Genetic algorithm has been widely used in different areas of optimization problems. Ithas been combined with renewable energy domain, photovoltaic system, in this thesis.To participate and win the solar boat race, a control program is needed and C++ hasbeen chosen for programming. To implement the program, the mathematic model hasbeen built. Besides, the approaches to calculate the boundaries related to conditionhave been explained. Afterward, the processing of the prediction and real time controlfunction are offered. The program has been simulated and the results proved thatgenetic algorithm is helpful to get the good results but it does not improve the resultstoo much since the particularity of the solar driven boat project such as the limitationof energy production

Η παρούσα διπλωματική εργασία πραγματεύεται την ανάλυση και κατασκευή ενός αυτόνομου φωτοβολταϊκού συστήματος, το οποίο περιλαμβάνει αντλία. Ταυτόχρονα διενεργείται μελέτη ώστε το σύστημα να λειτουργεί στο σημείο μέγιστης αποδιδόμενης ισχύος. Η εργασία αυτή εκπονήθηκε στο Εργαστήριο Ηλεκτρομηχανικής Μετατροπής Ενέργειας του Τμήματος Ηλεκτρολόγων Μηχανικών και Τεχνολογίας Υπολογιστών της Πολυτεχνικής Σχολής του Πανεπιστημίου Πατρών. Σκοπός είναι η οδήγηση αντλίας χαμηλής ισχύος από φωτοβολταϊκό σύστημα, αξιοποιώντας όσο το δυνατόν πιο αποτελεσματικά την διαθέσιμη ηλιακή ακτινοβολία. Για να συμβεί αυτό παρεμβάλλεται μεταξύ των δύο στοιχείων μετατροπέας συνεχούς τάσης. Παράλληλα υλοποιείται κύκλωμα ελέγχου, ικανό να οδηγήσει το σύστημα στο μέγιστο σημείο ισχύος μέσω μεταβολής του λόγου κατάτμησης του μετατροπέα. Αρχικά αναλύεται το φωτοβολταϊκό φαινόμενο. Σαν αποτέλεσμα αυτής της ανάλυσης προκύπτει το ηλεκτρικό ισοδύναμο ενός φωτοβολταϊκού πίνακα, ο οποίος αποτελεί την πηγή ισχύος του συστήματος. Αναπτύσσεται το αντίστοιχο μοντέλο σε προγραμματιστικό περιβάλλον, το οποίο προσαρμόζεται ώστε τα χαρακτηριστικά του να αναπαριστούν πραγματικό πίνακα. Στη συνέχεια διερευνάται ο τρόπος που αλληλεπιδρά η πηγή ισχύος όταν συνδέεται σε φορτίο. Σύμφωνα με τα αποτελέσματα επιλέγεται το είδος του μετατροπέα που θα χρησιμοποιηθεί. Ακολουθεί η διαστασιολόγηση του μετατροπέα και η μοντελοποίηση του. Το επόμενο βήμα αποτελείται από την ανάλυση του κυκλώματος ελέγχου του συστήματος καθώς και τη μοντελοποίηση μηχανής συνεχούς ρεύματος συνδεδεμένη ως αντλία. Κατόπιν συνδέονται όλα τα μοντέλα και εξετάζεται η συνολική συμπεριφορά του συστήματος σε περιβάλλον SIMULINK. Τέλος κατασκευάζονται ο μετατροπέας και το κύκλωμα ελέγχου και αξιολογείται η συμπεριφορά τους βάσει πειράματος σε εργαστηριακές συνθήκες. / --

The assignment is issued by Scania Maintence AB seeking a new approach to detect power changes in their industrial processes. The work has taken place at Ångströmslaboratoriet and tests have been performed at Scania AB Södertälje. Today’s society consumes enormous amount of energy. In both economically and environmental view, it is important that the processes are effective, with high power factor. There are many ways to measure power in the industry, what they all have in common is that the installation is advanced, requires time and planning. Only a competent electrician may install the measuring device in the distribution box. The purpose of the project is to build a prototype for power measurement that can be easily used outside the distribution box, thus simplifying the procedure and shortening the time required. By attaching sensors around the supply cable, the magnetic field asymmetric flux density can be used and induce voltage proportional to the current in the cable. The result is an instrument that with a computer calculates current, phase angle and power. Measurements of the current rms value showed that the maximum difference between our prototype and Scania Maintenances equipmentis up to 29 percent. However, for a longer time (> 15 minutes) the differences between the mean values are only 1.2 percent and the accuracy is calculated to +/-3.67A with 95% confidence intervals. Phase angle accuracy measured to plus 6 minus and 15 percent. / Uppgiften är utfärdat av Scania Maintenance AB som söker en ny metod för att se effektförändringar i deras industriprocesser. Arbetet har ägt rum i Ångströmlaboratoriet (Uppsala universitet) och tester har utförts hos Scania AB Södertälje. Dagens samhälle förbrukar enorma mängder energi. Med hänsyn till både miljöpåverkan och ekonomi är det viktigt att processer är effektiva med höga verkningsgrader. Det finns många sätt att mäta effekt inom industrin, det de har gemensamt är att installationen är avancerad, kräver tid och planering. Endast en behörig elektriker får installera mätanordningen. Projektets syfte är att ta fram en prototyp för effektmätning som enkelt kan anmodas utanför centralen och därmed förenkla ingreppet och förkorta tidsåtgången. Genom att fästa sensorer runt ingående matningskabel kan magnetfältets asymmetriska flödestäthet utnyttjas och inducera spänning proportionell mot den ström som går i ledarna. Resultatet är ett instrument som tillsammans med en dator beräknar ström, fasvinkel och effekt. Vid mätning av strömmens effektivvärde beräknades den maximala skillnaden mellan vår prototyp och Scania Maintenances nuvarande utrustning upp till 29 %. Dock under en längre tid (> 15 min) är skillnaderna av medelvärdet endast 1.2 % och noggrannheten beräknas till 3.67A med 95 % konfidensintervall. Fasvinkelns noggrannhet beräknades till plus 6 och minus 12 %.

Οι φωτοβολταϊκές γεννήτριες παρουσιάζουν μια μη γραμμική χαρακτηριστική V-I και ένα σημείο λειτουργίας μέγιστης ισχύος (MPP) τα οποία ποικίλλουν ανάλογα με την ακτινοβολία και τη θερμοκρασία. Αυτή η εργασία παρουσιάζει έναν MPP-tracker βασισμένο στην ασαφή λογική και ένα σχέδιο ενός μονοφασικού inverter συνδεδεμένου στο ηλεκτρικό δίκτυο. Ο ασαφής ελεγκτής (FLC) παρέχει προσαρμοστικότητα στη επίδοση του συστήματος. Λαμβάνει υπόψη του το τρέχον φορτίο, τη θερμοκρασία, την ακτινοβολία, τον άνεμο καθώς και τις πιθανές σκιάσεις που καλύπτουν τα πλαίσια. Παρέχει επίσης άριστα χαρακτηριστικά όπως γρήγορη απόκριση, καλή επίδοση και την δυνατότητα να αλλάζουν οι παράμετροί του προκειμένου να βελτιώνεται ο έλεγχος του συστήματος. Το γεγονός ότι λαμβάνει υπόψη του τις εξωτερικές συνθήκες εξασφαλίζει καλύτερη γνώση της πραγματικής επίδοσης του φωτοβολταϊκού συστήματος και όχι της βέλτιστης επίδοσης που αυτό έχει στις πρότυπες συνθήκες (STC). Τα αποτελέσματα της προσομοίωσης επιβεβαίωσαν την αποτελεσματικότητα του προτεινόμενου συστήματος. / The photovoltaic generators show a non-linear characteristic VI and one maximum power point (MPP) which vary depending on insolation and temperature. This project presents a MPP tracker, based on fuzzy logic, and a plan of an one-phased grid connected inverter. Fuzzy logic controller provides adaptivity at the system’s performance. It takes into consideration current load, temperature, insolation, wind and possible shades covering the panels. It also provides excellent characteristics such as quick response, great performance and the capacity of changing the system parameters in order to improve the system control. The fact that it takes into consideration the external conditions (in vivo as opposed to in vitro-laboratorial conditions) ensures better knowledge of the actual performance of the photovoltaic systems and not the optimum performance the system can score in standard test conditions (STC). The results of this simulation have confirmed the effectiveness of the proposed system.

Submitted by Diogo Barreiros (diogo.barreiros@ufba.br) on 2017-03-10T14:39:59Z No. of bitstreams: 1 tese_alexandre_versao_final_bd.pdf: 3780030 bytes, checksum: 765f095f9626a12f3b43a6bf9fdb97f3 (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2017-03-10T14:52:25Z (GMT) No. of bitstreams: 1 tese_alexandre_versao_final_bd.pdf: 3780030 bytes, checksum: 765f095f9626a12f3b43a6bf9fdb97f3 (MD5) / Made available in DSpace on 2017-03-10T14:52:25Z (GMT). No. of bitstreams: 1 tese_alexandre_versao_final_bd.pdf: 3780030 bytes, checksum: 765f095f9626a12f3b43a6bf9fdb97f3 (MD5) / The automatic person re-identification (re-id) problem resides in matching an unknown person image to a database of previously labeled images of people. Among several issues to cope with this research field, person re-id has to deal with person appearance and environment variations. As such, discriminative features to represent a person identity must be robust regardless those variations. Comparison among two image features is commonly accomplished by distance metrics. Although features and distance metrics can be handcrafted or trainable, the latter type has demonstrated more potential to breakthroughs in achieving state-of-the-art performance over public data sets. A recent paradigm that allows to work with trainable features is deep learning, which aims at learning features directly from raw image data. Although deep learning has recently achieved significant improvements in person re-identification, found on some few recent works, there is still room for learning strategies, which can be exploited to increase the current state-of-the-art performance. In this work a novel deep learning strategy is proposed, called here as coarse-to-fine learning (CFL), as well as a novel type of feature, called convolutional covariance features (CCF), for person re-identification. CFL is based on the human learning process. The core of CFL is a framework conceived to perform a cascade network training, learning person image features from generic-to-specific concepts about a person. Each network is comprised of a convolutional neural network (CNN) and a deep belief network denoising autoenconder (DBN-DAE). The CNN is responsible to learn local features, while the DBN-DAE learns global features, robust to illumination changing, certain image deformations, horizontal mirroring and image blurring. After extracting the convolutional features via CFL, those ones are then wrapped in covariance matrices, composing the CCF. CCF and flat features were combined to improve the performance of person re-identification in comparison with component features. The performance of the proposed framework was assessed comparatively against 18 state-of-the-art methods by using public data sets (VIPeR, i-LIDS, CUHK01 and CUHK03), cumulative matching characteristic curves and top ranking references. After a thorough analysis, our proposed framework demonstrated a superior performance.

This thesis work aimed to develop solar Photovoltaic (PV) powered smart street post. The post was set to serve on highways for wild animals’ detection and warn vehicles of possible crossings. The main aim was to design reliable standalone PV system via PVSyst software and experimenting four different PV technologies including a bifacial module under. Another aim was to select and develop the hardware and software terms of the smart street pot. Radar sensor and analog to digital (A/D) data acquisition (DAQ) card were set to be used for the motion detection. RF wireless communication module was used for communicating with nearby posts to send data and trigger warning light emitting diodes (LED) sign. A Raspberry Pi microcontroller was programmed to control the operation of the street post through processing the signal from radar sensor and communicating with nearby posts. The PV system design included generation of street post’s daily profile, sizing and selection of the components of the system including the module, battery, charge controller and power stage circuit. The later was designed to provide suitable voltage level and interface for the loads connected. PVSyst model was built and set to be located in Ulm, Germany. The design parameters were set, and different set of orientations were tested for each module. The simulation results showed bifacial module delivered a reliable PV system in case of south and south-east orientation and achieved better performance in other orientations in comparison to the other PV modules implemented. Due to limitations in PVSyst software the results provided had an overall uncertainty of 5%. The microcontroller was able to process the data from the radar sensor and DAQ card and perform fast Fourier transform (FFT). However, further processing of motion detection was complex to be included in the thesis work. The radar sensor and DAQ card provided signals with uncertainty of ± 3.4 mV. The RF wireless communication module transmitted signal over various ranges up to 150 m with time delay of 500 ms.

Many companies want a lot of functionality over the web. Is it possible to achieve the same functionality on the web compared to an ordinary windows application? Our work aims towards evaluating which one of the solutions that is the best. Many customers wants a standalone application rich of functionality and demands to have the same functionality on the web. Is it always possible to achieve the costumer’s requirements on a web based solution or do you have to settle with an implementation of a standalone application? There are some factors that the answer depends on: performance, security, usability and implementation. The application that will be tested is developed in .Net and is a maintenance application for Business Intelligence (BI). We will have a short introduction to the Business Intelligence field to make you understand the purpose of the application.

Distributed energy is an attractive alternative to typical centralized energy sources specifically for remote locations not accessible to the electricity grid. With the continued advancement into new renewable technologies like solar, wind, fuel cell etc., off-grid standalone systems are becoming more attractive and even compeating on a cost basis for rural locations. Along with the environmental and sustainable movement, these technologies are only going to get more and more popular as time goes on. Power electronic converters are also advancing which will help the shift in electricity options. Creating innovative power electronic systems will be important when moving toward smaller, more e cient and higher power density solutions. As such, this thesis will aim to design and create an integrated power electronic system for an o -grid standalone solar application designed for remote rural locations with no access to electricity, or in locations which could bene t from such a system. It is designed for a DC input source from 24V-40V, such as a solar panel, and can operate four di erent loads; one 12V-24V 100 W DC load, charge a 48V battery, run three 5V cell phone charger outputs and run one 230V, 50Hz, 1 kW AC load. A boost converter, buck converter, phase shifted full bridge isolated DC-DC converter and a single phase inverter are implimented in the integrated system to achieve these outputs. A comparison of similar products on the market are presented and compared with the proposed design by showing the product speci cations, advantages and disadvantages of each. A discussion of each converter in the system is presented and will include operation, design and component selection. An in-depth design process for the inductor within the boost converter is presented and will cover core, winding design and an optimization algorithm using the Genetic Algorithm (GA) is used to compare di erent ferrite based C-C shaped inductors. More speci cally, the core material selected is Ferroxcube 3C97 and the inductor comparions are between di erent Litz bundled windings from New England Wire Tecnologies and a customized rectangular winding. The GA optimizes around the lowest volume by comparing the di erent inductor designs using the di erent Litz winding constructions and the custom rectangular winding constrictuion. The rectangular winding achieves the lowest volume and will be compared with a three phase interleaved boost design implimenting a CoilCraft inductor. The buck converter is the simplest converter and is designed using the traditional methods in literature. An in-depth design process for the phase shifted full bridge converter is also done wherein the zero voltage switching (ZVS) is achieved. The DC-AC inverter is the last converter designed within the integrated system and covers input capacitor sizing, and output lter design. There are speci c distributed energy standards that must be followed when connecting loads to the system and so the purpose of the lter is to lter out the voltage harmonics. The control techniques for each converter is also discussed and shown to operate in both simulation and in experimentally. The losses within the system are discussed and the required equations are de ned / Thesis / Master of Applied Science (MASc)

The tendency to use renewable energy resources has grown continuouslyover the past few decades, be it due to fear over warnings of globalwarming or because of the depletion and short life of fossil fuels or evenas a result of the interest which has developed among researchers doingscientific research into it. This work can be considered as joining any ofthese groups with an objective of giving electric light to the poorpopulation living in one of the poorest nations in the world.The aim of the work is to investigate supplying electric energy fromsolar-wind hybrid resources to remotely located communities detachedfrom the main grid line in Ethiopia. The communities in mind are one oftwo types; the first is the majority of the poor population residing in thecountryside; and the other is people relocated by the Government fromthe over used and dry regions to relatively productive and fertile ones inline with the long-term poverty reduction plan.The work was begun by investigating wind energy and solar energypotentials at four geographically different locations in Ethiopia bycompiling data from different sources and analyzing it using a softwaretool. The locations are Addis Ababa (09:02N, 038:42E), Mekele (13:33N,39:30E), Nazret (08:32N, 039:22E), and Debrezeit (8:44N, 39:02E).The results related to wind energy potential are given in terms of themonthly Average wind speed, the wind speed probability densityfunction (PDF), the wind speed cumulative density function (CDF), thewind speed duration curve (DC), and power density plots for all fourselected sites. According to the results obtained through the analysis, thewind energy potential, even if it is not exceptional, is irrefutably highenough to be exploited for generating electric energy.The solar energy potential, based on sunshine duration data collectedover a period of 7 - 11 years and radiation data obtained from differentsources, has been calculated using regression coefficients specific to thesites in question. Based on the sunshine duration data, the monthlyaverage daily sunshine amount for each of the places has also beencomputed and given in a form of plot. Through additional work on theresults of the calculations, the solar energy potential has been given inthe form of solar radiation plots for each of the selected sites. Asexpected, the results indicated an abundance of solar energy potential.It is based on the promising findings of these two energy resourcepotentials, wind and solar, that the feasibility study for a standalonesolar-wind hybrid energy supply system has proceeded, targeting thecommunity mentioned earlier. The hybrid system consisted of Windturbine, Photovoltaic panel, diesel generator and a bank of batteries, witha power conditioning converter included in the system.The hybrid standalone supply system is intended to provide electricity toa model community of 200 families with five to six family members ineach. The community is equipped with a primary load, a deferrable load,a community school and a health post. An electric load which includeslighting, water pumping, a radio receiver, and some clinical equipmenthas been suggested. Hybrid Optimization Model for ElectricRenewables, HOMER, software has been used for the analysis. Theaverage wind speed and average solar radiation calculated from the datafor all of the selected sites has been used to input into the software.The hybrid system design is approached in three different ways. The firstapproach is to include within the hybrid system those components whichare locally available, without giving special attention to their efficienciesand proceed with the design work. The second approach is tothoroughly search the market for the best and most efficienttechnological products and to select the best components for theanalysis. A third approach considered in an attempt of cost minimizationis to see if a self-contained type of design can be a better solution. Whatthis means is every household will have its own supply system that mayconsist of any combination of PV and wind turbine including converter,battery and charge controller.After running the simulations, lists of power supply systems have beengenerated, sorted according to their net present cost. Sensitivity variables,such as range of wind speeds, range of radiation levels and diesel pricehave been defined as inputs into the software and the optimizationprocess has been carried out repeatedly for the sensitivity variables andthe results have been refined accordingly. / QC 20100623

This paper aims to examine what the differences is between the three application types, native, hybrid and web. The main focus will be placed on the web app and investigate whether it could be an alternative to native and hybrid app. To explain what a web app has the capacity to do, a web app is created in wordpress. Web development is moving forward, which is obviously positive. The problem may be, however, for companies that come from a completely different industry and who wish to develop a new web solution for their company. A native app can be a very expensive investment and it is far from all companies that can pay this. This study wants to find out if a web app, could be an alternative to the native app. Furthermore, the report will examine what the possibilities are for a web app and what existing web apps there is today. Furthermore, a simple price comparison between the different app types to be made. / Den här rapporten syftar till att undersöka vad skillnaden är mellan de tre applikationstyperna, native, hybrid och webb. Störst fokus kommer att placeras på webb appen och undersöka om denna skulle kunna vara ett alternativ till native och hybrid appen. För att redogöra vad en webb app har kapacitet att göra kommer en webb app att skapas i wordpress. Webbutvecklingen går framåt vilket självklart är positivt. Problemet som kan bli är dock för företag som kommer från en helt annan bransch och som önskar ta fram en ny webb-lösning för sitt företag. En native app kan vara en väldigt dyr investering och det är långt ifrån alla företag som kan betala detta. Denna undersökning vill reda ut om en webb app kan var ett alternativ till native appen. Vidare kommer rapporten undersöka vad det finns för möjligheter för en webb app och vad det finns för webb appar idag. Dessutom kommer en enklare prisjämförelse mellan de olika apptyperna att göras.