltage. To maximizethe power output of the PV system, a high-efficiency,low-cost DC/DC converter with an appropriatemaximum power point tracking (MPPT) algorithm iscommonly employed to control the terminal voltageof the PV system at optimal values in various solarirradiation conditions. A dc to dc converter whichinterface between load and module, serve the purposeof transferring maximum power from PV module tothe load. By changing the duty cycle the loadimpedance as seen by the source is varied andmatched at the point of the peak power with thesource so as to transfer the maximum power.The aim of this work is to make a comparative of thephotovoltaic system performance using the three basictopologies of three different DC-DC converters. Thisare discussed below:1. Boost Converter: A power converter whose dcinput voltage is less than the dc output voltage.This means the PV input voltage is less than thebattery voltage in the system.Fig. 1 Single diode Equivalent circuit of solar cell2.CONVERTERSIMULATIONDesigning of ConvertersDESIGNANDFig.3 circuit diagram of Boost converter2. Buck-Boost Converter: This is a combination ofbuck converter and a boost converter. Here, theoutput voltage can be increased or decreased with@ IJTSRD Available Online @ www.ijtsrd.com Volume – 1 Issue – 6 Sep - Oct 2017Page: 1277

International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470respect to the input voltage by varying the dutycycle.Fig. 4 Circuit Diagram of Buck-Boost Converter3. Cuk converter:CuK converter is actually the cascade combinationof a boost and a buck converter. The capacitor C1acts as a primary means to store and transfer thepower from input to output. The voltage vc1 isalways greater than either input or output voltage.The average output to input relations are similar tothat of a buck-boost converter circuit.q is the electron charge [1.60217646・10 19C], k isthe Boltzmann constant[1.3806503・10 23J/K], T[K] is the temperature of the p-n junction, and a is thediode ideality constant.ParameterImpVmpValue7.6126.3 VParameterNsI0,nPmaxIscVoc200.1438.21 A32.9 VIpvaRpKvValue549.825·10 8 A8.214 A1.3415.405ohm0.221 ohm-0.1230RsV/KKi0.0032A/KTable-1- Parameters of the KC200GT solararrayat 25 C,1000W/m2.5.RESULT AND DISCUSSION4.1. Result: Simulation of IV and PV curve of solararray:Fig. 5 Circuit representation of CuK converter4. SIMULATION OF SPV SYSTEMSimulation of Solar Array: Following shows theequivalent circuit of the ideal photovoltaic cell. Thebasic equation from the theory of semiconductors thatmathematically describes theI-V characteristic of theideal photovoltaic cell is:Fig 6: characteristics of solar array at 1000 W/squaremwhere Ipv, cell is the current generated by the incidentlight(it is directly proportional to the Sun irradiation),Id is the Shockley diode equation, I0,cell [A] is thereverse saturation or leakage current of the diode [A],@ IJTSRD Available Online @ www.ijtsrd.com Volume – 1 Issue – 6 Sep - Oct 2017Page: 1278

International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470Fig. 7PV characteristics of solar array at 1000W/square m.the desirable. And from converters, the best results areobtained from Cuk Converter since the output voltageis much closer to the actual. The output voltage of cukconverter is around 48V with inverted polaritywhereas the required output is also 48V.In the end, the IC MPPT Algorithm used model withCuk Converter has better results than P&O MPPTAlgorithm used model. So we would suggest using ICAlgorithm for Maximum Power Point Tracking ofsolar photovoltaic system and cuk converter formaintain output voltage constant.5.Fig 8: Variation in current with change in irradiation.4.2Discussion:In this project, we have gone through the Solar CellEquations and its Simulation. Along with this, we alsoincorporated the study of various MPPT Algorithmsfor maximum power output from the solar cell moduleor panel.From the various algorithms, we have implementedthe Incremental Conductance Algorithm in MatlabSimulink. We have compared the output from theSolar Cell incorporating MPPT Algorithm with theoutput without MPPT incorporation.Through solar array, we are getting the MPP currentof around 7.61A while the MPP voltage is around26.3V. The maximum power output we are gettingfrom solar array alone is around 200W. To get thisconstant output voltage, we have implemented theMPPT Algorithms with different converters like dc-dcBoost, Buck-Boost and Cuk Converter.Employing Boost converter, the results of MPPcurrent and power are almost same in both thealgorithms. There is minor variation with the actualvalue of MPP current and maximum power fromactual value. However there are reduced ripples uponimplementation of P&O algorithm. Employing BuckBoost Converter, however the values of MPP currentand maximum power are good but the ripples in theoutput voltage is much increased which arecompletely undesirable.Finally with Cuk Converter, the results are good andthe ripples are much reduced. However, the value ofMPP current and maximum power are almost equaland the output voltage across the load almost equal toCONCLUSIONS1. There is higher number of applications of SPVsystem like space applications, providingelectricity to remote areas etc.2. Simulation of solar cell gives us a in depth idea ofsolar cell and the origin of its characteristics.3. MPPT increases the efficiency of SPV systemwith tracking efficiencies ranging from 80%-99%.4. Reaching a stable, true MPP at steady state insteadof oscillating around this point would furtherimprove the system’s efficiency and increasereliability.5. Thus, implementing the Incremental ConductanceAlgorithm is a good choice.6. Through simulation we can see that the systemcompletes the maximum power point trackingsuccessfully despite of fluctuations. When theexternal environment changes suddenly thesystem can track the maximum power pointquickly. Although there is little deviation in theresults, the overall trends and forms are practical.Future Work:In future, we would like to develop two differentworking model of Solar Photovoltaic systememploying these algorithms practically using CukConverter.REFERENCES1) Zhou Xuesong, Song Daichun, Ma Youjie, ChengDeshu, “The simulation and design for MPPT ofPV system Based on Incremental ConductanceMethod” WASE International Conference onInformation Engineering,2010.2) Jacob James Nedumgatt, Jayakrishnan K.B.Umashankar S.Vijayakumar , Kothari D P“Perturb and Observe MPPT Algorithm for SolarPV Systems-Modeling and Simulation,” IEEE@ IJTSRD Available Online @ www.ijtsrd.com Volume – 1 Issue – 6 Sep - Oct 2017Page: 1279