In the modern generation, Electric Power has become one of the fundamental needs for humans to survive. This is due to the dependence of continuous availability of power. However, for electric power to be available to the society, it has to pass through a number of complex stages. Through each stage power quality problems are experienced on the grid. Under-voltages and over-voltages are the most common electric problems experienced on the grid, causing industries and business firms losses of Billions of dollars each year. Researchers from different regions are attracted by an idea that will overcome all the electrical issues experienced in the traditional grid using Artificial Intelligence (AI). The idea is said to provide electric power that is sustainable, economical, reliable and efficient to the society based on Evolutionary Algorithms (EAs). The idea is Smart Grid. The research focused on Power Quality Optimization in Smart Grid based on improved Differential Evolution (DE), with the objective functions to minimize voltage swells, counterbalance voltage sags and eliminate voltage surges or spikes, while maximizing the power quality. During Differential Evolution improvement research, elimination of stagnation, better and fast convergence speed were achieved based on modification of DE’s mutation schemes and parameter control selection. DE/Modi/2 and DE/Modi/3 modified mutation schemes proved to be the excellent improvement for DE algorithm by achieving excellent optimization results with regards to convergence speed and elimination of stagnation during simulations. The improved DE was used to optimize Power Quality in smart grid in combination with the reconfigured and modified Dynamic Voltage Restorer (DVR). Excellent convergence results of voltage swells and voltage sags minimization were achieved based on application of multi-objective parallel operation strategy during simulations. MATLAB was used to model the proposed solution and experimental simulations. / Electrical and Mining Engineering / M. Tech. (Electrical Engineering)

Inductive power transmission is very useful, not only for systems where energy transfer should take place in hazardous, humid and wet areas, but also for mobile and very small systems. It finds today a widespread use in several fields, such as industry, automotive, medicine and smart buildings. For a good efficiency and a high-power transmission, the sending and the receiving coils should be perfectly aligned and close to each other. A misalignment between the sender and the receiver becomes unavoidable especially for systems with movable parts. This thesis aims to improve the transmitted power, the mutual inductance, the power at the load, and consequently the power transmission efficiency in case of lateral misalignment between the sending and receiving coils and at large coil-to-coil distance. For this purpose, we adopt a multi input single output (MISO) coil system able to orientate the issued magnetic field to the receiving coil by powering the neighbouring sending coils of the active ones with a weak current in the opposite direction. Furthermore, an analytical model of the used coils and an accurate three-dimensional model of the system have been developed to calculate the induced voltage, the induced current, and the equivalent mutual inductance. Both simulation and experimental results prove that the proposed multi-coil inductive system having an hexagonal arrangement and the sending coils, which have the half diameter of the receiving coil, is able to improve significantly the transmitted power in case of lateral misalignment and big air gap. The novel MISO system reaches better efficiency beginning with an air gap of 50% of the sending coil diameter, and a misalignment of 28% of the sending coil diameter. It reaches the double of the transmitted power of the conventional two-coil inductive system at 50 mm air gap (corresponding to 166% of the sending coil diameter) and at 10 mm lateral misalignment (corresponding to 33% of the sending coil diameter). In order to improve the equivalent mutual inductance between the primary and secondary sides and to avoid energy losses, we propose a receiver detection method using the sending coils themselves as detectors. Thereby, only the sending coils, under the receiver, are activated and the others remain switched off. For that, the peak of the AC current of the sending coils, is measured and then compared to a detection threshold. The excitation strategy of the active sending coils is optimized corresponding to the receiving coil position. The novel excitation strategy increases the mutual inductance by 85% and the induced voltage by 13% at perfect alignment and by 30% and 10% respectively at 10 mm lateral misalignment, in comparison to the MISO system without a receiver detector and coil-excitation strategy. In order to increase the transmitted power by resonance, different system topologies have been investigated, such as series-series SS, series-parallel SP, parallel-series PS, and parallel-parallel PP topologies for different levels of load impedance. The results show that a multi-coil inductive system with parallel-parallel PP topology realizes a higher transmitted power than the other topologies for both high and low load impedance values. The proposed multi-coil inductive system is suitable for low-power systems, such as wireless sensors and biomedical implants, but can be also applied to higher range of power at a flexible position of the receiver. / Die induktive Energieübertragung ist interessant, nicht nur für Systeme, bei denen die Energieübertragung in rauen, feuchten und nassen Bereichen erfolgen soll, sondern auch für mobile und sehr kleine Systeme. Diese Art von Energieübertragung findet heute eine breite Anwendung in verschiedenen Bereichen, wie z.B. Industrie, Automobil, Medizin und intelligente Gebäude. Um eine gute Effizienz und eine hohe Energieübertragungsleistung zu realisieren, sollten die Sende- und Empfangsspulen perfekt ausgerichtet und nahe beieinander sein. Insbesondere bei Systemen mit beweglichen Teilen ist jedoch eine Fehlausrichtung zwischen Sender und Empfänger unvermeidlich. Diese Arbeit zielt darauf ab, die übertragene Leistung, die gegenseitige Induktivität, die Leistung an der Last und damit den Wirkungsgrad der Leistungsübertragung im Falle einer seitlichen Fehlausrichtung zwischen Sende- und Empfangsspule und bei großem Abstand von Spule zu Spule zu verbessern. Zu diesem Zweck wird ein Multi-Input Single-Output (MISO)-Spulensystem vorgeschlagen, das in der Lage ist, das ausgegebene Magnetfeld auf die Empfangsspule auszurichten, indem die benachbarten Spulen der aktiven Sendespulen mit einem schwachen Strom in der entgegengesetzten Richtung versorgt wird. Darüber hinaus wurde ein analytisches Modell für die verwendeten Spulen und ein genaues dreidimensionales Modell für das System entwickelt, um die induzierte Spannung, den induzierten Strom und die äquivalente gegenseitige Induktivität zu berechnen. Sowohl die Simulation als auch die experimentellen Ergebnisse belegen, dass das vorgeschlagene induktive Mehrfachspulensystem mit hexagonaler Anordnung und die Sendespulen, die den halben Durchmesser der Empfangsspule haben, in der Lage sind, die Sendeleistung bei lateraler Fehlausrichtung und großem Luftspalt deutlich zu verbessern. Das neuartige MISO-System erreicht einen besseren Wirkungsgrad, beginnend mit einem Luftspalt von 50% des Sendespulendurchmessers und einer Fehlausrichtung von 28% des Sendespulendurchmessers. Sie erreicht bei 50 mm Luftspalt (entspricht 166% des Sendespulendurchmessers) und bei 10 mm seitlichem Versatz (entspricht 33% des Sendespulendurchmessers) das Doppelte der Sendeleistung des herkömmlichen Zwei-Spulen-Induktivsystems. Um die äquivalente gegenseitige Induktivität zwischen Primär- und Sekundärseite zu verbessern und Energieverluste zu vermeiden, schlagen wir ein Verfahren zur Detektion des Empfängers vor, bei dem die Sendespulen selbst als Detektoren verwendet werden. Dabei werden nur die Sendespulen unter dem Empfänger aktiviert und die anderen bleiben ausgeschaltet. Dazu wird der Scheitelwert des Wechselstroms der Sendespulen gemessen und mit einem vorgegebenem Schwellenwert verglichen. Die Anregungsstrategie der aktiven Spulen wird entsprechend der Position der Empfangsspule optimiert. Die neuartige Anregungsstrategie erhöht die gegenseitige Induktivität um 85% und die induzierte Spannung um 13% bei perfekter Ausrichtung und um 30% bzw. 10% bei 10 mm seitlichem Versatz, im Vergleich zum MISO-System ohne Empfängerdetektor und Spulenanregungsstrategie. Um die übertragene Leistung durch Resonanz zu erhöhen, wurden verschiedene Systemtopologien untersucht, wie z.B. Serien-SS, Serien-Parallel-SP, Parallel-Series-PS und Parallel-Parallel-PP-Topologien für verschiedene Stufen der Lastimpedanz. Die Ergebnisse zeigen, dass ein MISO System mit parallel-paralleler PP-Topologie eine höhere Sendeleistung realisiert als die anderen Topologien für hohe und niedrige Last-Impedanzen. Das vorgeschlagene induktive Mehrspulensystem eignet sich für Systeme mit geringer Leistung, wie drahtlose Sensoren und biomedizinische Implantate, kann aber auch flexibler Position des Empfängers in einen höheren Leistungsbereich angewendet werden.

Die Arbeit befasst sich mit einem neuen textilverstärkten Zugmittel mit formschlüssiger Krafteinleitung. Im Grundlagenteil werden Aufbau, Eigenschaften und Dimensionierungsgrundlagen von Rollenketten und Zahnriemenantrieben erörtert, sowie textile und elastomere Werkstoffe betrachtet. Aus den Betrachtungen zum Stand der Technik, der Maschenware mit hochfesten Filamentgarnen und deren polymeren Beschichtungen wird der Entwicklungsansatz abgeleitet. Mit Hilfe eines Spezialkettenwirkverfahrens werden die textilen Zugträger als Recht/Links-Maschenware hergestellt. Das besondere daran ist die teilungsgenaue Einbindung der Bolzen in die Maschenstruktur bei der Fertigung. Eine anschließende elastomere Beschichtung verbessert die mechanischen Eigenschaften erheblich und fixiert die Bolzen axial. Dabei werden reaktive Polyurethane im Gießverfahren und thermoplastische Elastomere im Spritzgießverfahren eingesetzt. Drei ausgewählte textile Bindungen mit verschiedenen Beschichtungen wurden statisch und dynamisch, anhand von Proben und endlos verbundenen Zugmitteln, ausführlich untersucht. Die daraus abgeleiteten Bauteil-Wöhlerlinien und Leistungsdiagramme bilden die Grundlage zur Auslegung der textilverstärkten Zugmittel für Anwendungen im Maschinenbau. / The dissertation deals with a new textile reinforced with form-closed force application. The basis of structure, properties and sizing basics of roller chain drives and belt drives are discussed and considered textile and elastomeric materials. From consideration of the prior art, the knitted fabric with high tenacity filament of polymeric coatings and their development approach is derived. Using a special knitting process, the textile chain tension members are produced as a right / left-knit fabric. The special thing about it is the exact distribution of involvement of the pins in the mesh structure during manufacturing. Subsequent elastomeric coating significantly improves the mechanical properties and fixes the bolt axially. These reactive polyurethanes by casting and thermoplastic elastomers are used in injection molding. Three selected textile bonds with different coatings were statically and dynamically examine in detail the basis of samples and associated endless traction means. The derived component S/N curves and performance charts are the basis for the design of textile-reinforced tension means for applications in mechanical engineering.

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<p dir="ltr">The urgent global shift towards decarbonization necessitates the development of robust frameworks to navigate the complex technological, financial, and regulatory challenges emerging in the clean energy transition. Furthermore, the increased adoption of renewable energy sources (RES) is correlated to the exponential growth in weather data research over the last few years. This circular relationship, where big data drives renewable growth, which feeds back the data pipeline, serves as the primary focus of this study: the development of computational tools across diverse spatial and temporal scales for the optimal design and operation of renewable energy-based systems. Two scales are considered, differentiated by their primary objectives and techniques used. </p><p dir="ltr"> In the first one, the integration of probabilistic forecasts into the operations of RES microgrids (MGs) is studied in detail. It is revealed that longer scheduling horizons can reduce dispatch costs but at the expense of forecast accuracy due to increased prediction accuracy decay (PAD). To address this, a novel method that determines how to split the time horizon into timeblocks to minimize dispatch costs and maximize forecast accuracy is proposed. This forms the basis of an optimal rolling horizon strategy (ORoHS) which schedules distributed energy resources over varying prediction/execution horizons. Results offer Pareto-optimal fronts, showing the trade-offs between cost and accuracy at varying confidence levels. Solar power proved more cost-effective than wind power due to lower variability, despite wind’s higher energy output. The ORoHS strategy outperformed common scheduling methods. In the case study, it achieved a cost of \$4.68 compared to \$9.89 (greedy policy) and \$9.37 (two-hour RoHS). The second study proposes the Caribbean Energy Corridor (CEC) project, a novel, ambitious initiative that aims to achieve total grid connectivity between the Caribbean islands. The analysis makes use of thorough data procedures and optimization methods for the resource assessment and design tasks needed to build such an infrastructure. Renewable energy potentials are quantified under different temporal and spatial coverages to maximize usage. Prioritizing offshore wind development, the CEC’s could significantly surpass anticipated growth in energy demand, with an estimated installed capacity of 34 GW of clean energy upon completion. The corridor is modeled as an HVDC grid with 32 nodes and 31 links. Underwater transmission is optimized with a Submarine-Cable-Dynamic-Programming (SCDP) algorithm that determines the best routes across the bathymetry of the region. It is found that the levelized cost of electricity remains on the low end at \$0.11/kWh, despite high initial capital investments. Projected savings reach \$ 100 billion when compared with ”business-as-usual” scenarios and the current social cost of carbon. Furthermore, this infrastructure has the potential to create around 50,000 jobs in construction, policy, and research within the coming decades, while simultaneously establishing a robust and sustainable energy-water nexus in the region. Finally, the broader implications of these works are explored, highlighting their potential to address global challenges such as energy accessibility, prosperity in conflict zones, and sharing these discoveries with the upcoming generations.</p>