Improved electrochemical performance of Sr₂Fe_1.5Mo_0.4Nb_0.1O_6-�� -Sm_0.2Ce_0.8O_2-�� composite cathodes by a one-pot method for intermediate temperature solid oxide fuel cells

<p>In this paper, Sr₂Fe_1.5Mo_0.4Nb_0.1O_6-�� (SFMNb)-xSm_0.2Ce_0.8O_2-�� (SDC) (x = 0, 20, 30, 40, 50 wt%) composite cathode materials were synthesized by a one-pot combustion method to improve the electrochemical performance of SFMNb cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs). The fabrication of composite cathodes by adding SDC to SFMNb is conducive to providing extended electrochemical reaction zones for oxygen reduction reactions (ORR). X-ray diffraction (XRD) demonstrates that SFMNb is chemically compatible with SDC electrolytes at temperature up to 1100 ��C. Scanning electron microscope (SEM) indicates that the SFMNb-SDC composite cathodes have a porous network nanostructure as well as the single phase SFMNb. The conductivity and thermal expansion coefficient of the composite cathodes decrease with the increased content of SDC, while the electrochemical impedance spectra (EIS) exhibits that SFMNb-40SDC composite cathode has optimal electrochemical performance with low polarization resistance (R_p) on the La_0.9Sr_0.1Ga_0.8Mg_0.2O₃ electrolyte. The R_p of the SFMNb-40SDC composite cathode is about 0.047 �� cm² at 800 ��C in air. A single cell with SFMNb-40SDC cathode also displays favorable discharge performance, whose maximum power density is 1.22 W cm^-2 at 800 ��C. All results indicate that SFMNb-40SDC composite material is a promising cathode candidate for IT-SOFCs.</p>

An Efficient Precoder Design for Multiuser MIMO Cognitive Radio Networks with Interference Constraints

We consider a linear precoder design for an underlay cognitive radio multiple-input multiple-output broadcast channel, where the secondary system consisting of a secondary base-station (BS) and a group of secondary users (SUs) is allowed to share the same spectrum with the primary system. All the transceivers are equipped with multiple antennas, each of which has its own maximum power constraint. Assuming zero-forcing method to eliminate the multiuser interference, we study the sum rate maximization problem for the secondary system subject to both per-antenna power constraints at the secondary BS and the interference power constraints at the primary users. The problem of interest differs from the ones studied previously that often assumed a sum power constraint and/or single antenna employed at either both the primary and secondary receivers or the primary receivers. To develop an efficient numerical algorithm, we first invoke the rank relaxation method to transform the considered problem into a convex-concave problem based on a downlink-uplink result. We then propose a barrier interior-point method to solve the resulting saddle point problem. In particular, in each iteration of the proposed method we find the Newton step by solving a system of discrete-time Sylvester equations, which help reduce the complexity significantly, compared to the conventional method. Simulation results are provided to demonstrate fast convergence and effectiveness of the proposed algorithm.��

Collaudo funzionale di un inverter trifase per trazione elettrica stradale

Lo scopo della tesi �� collaudare un inverter trifase per trazione elettrica stradale al fine di determinarne le specifiche nominali e di massima. Il lavoro �� stato organizzato procedendo inizialmente con l���individuazione delle parti principali che concorrono alla formazione del convertitore, studiandone il principio di funzionamento e i diversi valori di tensione e di corrente che ne caratterizzano le prestazioni. Successivamente si �� passati al collaudo della parte di potenza del convertitore con l���obiettivo di determinarne le prestazioni in relazione alla massima temperatura consentita di funzionamento. Questo tipo di prova ha richiesto l���individuazione di una sorgente di alimentazione dell���inverter in grado di fornire i picchi di potenza necessari durante la fase di sovraccarico (si tratta di diversi kW per alcune decine di secondi) e contemporaneamente di un carico trifase in grado di assorbire queste potenze senza danneggiarsi. E��� molto importante tenere presente che la prova per la determinazione delle prestazioni nominali dell���inverter, richiede una durata di diverse decine di minuti cio�� fin tanto che l���inverter non ha raggiunto l���equilibrio termico e quindi la temperatura non varia apprezzabilmente nel tempo. Allo scopo si �� impiegata come sorgente di alimentazione un pacco di batterie Litio-Ioni costituito da 32 celle da 160Ah collegate in serie per una tensione nominale di 105V, mentre come carico si �� utilizzato un motore asincrono trifase collegato direttamente in uscita dell���inverter.

Analisi sperimentale del funzionamento di un sistema micro-ORC

Questa tesi tratta nello specifico lo studio di un impianto micro-ORC, capace di sfruttare acqua alla temperatura di circa 70-90��C come sorgente termica. Questo sistema presenta una potenza dichiarata dal costruttore pari a 3kW e un rendimento del 9%. In primo luogo, si descrivono le caratteristiche principali dei fluidi organici, in particolare quelle del freon R134a, impiegato nel banco prova. Vengono illustrati dettagliatamente l���impianto e la sensoristica utilizzata per le misurazioni delle varie grandezze fisiche. Tramite esse, con l���utilizzo di un programma di acquisizione dati appositamente relizzato in ambiente LabVIEW, �� stato possibile calcolare in tempo reale tutti i parametri di funzionamento, necessari per la caratterizzazione del sistema. Per una veloce ed efficiente elaborazione dei dati registrati durante le prove in laboratorio, �� stato realizzato un programma in linguaggio VBA. L���utilizzo di questo codice ha permesso, in primo luogo, di individuare e correggere eventuali errori di calcolo e acquisizione presenti in ambiente LabVIEW e, in secondo luogo, si �� reso indispensabile per comprendere il funzionamento dell���impianto nelle varie fasi, come accensione, spegnimento e produzione di potenza. Sono state inoltre identificate le modalit�� di risposta del sistema al variare dei comandi impostabili dall���utente, quali il numero di giri della pompa e la variazione della temperatura della sorgente calda. Si sono poi osservate le risposte del sistema al variare delle condizioni esterne, come ad esempio la temperatura dell���acqua di condensazione. Una specifica prova �� stata analizzata in questo elaborato. Durante tale prova il sistema ha lavorato in forte off-design, erogando una potenza elettrica pari a 255 W, raggiungendo un basso valore del rendimento (pari a 1.8%). L���analisi dei dati ha portato ad identificare nuovi limiti di funzionamento, legati ad esempio alla quantit�� di fluido interna al sistema.

Algoritmi per il calcolo parametrico delle curve a "V" e delle curve di "Capability" delle macchine sincrone

Nell'elaborato, dopo una breve descrizione di come vengono suddivise le macchine elettriche a seconda che vi siano o meno parti in movimento al loro interno, vengono esaminati inizialmente gli aspetti teorici che riguardano le macchine sincrone a poli lisci ed a poli salienti prendendo in esame anche quelli che sono i provvedimenti necessari a ridurre il contributo dei campi armonici di ordine superiore. Per questo tipo di macchine, spesso utilizzate in centrale per la pruduzione dell'energia elettrica, risultano di fondamentale importanza le curve a "V" e le curve di "Capability". Esse sono strumenti che permettono di valutare le prestazioni di tali macchine una volta che siano noti i dati di targa delle stesse. Lo scopo della tesi �� pertanto quello di sviluppare un software in ambiente Matlab che permetta il calcolo automatico e parametrico di tali curve al fine di poter ottimizzare la scelta di una macchina a seconda delle esigenze. Nel corso dell'eleaborato vengono altres�� proposti dei confronti su come varino tali curve, e pertanto i limiti di funzionamento ad esse associati, al variare di alcuni parametri fondamentali come il fattore di potenza, la reattanza sincrona o, nel caso di macchine a poli salienti, il rapporto di riluttanza. Le curve di cui sopra sono state costruite a partire da considerazioni fatte sul diagramma di Behn-Eschemburg per le macchine isotrope o sul diagramma di Arnold e Blondel per le macchine anisotrope.

Dise��o optimizado de alimentaci��n de servicios auxiliares de un parque e��lico off-shore en aguas profundas

<p>[ES]La energ&iacute;a e&oacute;lica marina supone respecto a la energ&iacute;a e&oacute;lica en tierra una mayor generaci&oacute;n de energ&iacute;a, debido a condiciones menos turbulentas del viento y m&aacute;s constantes que permiten mayores di&aacute;metros de palas y por tanto mayor generaci&oacute;n de energ&iacute;a. En este trabajo se estudia la eficiencia energ&eacute;tica en los sistemas auxiliares de una plataforma offshore con aerogenerador para obtenci&oacute;n de energ&iacute;a e&oacute;lica, y se aplican medidas de ahorro y racionalizaci&oacute;n energ&eacute;tica. El ahorro de energ&iacute;a har&aacute; m&aacute;s viable la instalaci&oacute;n de un sistema de posicionamiento din&aacute;mico en las plataformas, en el trabajo se estudia esta posibilidad, de manera que se asegure un mejor recurso, y la posibilidad de instalaci&oacute;n sin restricciones legislativas y de profundidades excesivas.</p>

Renewable energy scenarios for South Karelia ��� non-industrial energy demands

T��ss�� diplomity��ss�� tarkastellaan t��ysin uusiutuvaa energiaj��rjestelm���� Etel��-Karjalan maakunnan alueella, mik�� onkin jo t��ll�� hetkell�� Suomen uusiutuvin maakunta. Diplomity��ss�� tarkastellaan julkisen sektorin, liikenteen ja rakennusten energian kulutusta mutta teollisuuden energiank��ytt�� j��tet����n tarkastelun ulkopuolelle. Ty��ss�� tutustutaan t��m��n hetken Etel��-Karjalan energiaj��rjestelm����n ja sen perusteella tehd����n referenssi-skenaario. Tulevaisuuden skenaariot tehd����n vuosille 2030 ja 2050. Tulevaisuuden skenaarioissa muutos keskittyy j��rjestelm��n s��hk��istymiseen ja uusiutuvien tuotantomuotojen integroimiseen j��rjestelm����n. S��hk��istyminen kasvattaa s��hk��nkulutusta, joka pyrit����n kattamaan uusiutuvilla tuotantomuodoilla, l��hinn�� tuuli- ja aurinkovoimalla. Liikennesektori rajataan kumipy��r��liikenteeseen ja sen muutos tulee olemaan haastavin ja aikaa vievin. Muutokseen pyrit����n liikennepolttoaineiden tuotannolla maakunnassa sek�� s��hk��autoilulla. Uusiutuva energiaj��rjestelm�� tarvitsee tuotannon ja kysynn��n joustoa sek�� ��ly�� j��rjestelm��lt��. Ty��ss�� tarkastellaan my��s j��rjestelm��n kustannuksia sek�� ty��llisyysvaikutuksia.

Riffe und fazielle Entwicklung der florigemma-Bank (Korallenoolith, Oxfordium) im S��ntel und ��stlichen Wesergebirge (NW-Deutschland

During the Sedimentation of the platform carbonate deposits of the Korallenoolith Formation (middle Oxfordian to early Kimmeridgian) small buildups ofcorals formed in the Lower Saxony Basin. These bioconstructions are restricted to particular horizons (Untere Korallenbank,��origenuna-Bank Member etc.) and represent patch reefs and biostromes. In this study, the development of facies, fossil assemblages, spatial distribution of fossils, and reefs of the ��origenuna-Bank Member (upper Middle Oxfordian) in the S��ntel Mts and the eastern Wesergebirge Mts is described; the formation of reefs is discussed in detail. Twelve facies types are described and interpreted. They vary between high-energy deposits as well winnowed oolites and quiet-water lagoonal mudstones. Owing to the significance of biota, micro- and macrofossils are systematically described. The reefs are preserved in growth position, are characterized by numerous corresponding features and belong to a certain reef type. According to their size, shape and framework, they represent patch reefs, coral knobs (sensu James, 1983), coral thrombolite reefs (sensu Leinfelder et al., 1994) or ���Klein- and Mitteldickichte��� (sensu Laternser, 2001). Their growth fabric corresponds to the superstratal (dense) pillarstone (sensu Insalaco, 1998). As the top of the ��origenuna-Bank displays an erosional unconformity (so-called Hauptdiskontinuit��t), the top of the reefs are erosionally capped. Their maximum height amounts to at least the maximum thickness of the ��origenuna-Bank which does not exceed 4 metres. The diversity of coral fauna of the reefs is relatively low; a total of 13 species is recorded. The coral community is over- whelmingly dominated by the thin-branched ramose Thamnasteria dendroidea (Lamouroux) that forms aggregations of colonies (77?. dendroidea thickets). Leafy to platy Fungiastrea arachnoides (Parkinson) and Thamnasteria concinna (Goldfuss) occur subordinately, other species are only of minor importance. In a few cases, the reef-core consisting of Th. dendroidea thickets is laterally encrusted by platy F. arachnoides and Th. concinna colonies, and microbial carbonates. This zonation reflects probably a succession of different reef builders as a result of changing environmental conditions (allogenic succession). Moreover, some reefs are overlain by a biostrome made of large Solenopora jurassica nodules passing laterally in a nerinean bed. Mikrobial carbonates promoted reef growth and favoured the preservation of reef organismn in their growth position or in situ. They exhibit a platy, dendroid, or reticulate growth form or occur as downward-facing hemispheroids. According to their microstructure, they consist of a peloidal, clotted, or unstructured fabric (predominately layered and poorly structured thrombolite as well as clotted leiolite) (sensu Schmid, 1996). Abundant endo- and epibiontic organisms (bivalves, gastropods, echinoids, asteroids, ophiuroids, crabs etc) are linked to the reefs. With regard to their guild structure, the reefs represent occurrences at which only a few coral species serve as builder. Moreover, microbial carbonates contribute to both building and binding of the reefs. Additional binder as well as baffler are present, but not abundant. According to the species diversity, the dweller guild comprises by far the highest number of invertebrate taxa. The destroyer guild chiefly encompasses bivalves. The composition of the reef community was influenced by the habitat structure of the Th. dendroidea thickets. Owing to the increase in encrusting organisms and other inhabitants of the thickets, the locational factors changed, since light intensity and hydrodynamic energy level and combined parameters as oxygen supply declined in the crowded habitat. Therefore a characteristic succession of organisms is developed that depends on and responds to changing environmental conditions (���community replacement sequence���). The succession allows the differentiation of different stages. It started after the cessation of the polyps with boring organisms and photoautotrophic micro-encrusters (calcareous algae, Lithocodium aggregatum). Following the death of these pioneer organisms, encrusting and adherent organisms (serpulids, ���Terebella��� species, bryozoans, foraminifers, thecideidinids, sklerospongid and pharetronid sponges, terebratulids), small mobile organisms (limpets), and microbial induced carbonates developed. The final stage in the community replacement sequence gave rise to small cryptic habitats and organisms that belong to these caves (cryptobionts, coelobites). The habitat conditions especially favoured small non-rigid demosponges (���soft sponges���) that tolerate reduced water circulation. Reef rubble is negligible, so that the reefs are bordered by fossiliferous micritic limestone passing laterally in micritic limestone. Approximately 10% of the study area (outcropping florigemma-Bank) corresponds to reefal deposits whereas the remaining 90% encompass lagoonal inter-reefal deposits. The reef development is a good example for the interaction between reef growth, facies development and sea-level changes. It was initiated by a sea-level rise (transgression) and corresponding decrease in the hydrodynamic energy level. Colonization and reef growth took place on a coarse-grained Substrate composed of oncoids, larger foraminifers and bioclasts. Reef growth took place in a calm marine lagoonal setting. Increasing abundance of spherical coral morphs towards the Northeast (section Kessiehausen, northwestem S��ntel Mts) reflects higher turbidity and a facies transition to coral occurrences of the ��origenuna-Bank Member in the adjacent Deister Mts. The reef growth was neither influenced by stonns nor by input of siliciclastic deposits, and took place in short time - probably in only a thousand years under most probably mesotrophic conditions. The mass appearance of solenoporids and nerineids in the upper part of the ��origenuna-Bank Member point to enhanced nutrient level as a result of regression. In addition, this scenario of fluctuations in nutrient availability seems to be responsible for the cessation of reef corals. The sea level fall reached its climax in the subaerial exposure and palaeokarst development of the florigemma-Bank. The reef building corals are typical pioneer species. The blade-like, flattened F. amchnoides colonies are characterized by their light porous calcium carbonate skeleton, which is a distinct advantage in soft bottom environment. Thus, they settled on soft bottom exposing the large parts of its surface to the incoming light. On the other hand, in response to their light requirements they were also able to settle shaded canopy structures or reef caves. Th. dendroidea is an opportunistic coral species in very shallow, well illuminated marine environment. Their thin and densely spaced branches led to a very high surface/volume ratio of the colonies that were capable to exploit incoming light due to their small thamasterioid calices characterized by ���highly integrated polyps���. In addition, sideward coalescence of branches during colony growth led to a wave-resistant framework and favoured the authochthonous preservation of the reefs. Asexual reproduction by fragmented colonies promoted reef development as Th. dendroidea thickets laterally extend over the sea floor or new reefs have developed from broken fragments of parent colonies. Similar build ups with Th. dendroidea as a dominant or frequent reef building coral species are known from the Paris Basin and elsewhere from the Lower Saxony Basin (Kleiner Deister Mts). These buildups developed in well-illuminated shallow water and encompass coral reefs or coral thrombolite reefs. Intra- and inter-reef deposits vary between well-winnowed reef debris limestone and mudstones representing considerably calmer conditions. Solenoporid, nerineids and diceratides belong to the characteristic fossils of these occurrences. However, diceratides are missing in theflorigemma-Bank Member. Th. dendroidea differs in its colonization of low- to high-energy environment from recent ramose scleractinian corals (e.g., Acropora and Porites sp.). The latter are restricted to agitated water habitats creating coral thickets and carpets. According to the morphologic plasticity of Th. dendroidea, thick-branched colonies developed in a milieu of high water energy, whereas fragile, wide- and thin-branched colonies prevail in low-energy settings. Due to its relatively rapid growth, Th. dendroidea was able to keep pace with increased Sedimentation rates. 68 benthonic foraminiferan species/taxa have been recognized in thin sections. Agglutinated foraminifers (textulariids) predominate when compared with rotaliids and milioliids. Numerous species are restricted to a certain facies type or occur in higher population densities, in particular Everticyclammina sp., a larger agglutinated foraminifer that occurs in rock building amounts. Among the 25 reef dwelling foraminiferal species, a few were so far only known from Late Jurassic sponge reefs. Another striking feature is the frequency of adherent foraminiferal species. Fauna and flora, in particular dasycladaleans and agglutinated foraminifers, document palaeobiogeographic relationships to the Tethys and point to (sub)tropical conditions. Moreover, in Germany this foraminiferan assemblage is yet uncompared. In Southern Germany similar tethyan type assemblages are not present in strata as young as Middle Tithonian.

Implementation and Validation of a Self-Consumption Maximization Energy Management Strategy in a Vanadium Redox Flow BIPV Demonstrator

This paper presents the results of the implementation of a self-consumption maximization strategy tested in a real-scale Vanadium Redox Flow Battery (VRFB) (5 kW, 60 kWh) and Building Integrated Photovoltaics (BIPV) demonstrator (6.74 kWp). The tested energy management strategy aims to maximize the consumption of energy generated by a BIPV system through the usage of a battery. Whenever possible, the residual load is either stored in the battery to be used later or is supplied by the energy stored previously. The strategy was tested over seven days in a real-scale VRF battery to assess the validity of this battery to implement BIPV-focused energy management strategies. The results show that it was possible to obtain a self-consumption ratio of 100.0%, and that 75.6% of the energy consumed was provided by PV power. The VRFB was able to perform the strategy, although it was noticed that the available power (either to charge or discharge) varied with the state of charge.

Studio e sviluppo di un simulatore ed ottimizzatore di traiettoria per aerei da competizione

L'obbiettivo principale di questa tesi �� la creazione di un particolare strumento capace di calcolare, dati in input le coordinate geografiche in latitudine e longitudine dei vari gates di passaggio del velivolo e delle caratteristiche principali di quest'ultimo, la traiettoria ottimale, ovvero la pi�� veloce, restando pur sempre nei limiti strutturali e in quelli stabiliti dal regolamento, oltre che ad una serie di valori utili per effettuare tale percorso, quali la variazione di potenza, di coefficiente di portanza, di velocit��, ecc. Dopo una prima fase di raccolta delle informazioni (regolamento della competizione, dati tecnici dei velivoli usati, del motore e dell'elica) ne �� seguita una seconda in cui, partendo dall'analisi dei risultati ottenuti da un precedente tool di calcolo in Excel, si �� provveduto a scriverne uno nuovo operante in ambiente MatLab.

Analisi del rendimento di sistemi micro ORC di tipo sperimentale

In questo lavoro si analizza il rendimento isoentropico di diversi espansori adottati all���interno di sistemi micro-ORC (Organic Rankine Cycle). Si parte da una descrizione generale dei sistemi ORC, mettendone in evidenza le principali caratteristiche, il layout tipico, le differenze rispetto ad un ciclo Rankine tradizionale, e gli ambiti di utilizzo. Si procede ad una trattazione teorica del rendimento isoentropico del compressore e dell���espansore, specificando le ipotesi adottate nei calcoli e mettendo in luce la relazione tra rendimento isoentropico e politropico nell���uno e nell���altro apparato. Si passa poi alla descrizione delle quattro principali tipologie di espansori presenti in letteratura: scroll, screw, vane e piston, e si prosegue con l'analisi nel dettaglio della letteratura relativa alla valutazione dell���efficienza di questi quando utilizzati all���interno di un sistema micro-ORC. Infine, dopo aver descritto il sistema ORC del laboratorio di via Terracini del DIN, illustrandone layout, componenti principali, potenza scambiata all���interno dei componenti e modalit�� di calcolo adottata per la valutazione del rendimento isoentropico dell���espansore e del sistema complessivo, si confrontano i dati di efficienza di questo con quelli reperiti in letteratura. Il confronto del rendimento, dell'espansore e complessivo, del sistema del DIN, 33.8% e 1,818% rispettivamente, con quelli degli altri sistemi, �� risultato di difficilmente valutazione a causa delle condizioni di forte off-design del sistema stesso. Dalla ricerca �� inoltre emerso che i fluidi pi�� utilizzati nella sperimentazione, e dunque capaci di migliori prestazioni, sono R245fa, R134a e R123. Per quel che riguarda infine gli espansori, nel range di potenza di 1-10 kW, lo scroll risulta essere il migliore.

Hybrid Power System Intelligent Operation and Protection Involving Distributed Architectures and Pulsed Loads

Efficient and reliable techniques for power delivery and utilization are needed to account for the increased penetration of renewable energy sources in electric power systems. Such methods are also required for current and future demands of plug-in electric vehicles and high-power electronic loads. Distributed control and optimal power network architectures will lead to viable solutions to the energy management issue with high level of reliability and security. This dissertation is aimed at developing and verifying new techniques for distributed control by deploying DC microgrids, involving distributed renewable generation and energy storage, through the operating AC power system. To achieve the findings of this dissertation, an energy system architecture was developed involving AC and DC networks, both with distributed generations and demands. The various components of the DC microgrid were designed and built including DC-DC converters, voltage source inverters (VSI) and AC-DC rectifiers featuring novel designs developed by the candidate. New control techniques were developed and implemented to maximize the operating range of the power conditioning units used for integrating renewable energy into the DC bus. The control and operation of the DC microgrids in the hybrid AC/DC system involve intelligent energy management. Real-time energy management algorithms were developed and experimentally verified. These algorithms are based on intelligent decision-making elements along with an optimization process. This was aimed at enhancing the overall performance of the power system and mitigating the effect of heavy non-linear loads with variable intensity and duration. The developed algorithms were also used for managing the charging/discharging process of plug-in electric vehicle emulators. The protection of the proposed hybrid AC/DC power system was studied. Fault analysis and protection scheme and coordination, in addition to ideas on how to retrofit currently available protection concepts and devices for AC systems in a DC network, were presented. A study was also conducted on the effect of changing the distribution architecture and distributing the storage assets on the various zones of the network on the system���s dynamic security and stability. A practical shipboard power system was studied as an example of a hybrid AC/DC power system involving pulsed loads. Generally, the proposed hybrid AC/DC power system, besides most of the ideas, controls and algorithms presented in this dissertation, were experimentally verified at the Smart Grid Testbed, Energy Systems Research Laboratory. All the developments in this dissertation were experimentally verified at the Smart Grid Testbed.

Surfing the high energy output branch of nonlinear energy harvesters

Hysteresis and multistability are fundamental phenomena of driven nonlinear oscillators, which, however, restrict many applications such as mechanical energy harvesting. We introduce an electrical control mechanism to switch from the low to the high energy output branch of a nonlinear energy harvester by exploiting the strong interplay between its electrical and mechanical degrees of freedom. This method improves the energy conversion efficiency over a wide bandwidth in a frequency-amplitude-varying environment using only a small energy budget. The underlying effect is independent of the device scale and the transduction method and is explained using a modified Duffing oscillator model.

Different Parameters Variation Analysis of a PV Cell

The paper states an introduction, description and implementation of a PV cell under the variation of parameters. Analysis and observation of a different parameters variation of a PV cell are discussed here. To obtain the model for the purpose of analyzing an equivalent circuit with the consisting parameters a photo current source, a series resistor, a shunt resistor and a diode is used. The fundamental equation of PV cell is used to study the model and to analyze and best fit observation data. The model can be used in measuring and understanding the behaviour of photovoltaic cells for certain changes in PV cell parameters. A numerical method is used to analyze the parameters sensitivity of the model to achieve the expected result and to understand the deviation of changes in different parameters situation at various conditions respectively. The ideal parameters are used to study the models behaviour. It is also compared the behaviour of current-voltage and power-voltage by comparing with produced maximum power point though it is a challenge to optimize the output with real time simulation. The whole working process is also discussed and an experimental work is also done to get the closure and insight about the produced model and to decide upon the validity of the discussed model.