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With the rapid evolving IT technologies, today, the power factor correction (PFC) design is facing many challenges, such as power scalability, high entire-load-range efficiency, and high power density. Power scalability is a very desirable and cost-effective approach in the PFC design in order to keep up with servers' growing power requirements. Higher power density can eventually reduce the converter cost and allows for accommodating more equipment in the existing infrastructures. Driven strongly by economic and environmental concerns, high entire-load-range efficiency is more and more required by various organizations and programs, such as the U.S. Energy Star, Climate Savers, and German Blue Angel. Today, the existing boost PFC is reaching its limitations to meet these challenges simultaneously. Using the cutting-edge semiconductor devices, further efficiency improvement at light load is still needed. There are limited approaches available for increasing the power density due to the large EMI filter and inductor size. Interleaved multi-channel boost PFC is a promising candidate to meet those challenges, but the interleaved boost converter is a less explored area. On the other hand, the multi-channel interleaved buck converter for the VR application has been intensively studied and thoroughly explored. One basic approach of this study is trying to extend the existing knowledge and techniques obtained from multiphase buck converters to the multi-channel interleaved boost converters since there are similarities existed between the multi-phase buck and the multi-channel boost converters. The existing studies about the interleaving impact on the EMI filter design are based on the time domain ripple cancellation effect. This approach is good enough for most of the filter designs. However, unlike the conventional filter designs, the EMI filter design is a specification related process. Both the EMI standard and the EMI measurement are based on the frequency domain spectrum. Limited by the existing analysis approaches, it is difficult to provide a clear picture about how exactly the multi-channel interleaving will impact the EMI filter design. The interleaving impact on the Common Mode (CM) noise also has not been studied in any existing literatures for the same reason. In this study, the frequency domain analysis method was adopted. With the double Fourier integral transformation, a closed-form expression of all the harmonics of the noise sources can be obtained. With all the detailed phase relationship of the switching frequency harmonics and all the side band harmonics, the multi-channel interleaving impact on both the differential mode (DM) and CM filter design can be clearly understood and summarized. According to the design curves provided, the EMI filter size can be effectively reduced by properly choosing the interleaving channel number and the switching frequency. The multi-channel interleaving impact on the output capacitor current ripple is also studied and summarized in this dissertation. It should be pointed out that interleaving only reduces the total input and output current ripples; the inductor current in each channel still has large ripple if small inductance is used. Similar to the multi-phase buck converter, coupling inductors result in different equivalent inductances for input current ripple and inductor current ripple for boost converters. Keeping the inductor current ripple magnitude the same, inverse coupling inductors between the interleaved channels can reduce the inductor size. However, the DM filter size is increased due to larger input current. Based on the investigation on the total magnetic component weight, inverse coupling inductor can reduce the total magnetic component weight. The reduction is more pronounced for lower switching frequency design when the inductor size is dominating among the total magnetic components. Based on the harmonic cancellation, and with all the detailed phase relationship of the switching frequency harmonics and all the side band harmonics, a novel phase angle control method is proposed to maximize the reduction of the EMI filter. For example, in a 2-channel interleaved PFC, just by changing the interleaving scheme to 90 degree phase shift, 39% total volume reduction of the EMI filter can be achieved. The proposed phase angle controlled multi-channel PFC is experimentally demonstrated and verified on a digital controlled 4-channel PFC. The phase angle control method proposed in the multi-channel boost converter can be applied back to the multi-phase buck converter as well. The harmonic cancellation principle will be the same as the multi-channel boost converter. The same benefits can be obtained when the requirement is defined in the frequency domain, e.g. the EMI Standard. The interleaved multi-channel configuration makes it possible to implement the phase-shedding to improve the PFC light load efficiency. By decreasing the number of active channels according to the load, the PFC light load efficiency can be optimized. However, shedding phases can reduce the ripple cancellation effect as well, which will result in the EMI noise increase and losing the benefit on the EMI filter. By applying the proposed phase-shedding with phase angle control strategy, the phase shedding impact on the EMI filter design can be minimized. The light load efficiency can be improved without compromising the EMI filter size. Then, adaptive frequency controlled PFC is proposed to further improve the PFC light load efficiency. The proposed light load efficiency improvement strategies are combined and implemented on the platform of the digital controlled 4-channel PFC. The benefit of improving the light load efficiency is experimentally verified. The EMI performance is also evaluated with the EMI measurement results obtained from the PFC prototype. Following the same approach explored, the benefits of interleaved boost converter can be further extended other applications, such as the boost converter in the Hybrid Electric Vehicles (HEV) and photovoltaic (PV) system. / Ph. D.

The More-electric aircraft (MEA) concept has been raised since 1990s in order to increase fuel economy and reduce environmental impact of aircrafts. The fundamental of the concept is to replace pneumatic, hydraulic and mechanical systems in conventional aircrafts with its electrical equivalent that is lighter and more reliable. In this movement, power electronics technology plays a key role in interfacing the new types of electrical loads to the new aircraft electrical power system. One of the major tasks for power electronics circuits in MEA is to transfer aircraft variable frequency AC voltage into DC voltage, which could be conveniently utilized by different types of loads or power buses. The converters carrying out the task is commonly known as "rectifiers". This work aims at designing and constructing rectifiers that can work efficiently and reliably in more-electric aircrafts. One of the major challenge for these rectifiers comes from the complex aircraft environment. The ambient temperature could be as high as 70 ºC. Moreover, active cooling for converters may not be desirable. To deal with this, rectifiers should achieve extreme efficiency (especially at full load) so that all the components are not overheated without active cooling. This work aims at achieving extreme converter efficiency through advanced converter topologies and design. Both single-phase and three-phase rectifiers are discussed in this work. For single-phase rectifiers, this work focused on boost-type power factor correction (PFC) converters due to the promising efficiency and good PFC characteristics. The well-known two-level semi-bridgeless PFC boost rectifier, together with its interleaved and three-level counterparts, are studied and compared in this work. The operation principles of the converters are analyzed. Models and methods for converter efficiency evaluation are discussed. The efficiency evaluation of the topologies shows the advantage of three-level topologies and interleaved topologies in achieving higher efficiency and better thermal management. For three-phase rectifiers, two-level boost rectifier, three-level neutral point clamped (NPC) rectifier and Vienna rectifier are investigated. The evaluation shows the advantage of Vienna rectifier in achieving high efficiency due to reduced switching loss. Based on the evaluation of single-phase and three-phase active rectifiers, the author selected interleaved Vienna rectifier to achieve extreme efficiency and avoid overheating problem. The operation principle of the interleaved Vienna rectifier is introduced, with particular attention paid to the circulating current generated by interleaving operation. The design procedure for achieving maximum efficiency is described. Finally, a prototype of the proposed converter is constructed, which achieves 99.26% efficiency at nominal load. / Master of Science

The critical conduction mode (CRM) power factor correction converters (PFC) are widely used in industry for low power offline switching mode power supplies. For the CRM PFC, the main advantage is to reduce turn-on loss of the main switch. However, the large inductor current ripple in CRM PFC creates huge DM EMI noise, which requires a big EMI filter. The switching frequency of the CRM PFC is variable in half line cycle which makes the EMI characteristics of the CRM PFC are not clear and have not been carefully investigated. The worst case of the EMI noise, which is the baseline to design the EMI filter, is difficult to be identified. In this paper, an approximate mathematical EMI noise model based on the investigation of the principle of the quasi-peak detection is proposed to predict the DM EMI noise of the CRM PFC. The developed prediction method is verified by measurement results and the predicted DM EMI noise is good to evaluate the EMI performance. Based on the noise prediction, the worst case analysis of the DM EMI noise in the CRM PFC is applied and the worst case can be found at some line and load condition, which will be a great help to the EMI filter design and meanwhile leave an opportunity for the optimization of the whole converter design. What is more, the worst case analysis can be extended to 2-channel interleaved CRM PFC and some interesting characteristics can be observed. For example, the great EMI performance improvement through ripple current cancellation in traditional constant frequency PFC by using interleaving techniques will not directly apply to the CRM PFC due to its variable switching frequency. More research needs to be done to abstract some design criteria for the boost inductor and EMI filter in the interleaved CRM PFC. / Master of Science

The boost power factor correction (PFC) circuit is a common circuit in power electronics. Through years of experience, many designers have optimized the design of these circuits for particular applications. In this study, a new design procedure is presented that guarantees optimal results for any application. The algorithm used incorporates the principles of evolution in order to find the best design. This new design technique requires a rethinking of the traditional design process. Electrical models have been developed specifically for use with the optimization tool. One of the main focuses of this work is the implementation and verification of computationally efficient thermal and electro-magnetic interference (EMI) models for the boost PFC circuit. The EMI model presented can accurately predict noise levels into the 100's of kilohertz range. The thermal models presented provide very fast predictions and they have been adjusted to account for different thermal flows within the layout. This tuning procedure results in thermal predictions within 10% of actual measurement data. In order to further reduce the amount of analysis that the optimization tool must perform, some of the converter design has been performed using traditional methods. This part of the design is discussed in detail. Additionally, a per unit analysis of EMI and thermal levels is introduced. This new analysis method allows EMI and thermal levels to be compared on the same scale thus highlighting the tradeoffs between the both behaviors. / Master of Science

This thesis focuses on the study, implementation and improvement of a digital controller for a power factor correction (PFC) converter. The development of the telecommunications industry and the Internet demands reliable, cost-effective and intelligent power. Nowadays, the telecommunication power systems have output current of up to several kilo amperes, consisting of tens of modules. The high-end server system, which holds over 100 CPUs, consumes tens of kilowatts of power. For mission-critical applications, communication between modules and system controllers is critical for reliability. Information about temperature, current, and the total harmonic distortion (THD) of each module will enable the availability of functions such as dynamic temperature control, fault diagnosis and removal, and adaptive control, and will enhance functions such as current sharing and fault protection. The dominance of analog control at the modular level limits system-module communications. Digital control is well recognized for its communication ability. Digital control will provide the solution to system-module communication for the DC power supply. The PFC converter is an important stage for the distributed power system (DPS). Its controller is among the most complex with its three-loop structure and multiplier/divider. This thesis studies the design method, implementation and cost effectiveness of digital control for both a PFC converter and for an advanced PFC converter. Also discussed is the influence of digital delay on PFC performance. A cost-effective solution that achieves good performance is provided. The effectiveness of the solution is verified by simulation. The three level PFC with range switch is well recognized for its high efficiency. The range switch changes the circuit topology according to the input voltage level. Research literature has discussed the optimal control for both range-switch-off and range-switch-on topologies. Realizing optimal analog control requires a complex structure. Until now optimal control for the three-level PFC with analog control has not been achieved. Another disadvantage of the three-level PFC is the output capacitor voltage imbalance. This thesis proposes an active balancing solution to solve this problem. / Master of Science

En aéronautique, les contraintes sont telles que la masse des filtres peut représenterjusqu'à 50% de la masse totale du convertisseur. Ces dernières années, les convertisseursmulticellulaires parallèles entrelacés et magnétiquement couplés ont conduit à améliorer lesperformances des convertisseurs (densité de puissance, efficacité, dynamique,...). Denombreuses topologies de filtrages entrelacés existent, l'objectif principal de cette étude est detrouver parmi ces topologies celles qui sont les mieux adaptées à la réalisation d’un onduleurde tension 110Veff / 400Hz triphasé 25kVA. Il est démontré que le choix du type de matériaumagnétique a un impact déterminant sur le poids, le volume et les pertes du convertisseur. Quidit parallélisation, dit multiplication du nombre de semi-conducteurs. Ces nouvelles structuresdoivent garantir à la fois un rendement élevé, une masse faible et une continuté defonctionnement, même en cas de panne d’un semiconducteur de puissance ou de sacommande. Mais coupler les phases entre elles, impose un lien indissociable qui peut êtrenuisible au fonctionnement de la structure en cas de dysfonctionnement. Des solutionsexistent et sont abordées dans l’étude. Enfin, la réalisation pratique d'un prototype semiindustrielde convertisseur triphasé utilisant des transformateurs interphases est présentée. Ils’agit d’un onduleur réseau avionique triphasé avec reconstruction de neutre pour fonctionneren déséquilibré. Les résultats expérimentaux démontrent l’avantage d’un convertisseur / In aeronautics field, the constraints are such as the mass of the filters can represent upto 50% of the total mass of the converter. During the last years, magnetic coupled interleavedconverters enhances performances (power density, efficiency, transient response). It existeseveral possibilities for use interleaved coupled topologies that use inter-phase transformerexist, the main objective of this study is to find among these topologies the best adaptedconfiguration in the context of a three-phase voltage inverter 110Veff/400Hz 25kVA. Thechoice of the magnetic material type has a great impact on determining the weight, thevolume and the losses of the converter. Parallelization leads to increase the semiconductornumber. These new structures must guarantee at the same time a raised efficiency, a low massand a great reliability, even in the event of case of breakdown of a power semiconductor orhis driver circuit. But coupleing the phases between themselve, imposes a dangerous stronglink on the structure operation in event of default. Solutions exist and are presented in thestudy. Lastly, the implementation of a semi-industrial of three-phase converter using interphasestransformers is performed. This inverter has been desinging to be use on a three-phaseavionics inverter network with rebuilding of neutral in case of unbalancing. Experimentalresults show the advantage of an interleaved converter compared with a conventional solution.

Die intratracheale Applikation von Perfluorcarbonen (PFC) in ungeschädigte Lungen, z.B. als Röntgenkontrastmittel und zur PFC-induzierten cerebralen Kühlung, wird derzeit diskutiert. Ob es aufgrund der Dichte und Sauerstofflöslichkeit der PFC zu einer Beeinflussung der cerebralen Oxygenierung und Hämodynamik durch die pulmonale PFC Applikation kommt, ist bisher unbekannt. Änderungen der Konzentration von cerebralem oxygeniertem und totalem Hb koennen mittels Near-infrared Spectroscopy gemessen werden. I.) Effekt durch die PFC-Applikation in gesunde Lungen neugeborener Ferkel: Es wurden zwei verschiedene Applikationsgeschwindigkeiten (30 ml PFC pro kg Körpergewicht als Bolusgabe versus 1,5 ml/min pro kg) und zwei Füllvolumen (30 versus 10 ml/kg) verglichen. Die Bolusgabe bewirkt einen sofortigen Abfall des PaO2 und der cerebralen Oxygenierung, bei langsamer Gabe des gleichen Volumens ist dies weniger ausgeprägt. Mit 10 ml/kg PFC fand sich nahezu keine Beeinflussung der Parameter. II.) Effekte der Änderung der FiO2 in PFC-gefüllten Lungen: Hierfür wurden Änderungen der FiO2 unter konventioneller Druckbeatmung vor PFC-Applikation und unter PFC-Füllung (30 oder 10 ml/kg PFC) verglichen. Beide PFC-Volumen (mit FiO2 1,0) bedingten PaO2-Werte wie unter CMV mit FiO2 von 0,5. Mit 30 ml/kg PFC kam es unter FiO2 von 0,5 zur Abnahme des cerebralen oxygenierten Hb. Zusammenfassend ergibt sich, dass die Applikation von 10 ml PFC/kg bevorzugt werden sollte. Bei kompletter Füllung der Lungen werden durch langsame Applikation cerebrale Nebenwirkungen minimiert. In PFC-gefüllten gesunden Lungen ist zum Erhalt der systemischen und cerebralen Oxygenierung die FiO2 zu erhöhen. / Intratracheal administration of perfluorochemicals (PFC) has been suggested for reasons other than respiratory insufficiency, such as pulmonary imaging and PFC-associated brain cooling. Due to their high density and oxygen solubility, PFC application has been described to affect systemic hemodynamics and oxygenation during liquid ventilation. Whether the PFC application into healthy lungs or changes in inspired oxygen fraction (FiO2) in PFC-filled healthy lungs affects cerebral hemodynamics is not known. Changes in the concentration of cerebral oxygenated and total Hb can be measured by near-infrared spectroscopy (NIRS). I.) Initial effects of PFC application into healthy lungs of newborn piglets: Two different filling modes (rapid versus slow) and two different filling volumes (slow filling of 30 versus 10 ml PFC/kg body weight) were compared. Rapid filling caused an immediate drop of systemic and cerebrale oxygenation, which was less prominent by filling 30 ml/kg PFC slowly. Almost no changes for all parameters were found with 10 ml kg/PFC. II.) Effects of variations in FiO2 in the PFC filled lungs of healthy piglets: Changes in FiO2 during conventional mechanical ventilation (CMV) prior to PFC-application and in the PFC-filled lungs (30 ml/kg or 10 ml/kg PFC) were compared. Both PFC-volumes (at a FiO2 of 1.0) caused PaO2-values that were similar to CMV with FiO2 of 0.5. In the 30 ml/kg PFC group a reduction of cerebral oxygenated Hb was found at FiO2 of 0.5. According to the data application of 10 ml/kg PFC should be preferred. If complete filling of the lung is needed, the slow administration of PFC minimizes cerebral side effects. In PFC- filled healthy lungs an increase in FiO2 is necessary to maintain systemic and cerebral oxygenation.

Eine phasische Ausschüttung des Neurotransmitters Dopamin wird u.a. mit positivem Affekt, der Reaktivität auf Neuheit und kognitiver Handlungssteuerung in Verbindung gebracht. In der vorliegenden Doktorarbeit wurde der dopaminerge Einfluss auf die Flexibilität und Stabilität der Handlungssteuerung untersucht. Für eine zielgerichtete Handlung sind beide antagonistischen Anforderungen notwendig. Einerseits müssen gewählte Handlungsabsichten gegenüber irrelevanten Ablenkungsreizen abgeschirmt und somit stabilisiert werden. Andererseits müssen diese Absichten im Falle handlungsrelevanter Änderungen der Situation flexibel angepasst werden. Als theoretische Grundlage für die vorliegende Arbeit dienten in diesem Zusammenhang folgende Kernthesen von Miller und Cohen (2001): (1) Der präfrontale Kortex (PFC) ist entscheidend an der Regulation der Handlungssteuerung beteiligt. (2) Eine phasische Dopaminausschüttung ermöglicht die Aufnahme neuer Reize im PFC und damit die Möglichkeit, gegebenenfalls aktuelle Regeln und Ziele zu ändern. (3) Eine phasische Dopaminausschüttung verschiebt demnach die Balance zwischen einer flexiblen und stabilen Handlungssteuerung in Richtung Flexibilität. In den ersten beiden Studien der vorliegenden Arbeit wurde der Einfluss interindividueller Unterschiede dopaminerger Aktivität auf die Flexibilität der Handlungssteuerung untersucht. Als Prädiktoren wurden die spontane Lidschlagrate (EBR), die Polymorphismen COMT Val-158-Met und DRD4 Exon III sowie das Geschlecht eingesetzt. In der dritten Studie sollte eine Dopaminausschüttung experimentell durch die Darbietung von Signalen einer potenziellen Belohnung (Geldgewinn) stimuliert werden. Hierdurch sollten die beobachteten Zusammenhänge aus den ersten beiden Studien erhärtet und in einem erweiterten theoretischen Kontext untersucht werden. In allen drei Studien zeigte sich ein signifikanter Zusammenhang von Lidschlagrate und kognitiver Flexibilität (mittleres η²=8%). Entsprechend der Vorhersage wurde mit steigender Lidschlagrate eine erhöhte Flexibilität beobachtet. Ferner ergaben sich Interaktionseffekte zwischen EBR und DRD 4 Exon III Polymorphismus bzw. EBR und Geschlecht, sowie ein Geschlechtshaupteffekt. Zur Stabilität dieser Effekte konnte jedoch jeweils keine abschließende Aussage gemacht werden. In der dritten Studie zeigte sich bei Darbietung des Belohnungssignals eine erhöhte kognitive Stabilität (η²=7%). Dieser Zusammenhang wurde vom subjektiven Erlebens des Experiments moderiert (η²=11%): Personen, die den Eindruck hatten, ohne große Anstrengung viel zu gewinnen, zeigten eine erhöhte kognitive Flexibilität. Diese beiden Befunde können innerhalb einer integrativen Theorie von Cohen et al. (2004) plausibel erklärt werden. Der Belohnungs-Haupteffekt könnte auf die Dominanz eines (noradrenergen) Wirkungspfades im Kontext der Wettkampfsituation hinweisen. Der moderierende Effekt des subjektiven Erlebens könnte gemäß der oben erläuterten Kernthesen von Miller und Cohen (2001) als gleichzeitige Flexibilisierung über den dopaminergen Wirkungspfad interpretiert werden, die insbesondere bei geringer wahrgenommener Anstrengung dominieren kann. Als wichtigstes Ergebnis der vorliegenden Arbeit kann zusammenfassend festgestellt werden, dass die Hypothese einer dopaminergen Beeinflussung der Flexibilitäts-Stabilitäts-Balance der kognitiven Handlungssteuerung durch die Ergebnisse der drei Studien unterstützt werden konnte. Dabei erwies sich insbesondere die spontane Lidschlagrate als zuverlässiger non-invasiver und effizient zu erhebender Prädiktor dopaminerger Aktivität. Der flexibilisierende Einfluss von Dopamin kann von einem stabilisierenden Einfluss überlagert werden. Dies ist insbesondere dann der Fall, wenn eine erforderliche Leistung zur Erreichung einer Belohnung als nützlich eingeschätzt und subjektiv als anstrengend wahrgenommen wird. / Converging evidence suggests a modulatory role of the neurotransmitter dopamine concerning reward, positive affect, novelty, and cognitive control. According to Miller and Cohen (2001) a phasic burst of dopamine shifts the balance between cognitive flexibility versus stability towards increased flexibility. Based on this assumption the current dissertation aimed at revealing associations between correlates of dopaminergic activity and the cognitive flexibility in an attentional set-shifting paradigm. In the first two studies we examined individual differences in the spontaneous eyeblink rate (EBR), the polymorphisms DRD4 exon III and COMT Val158Met polymorphism, as well as gender. In the third study we examined the impact of prospective monetary gains. Through this the findings of the first two studies should be validated and tested in an extended theoretical background. In all three studies an association between high EBR and increased cognitive flexibility was observed (mean η²=8%). Thus the main thesis of Miller and Cohen (2001) could be confirmed. Furthermore we observed interactions between EBR and DRD4 and EBR and gender, as well as a gender main effect on cognitive flexibility. In the third study we observed increased cognitive stability in the face of prospective gains (η²=7%). However, this effect was modulated by the subjective evaluation of the reward cues: participants who reported increasing their effort in response to reward cues showed increased cognitive stability whereas those who reported a positive and relaxed attitude towards the reward cues showed increased flexibility (η²=11%). The results thus suggest that the flexibility-stability-balance is modulated by the perceived effort needed to receive the potential reward.

[pt] As alterações no solo decorrentes de um elemento de fundação profunda e seus desempenhos sob a aplicação de carga axial são processos há muito tempo estudados na engenharia civil. Diversos fatores como, método de instalação utilizado, formato da estaca, interações solo-estrutura, mecanismos de transferências de carga, movimentação do solo e alterações na compressibilidade e tensões do solo adjacente, apresentam desafios importantes que ainda não foram totalmente compreendidos nos fenômenos de penetração e capacidade de suporte em estacas. Diversos avanços foram realizados ao longo das últimas décadas para se investigar estes comportamentos, a partir procedimentos experimentais e novas formas de instrumentação, assim como ferramentas numéricas sofisticadas com o emprego de complexos modelos constitutivos em elementos finitos. Apesar destes avanços, a modelagem numérica dos processos citados, com todas as suas complexidades, ainda encontra alguns desafios. Devido a facilidade em lidar com simulações de grandes deformações e de captar o comportamento dilatante e nãolinear de solos granulares, o Método dos Elementos Discretos apresenta uma excelente ferramenta para investigar estes processos, sem grandes complicações. O presente trabalho procurou avaliar os comportamentos obtidos a partir de diferentes processos de instalação da estaca e seus efeitos nos resultados da prova de carga estática em solos granulares. As alterações de tensão e deslocamento foram avaliadas nos diferentes modelos e discutindo sobre uma metodologia básica para obter correspondências qualitativas e quantitativas com os diferentes comportamentos de campo e laboratório. Para este estudo foram utilizados os programas PFC, na versão 2D, e o programa UDEC, da Itasca co. / [en] The disturbances experienced by the soil owing to the load applied to a deep foundation and its relative behavior consist of long time studied phenomena in civil engineering. Several factors such as the installation methods, the pile geometry, the interactions between soil and structure, the load-transfer mechanisms, the soil movements and the disturbances in the stress and compressibility fields present major challenges that have not yet been completely understood. Numerous advances have been observed throw-out the last decades, in order to investigate these behaviors starting from the different pile instrumentations, the use of calibration cameras and centrifuges and most recently the measurement of the stress and strain fields inside the soil mass in model tanks. Despite the advances the numerical modelling of those processes still faces major challenges. Due to simplified approach used by the Discrete Element Method to simulate large deformation and the dilant non-linear behavior of granular soils, it presents as an excellent tool to investigate these processes without further complications. The present work proposed to evaluate the different behaviors obtained with the variations of installation methods investigated as well as their effects in the results of the Pile Load Test. The disturbances were also evaluated in the different models considered and a basic method to achieve qualitative and quantitative comparisons was discussed. These studies were made possible with the help of the PFC2D and UDEC programs developed by Itasca co.