Optimization of Solar Energy Production using PLC and SCADA

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Optimization of Solar En Ener erg gy Pro Produ duct ctio ion n usi using ng PL 1

1

Abhishe Kumar Chambel , Er. Bharti Sood

2

2

Electrical and Electronics Engineering, Electronics & Communication E ngineering Maharaja Agra en University, Baddi, Himachal Pradesh, India

ABSTRACT This This pape paperr focu focuse sess on on the the maxi maximi mizz ing the solar energy produced by Solar cells through the development of such a Sun-Tracking s stem that can be implemented using PLC & SCADA.

The developed tracking system is innovative in relat relatio ion n to to the the usual usual sun track tracking ing syste syste s available in the the mark market et.. In In fact fact,, the the deve develo lope ped d solu solu tion has many advantages in relation to similar existi ng devices, as this system can automatically work in order to optimize the energy production of pho tovoltaic cells as we we kn know th that in in cas casee of of fi fixed xed S lar cells, the effi effici cien ency cy is very very poor poor.. Thi Thiss eff effic icie ie cy of power gene genera rati tion on by Sola Solarr cel cells ls can can be incr increa ea sed using this system, system, so so that that as the the position position of su changes, the position position of Solar Solar cell cell is automa automatica ticall ll y adjusted by using stepper motors. An experimental prototype was built built and field field resul results ts have have pro prov v n the good performance of the developed tracking s ystem. KEY

& SCADA

WORDS:

Solar Cells, Phot voltaic cells, Track Trackin ing g Syst System ems, s, Inte Intell llige igent nt sen sensor sorss a d Supervisory Control.

1. INTRODUCTION Acco Accord rdin ing g to mar marke kett econ economy omy,, t worldwide demand for energy, forces rise on the the price price of fossil fossil combus combustible tible expected expected in in the near near future future,, that th energ energy y will will grow grow fas faster ter than than the the find findii available fossil resources.

e increasing a continuous . In fact, it is demand for g out of new

This market market behaviou behaviourr brings brings a positiv e challenge to the scientific community as more fund are allocated for for the the rese resear arch ch and and deve develo lopm pmen entt of n w alternatives to the usual ma main en energetic so urces (fossil combu combusti stible bles). s). In In this this contex context, t, nowad nowadaa ys more effort is being being done done to conse conserve rve the fossi fossill fu fu ls and also to

find ind alt alteernati nativ ve eene nerg rgy y re resou sou rces to meet the power demands. In this paper a system for Optimization of Solar Energy generation using PLC & SCADA is developed. Nowadays, Solar power generation has very low efficiency efficiency in terms o f availability, utilization and generation (ca. 12%). Sola Solarr Ene Energ rgy y is is suc such h an an ene enerr y which is available to us in abundance abundance and withou t any limits. The Solar 17 Energy incident on Earth at osphere is 10 Watts. The The Solar Solar Energ Energy y that that rea reach ch s the earth’s surface is 16 10 Watts. The total power requirements of whole 13 world is 10 Watt. If, 5% of he total energy received at the surface is fully utilized, it is still 50 times more than the actual requirement of the whole world. This paper focuses on the opt imization of the electric energy production by sol ar cells through the deve develop lopmen mentt of of an an inte intelli llige ge t sun-tracking system. The developed tracking system is innovative in rela relati tion on to the the usu usual al sun sun tra track cking systems available in the marke market. t. The The usual usual availa availab b le solutions for tracking syst systeems rely on the the knowl nowlee ge of the geographical position of the solar panel on the earth surface. With this knowl knowledg edgee it is possi possibl ble to know the relative position position of the the sun, sun, on a tim basis, according to the well-known solar tables. Moder Modern n solut solution ionss inco incorpo rpora rate a GPS system to calculate the position of the olar panel on the Earth surface surface.. The orientati orientations ons t be followed by the photov tovolta oltaic ic panel, on a reg lar time-base, are then pre-pr pre-progra ogrammed mmed,, on an ope loop approach. There are are sig signi nifi fica cant nt effo effort rtss on on t e optimization of sun tracking systems as it is ocumented by several reg registe istere red d int inter erna nati tion onal al pate pate ts. These solutions are based either on the above des ribed principle either on

@ IJTSRD | Available Online @ www.ijtsrd.com | Volume – 3 | Issue – 1 | Nov-De 2018

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International Journal of Trend in

cientific Research and Development (IJTSRD) ISSN: 2456-6470

the quantification of the received solar energy, either on the the maxi maximi miza zati tion on of the the sola solarr inci inci dent radiation through the use of light concentration le ns. The solution developed in this paper is innovative related to the above referred approaches as this system is aut auton onom omou ouss reg regar ardi ding ng the the info inform rmat at ion needed to process the optimal orientation and it is intelligent in a way way that that it moni monito tors rs,, on on a real real-t -tii e base, the photovol photovoltaic taic energ energy y product production ion an d it avoids systematic failures coming from ch anges on the assumed values (position, initial infrastructure orientation, orientation, cleanness cleanness of the the photovoltai photovoltai c cells, etc.). 2. SYSTEM DESCRIPTION: A. Overall System Presentation The overall system is presented in fig. 1. The complete strategy is composed by 5 sub -systems: 1. Electro-Mechanical Structure 2. Control Unit 3. Supervisory System 4. Wind-meter 5. Photovoltaic Park.

photovoltaic park in order to ransfer the new optimal orie orient ntat atio ion n to all all PVPV-pr prod oduc ucti ti n panels. B. Electro-Mechanical Structure The operational subset of the tracking system, named Electro Electro-Mec -Mechan hanical ical System, System, i presented in figs 2 and 3. This This struc structur turee has has two DOF, motorized by stepper motors with incorporated enc oders; in order to track exactly the prescribed path. The mechanical system was designe designed d using using standar standar industrial Aluminium profiles in order to obtain simple and economic structure.

The mechanical structure is mainly composed by Bosch Profiles and Alumi ium plates. The two motorized axis are comp osed by Step-motors assembled to Aluminium sh fts. Figure 2 illustrates the the seve severa rall main main comp compon onee ts of the mechatronic system: Part Part n. 6 = Ste Stepp-Mo Moto torr to to con contt rol axis 1; Part Part n. 7 = Ste Stepp-Mo Moto torr to to con contt rol axis 2; Part n. 8 = Photovoltaic cell (1 50mmx150mm).

Fig 2 Ele Elecctro tromec mechanica ical Sy Sys tem for Solar Tracking Fig.1 overall system presenta tion The The devel develope oped d track tracking ing syste system m searc search h s the optimal orientat orientation ion of a surfac surface, e, related related to th sun incident radiation. The global performance of the system is described below. The planar surface is omposed by a photovol photovoltaic taic cell cell which which is motoriz motorized ed b 2-orthogonal axis. These two controlled DOF (Degrees of Freedom) are managed by a PLC ( rogrammable Logic Logic Controlle Controller) r) according according to to a searc program that compa mpares the the electric tric powe ower prod ced by the photovol photovoltaic taic cell in each each corr correspo esponde nde nt orientation. The The ma maxima ximall pow power er valu valuee is is sto stored and the correspondent or orientations on on bo both mo mot orized axis are stored. This new optimal orientation f the tracking system is then communicated to the industrial

Fig.3 De Design of Deg Degree of freedom Figure 3 details the two desi ned degrees of freedom (DOF).


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C. Control Unit The control unit consist of PLC Si mens S7-300 system (Programmable Logic Con troller). This control control system system has has the comple complett operational manag manageme ement nt of the the tracki tracking ng syste system. m. The main tasks performed by the system are:  Contro Controlli lling ng of the two stepp stepper er moto moto s;  Proc Proces essi sing ng the the dat dataa fro from m bot both h enc encod od ers;  Processing the vo voltage si signal co co ing from the Solar-Cell;  Proc Proces essi sing ng the the data data from from the the exte exte nal proximity sensor sors th that inf info orms the the sy system tem a out the hardhome position reference.

In the the develo developed ped supervis supervisor or y system, the SCADA application manages the ov rall system dynamics. The Communication flux b tween the supervisory system and the control unit is illustrated in fig. 5. The SCADA PC is is simul simultane taneousl ously a SCADA server and an internet server, as the implemented SCADA application is web enabled.

This This PLC PLC contr controls ols direct directly ly the track trackii g system and commands all other Solar-Panels, from the solar Park, through a Profibus-DP network. Figu Figure re 4 sho shows ws an exam exampl plee of of a so lar park with several PV-Panels. PV-Panels. Figure Figure 5 illustrate the Profibus network implemented in this study. Figure 5 This Figure from a first solar white paper. “’Grid-F “’Grid-Frien riendly’ dly’ UtilityUtility-sca scall PV Plants,” illustrates the basic architecture and co ponents of a Plant-level Control system 3. EXPERIMENTAL PROTOTYPE A. Physical Description The prototype built followed the design presented in figure 2. This system incorporates a PVcell150mmx150mm, Pmax=1,12W, (Polycrystalline Silicon Silicon wafe wafer) r) and and the whole structure is made of Aluminium alloy. In fig. 6 the global developed prototype is shown.

Fig 4 Solar Panel Power Pl nt D. Supervisory System A SCA SCADA DA syst system em (Sup (Super ervi viso sory ry Con Con trol and Data Acquisition) is implemented to monitor and supervise the the tr tracking ing sy system. tem. A Sup Supeervisor isory y Co Co ntrol and Data Acquisition (SCADA) System is used as an application de development to tool th that e ables system integrators to create sophisticated su pervisory and control applications for a variety of technological domai domains, ns, mainly mainly in the indust industry ry field. The main featu feature re of of a SCAD SCADA A syste system m is its ability to communicate with control equipment in the field, through the PLC network. As the equipment is moni monito tore red d and and data data is reco record rded ed,, a SCA SCA A application responds according to system logic re quirements or operator requests.

Fig.6 Prototype assembly The co control trol unit was was de developed using an industrial Siemens S7-300 PLC (Programmable Logic Contro Controlle ller) r).. The sele selecte cted d PLC system is a modular devi device ce tha thatt is con const stit itut uted ed by by t e following modules:


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Slot1 = Power supply PS 307-2A Slot2 = Processor CPU 315-2DP Slot4 = Communication module CP 342 -5 Slot5 = Digital card DI8/DO8xDC24V/ ,5A Slot6 = Analog card AI8 x12bit Slot7 = Analog card AO4 x12bit Slot8 = FM card – Counter Module (F 350) Slot9 = FM card – Counter Module (F 350) Slot10 = FM card – Stepper Motor (FM 353) Slo Slot11 t11 = FM ca card – Stepp teppeer Mo Motor tor (F (FM 353)

B. Implemented Control Algorithm The The softw software are used used for for the the PL programming was the Siemens Simatic Step 7, with the Simatic 7 ProdaveV5.5 needed for the ommunication between the Scada Scada sys system tem and and the the PL network. The designed control algorithm was imple ented using the Ladder Diagram language.

The The dev devel elop oped ed cont contro roll alg algor orit it m is illustrated in fig.8.

Addi Additi tion onal ally ly,, the the PLCPLC-tr trac acke kerr has has a mo mo dem for GSM communic communicatio ation n that that provide providess the the syst systee m capacity to communicate through the mobile phone network. The driving unit is composed by two otorized axis, with the following characteristics: 1. Axis 1  Step motor: Nanotec ST4018L0804, 50Ncm;  Opt. Encoder: HP HEDL-5540 A14, 500 Pulses  Coupling unit: Oldham D5  Proximity sensor: Omrom EA2 M8 NP 2. Axis 2  Step motor: Nanotec ST5918L1008, 170Ncm;  Gear box: Nanotec PLE40-1S-4  Opt. Encoder: HP HEDL-5540 A14, 500 Pulses  Coupling unit: Oldham D25  Proximity sensor: Omron EA2 M8 NP Figure Figure 7 detail detailss the the electr electro-me o-mecha chanic nic l structure of the developed sun-tracker system.

Fig.8 Fig.8 Control Control Algorit Algorithm hm fo the Tracking System A short description of the asks performed by the tracker tracker control controller, ler, regardin regarding the above referred algorithm, is described below:

Fig 7 Prototype Prototype Assembly: Assembly: Sola r panel

Box0: Box0: After After reset reset is activa activate te , the system stores the PV-power generated in the a ctual position, P actual, in the variable Pin. The system searches its referencenull position. It moves until it finds the hard-home position (b (both ex external pr proxi ity sensors on). In this position the system assumes the absolute orientation angle ngless for for both both axis axis equa equall z ro (α1 = α2 = 0). The maximal maximal Power, Power, Pmax Pmax is se to zero. Bothcounters, C1, C2, are loaded;


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Box1: Box1: After After start start is activate activated, d, the the syste syste m initiates the sear search ch for for the the max maxim imal al powe powerr gen gener eraa ted in axis 1, with an angle increment α10. The sys em stores the power generated in variable P1. Box2: If P1 < P max, the system goes to Box 4, and follows for a new position; Box3: If P1 > P max, this position is stored in the variables: α1max, α2max. The max Po er value, P max is actualized with the new Power value P1; Box4: Counter for axis 1 is updated; Box5: After all orientations for axis 1 are evaluated, regarding regarding a fixed orientation orientation for axi axi 2, axis 2 is posi positi tion oned ed in a new new pos posit itio ion, n, with with an a gle increment α20, 20, and and axis axis 1 retu return rnss to to its its ini initi tial al posi posi ion α1=0. The system re-initiates the search for the optimal orie orient ntat atio ion n of axis axis 1, 1, rega regard rdin ing g the the n w position of axis axis 2. The The info informa rmatio tion n flux flux retu return rnss to b ox 1. Box6: After all orientations for axis 1 are evaluated, regarding all different positions of axis 2, the system compares the maximal power found ( max) with the initia initiall Power Power gene generat rated ed,, befor beforee the sear sear h process had begun (Pin). If the new Power value is greater than a prepre-de defi fine ned d gain gain,, this this new new cor corre resp spon ond d nt orientation (α1max, α2max) is sent to all park panels. If the powe powerr gai gain n is is not not enou enough gh,, the the new new fo fo nd position is not to follow by the other PV-panels. Box7: After a pre-defined time interval (K) the tracker system initiates a new complete search rocess in both axis. axis. The informa information tion flux flux returns returns to to bo 0. C. SCADA Supervisory System The SCADA system used to i plement this monitoring and control control strategy permit s the selective access to the application, depending on the user’s responsibility degree. In this paper we developed three user levels: Operators, Su ervisors and Administrators.

Fig 9 SCADA view f Solar Tracker As this SCADA platform is eb enabled, all the GUI display displayed ed data data is also also on-lin on-lin accessible through the internet. In fig. 9 it is is sh shown the devel oped main menu for the sunsun-tr trac acke kerr syst system em.. The The on-l on-lii e available information, referri referring ng actual actual data data from from th tracker unit is: actual posit position ion for for both both axis axis,, actu actu l PV-power generated, max. daily PV-power gene ated, actual efficiency ratio. 4. CONCLUSIONS The develope developed d tracker tracker for su su radiation worked very well. The increase in power eneration, in relation to other Solar Energy-systems, ithout tracking devices, is of similar magnitude (ca. 5%) as for other usual trac tracki king ng solu soluti tion ons. s. Howe Howeve ver, r, t his system has a relative advantage, as it measures exactly the controlled variable: the actual Solar pow r generation.

can jus justt uti utili lize ze 5% of the total available Note: If we can solar energy energy on earth earth surface surface , it will be 50 times the ener energy gy whic which h is requ requir ired ed by by the whole world. And in this way, there will never be any shortage of power supply except in case of n n-availability of direct sunlight. In such such cas case, e, the other other sourc sourc s of power can be used so that that we use use as muc much h less less fossil fuels as possible.

Several Several SCADA menus menus were were buil built. The main characteristic of a SCADA Menu is to be simple, explicit and quick on transmitting the information to the operator or to the System administra tor.

REFERENCES JOURNAL / CONFERENCE PAPERS 1. Bajpai P, Kumar S, “D sign, development and performance test of an a utomatic two-axis solar trac tracke kerr syst system em”, ”, Ann Annu ual IEEE Conference Publication, India Confe ence (INDCON) 2011, Electr. Eng. Dept., IIT Kharagpur, Kharagpur, 1618 Dec. 2011, 1–6.

One of the developed Graphical User In terfaces (GUI) is shown in fig 9.

2. Esram T, Kimball JW, Midya P, ”Dynamic

rein PT, Chapman PL, aximum power point


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tracking of photovoltaic arrays using ripple correlation control”, IE IEEE Trans ctions. 2006; 21(5), Illinois Univ., Urbana, IL , Sept. 2006, 1282–1291. 3. Feng-ru Feng-run n Liu, Liu, Le Xiao, Xiao, Wen-ji Wen-jiaa Li Li ,” The design of automatic solar tracking system or solar cell”, IEEE IEEE 2nd Interna Internation tional al Conferen Conferencc on Artificial Intelligence, Management Science nd Electronic Commerce (AIMSEC) 2011; North China University of Technology, China, 8- 10 Aug. 2011, 4451–4454 4. Huif Huifen eng g Jiao Jiao,, Jian Jianzh zhon ong g Fu, Fu, Yuc Yuc un Li, Jintao Lai, Lai, “Design “Design of automatic automatic two-a two-axi xi s sun-tracking system”, IEEE International C nference on Mechanic Mechanic Automation Automation and Contro l Engineering (MACE) 2010, Dept. of Mech. ng., Zhejiang Univ., China, 26-28 June 2010, 232 –2326. 5. Khan MT MTA, Ta Tanzil SM SMS, Ra Rah an R, Alam SMS.” Design Design and construction construction o an automatic solar tracking system”, IEEE 6th International Confere Conference nce on on Electri Electrical cal an Computer Engineering (ICECE), 2010, Dept. of Electr. &

Elec Electr tron on.. Eng Eng., ., [7] [7] Sim Simaa ic Net – NCM S7 for Profib Profibus/ us/ FMS. FMS. SIE SIEME MEN N 12/2001. 6. System Software for Reference Manual, A5E00069892-02

7-300 and S7-400 – SIEMENS 08/2000;

7. Simatic S7 Prodave S7 PCs, SIEMENS, 2001

Toolbox for PGs and

8. Simatic Simatic S7-30 S7-300 0 – Ladde Ladde Logic (LAD) for S7300, SIEMENS, 2001. 9. WinCC-Advanced/Pro for SCADA Systems 10. Weiping Luo ,” A solar p nels automatic tracking system based on Omron PLC”, Asian Control Conference(ASCC)2009, Wuhan University of Science & Engineering Engineering, China, 27-29 Aug. 2009,1611-1614. 11. Zhang Bao-jian, Gao Guo-hong, Zhu Yanli.” li.”D Desig signmen ment of autom tom tic tracking system of sola solarr ene energ rgy y sys syste tem m , 2nd International Conf Confer eren ence ce on on Indu Indust stri rial Mechatronics and Automation, 20 2010, Co Com ut. Sci. Dept., Henan Inst. of Sci. & Techn l., China, 30-31 May 2010689–691.


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Optimization of Solar Energy Production using PLC and SCADA

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