This thesis has been performed in order to earn a master's degree in electrical engineering. The task was to implement an automatic voltage regulator, AVR, to control the terminal voltage of the synchronous generator Svante at the Division of Electricity at Uppsala University. The AVR uses Bluetooth technology to transfer a control signal produced by a programmable logical controller, PLC, to phase- mounted SSRs that decides what proportion of the AC from a six-phase brushless exciter that is to be used for the magnetization of the rotor. Test runs of the AVR were preformed with a regulator optimized according to the Ziegler-Nichols method and a static exciter that uses brushes and slip rings to apply voltage to the rotor winding. The results obtained complies with the assigned requirements set for this thesis and the AVR. The primary focus of this thesis mainly lies in the construction of the control system, which include the programming of both PLC and Bluetooth communicating devices.

Quantum key distribution (QKD) can provide unconditional security based on the fundamental laws of quantum physics. Unfortunately, real-life implementations of a QKD system may contain overlooked imperfections and thus violate the practical security of QKD. It is vital to explore these imperfections. In this thesis, I study two practical imperfections in QKD: i) Discovering security loophole in a commercial QKD system: I perform a proof-of-principle experiment to demonstrate a technically feasible quantum attack on top of a commercial QKD system. The attack I utilize is called phase-remapping attack. ii) Generating high-speed truly random numbers: I propose and experimentally demonstrate an ultrafast QRNG at a rate over 6 Gb/s, which is based on the quantum phase fluctuations of a laser. Moreover, I consider a potential adversary who has partial knowledge of the raw data and discuss how one can rigorously remove such partial knowledge with post-processing.

Quantum key distribution (QKD) can provide unconditional security based on the fundamental laws of quantum physics. Unfortunately, real-life implementations of a QKD system may contain overlooked imperfections and thus violate the practical security of QKD. It is vital to explore these imperfections. In this thesis, I study two practical imperfections in QKD: i) Discovering security loophole in a commercial QKD system: I perform a proof-of-principle experiment to demonstrate a technically feasible quantum attack on top of a commercial QKD system. The attack I utilize is called phase-remapping attack. ii) Generating high-speed truly random numbers: I propose and experimentally demonstrate an ultrafast QRNG at a rate over 6 Gb/s, which is based on the quantum phase fluctuations of a laser. Moreover, I consider a potential adversary who has partial knowledge of the raw data and discuss how one can rigorously remove such partial knowledge with post-processing.

Architectural research for Field-Programmable Gate Arrays (FPGAs) tends to use an experimental approach. The benchmark circuits are used not only to compare different architectures, but also to ensure that the FPGA is sufficiently flexible to implement the desired variety of circuits. The most common benchmark circuits used for architectural research are circuits from the Microelectronics Center of North Carolina (MCNC). These circuits are small; they occupy less than 3% [5] of the largest available commercial FPGA. Moreover, these circuits are more representative of the glue logic circuits that were targets of early devices. This contrasts with the trend towards implementing Systems on Chip (SoCs) on FPGAs where several functional modules are integrated into a single circuit which is mapped onto one device. In this thesis, we develop a synthetic system-level circuit generator that connects pre-existing circuits in a realistic manner to build large netlists that share the characteristics of real SoC circuits. This generator is based on a survey of contemporary circuit designs from industrial and academic sources. We demonstrate that these system-level circuits scale well and that their post-routing characteristics match the results of large pre-existing benchmarks better than the results of circuits from previous synthetic generators.

Generally urban drainage systems are built to protect urban property and control runoff. Moreover, these systems collect the runoff for storage purposes to serve society through sufficient water supply to meet the needs of demand, irrigation, and drainage. Urban environments are exposed to risks of extreme hydrological events. Therefore, urban water systems and their management are critical. Precipitation data are crucial, but may be prone to errors due to the lack of information e.g., short length of records. In this thesis, a Monte Carlo simulation and regional frequency analysis based on L-moments approach were utilized during the research in order to estimate the uncertainty in the Intensity Duration Frequency (IDF) curves by using historical precipitation data from Environment Canada (EC) weather stations and simulating a new series of data through a weather generator (WG) model. The simulations were then disaggregated from daily into hourly data for extraction of the annual maximum precipitation for different durations in hours (1, 2, 6, 10, 12, and 24). Regional frequency analysis was used to form the sites into groups based on homogeneity test results, and the quantile values were computed for various sites and durations with the return periods (T) in years (2, 10, 20, and 100). As a result, the regional frequency analysis was used to estimate the regional quantile values based on L-moment approach. Moreover, the box and whisker plots were utilized to display the results. When the return periods and durations increased, the uncertainty slightly increased. The historical IDF curves of London site falls within the regional simulated IDF curves. Furthermore, 1000 runs have been generated by using the weather generator.

Due to the insecurity of the supply of raw materials needed for neodymium-iron-boron magnets, typically used in permanent magnet generators, the use of ferrite magnets as an alternative was investigated. The investigation was conducted by attempting to redesign a generator that previously used neodymium-iron-boron magnets for use with ferrite magnets. The major part of the redesign was to find an alternate rotor design with an electromagnetic design adapted to the characteristics of the ferrite magnets.It was found that  ferrite magnets can be used to replace neodymium-iron-boron magnets with changes to the electromagnetic design of the rotor. The changes of the electromagnetic design increase the amount of magnetically active material in the rotor and, therefore, require the mechanical design of the rotor to be changed. The new rotor design also requires some changes to the generator support structure. A design for a replacement rotor, using ferrite magnets, along with the required changes to the support structure, is presented.

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A component is built to be reused and reusability has significant impact on component generality and flexibility requirement. A component model plays a critical role in reusability of software component and defines a set of standards for component implementation, evolution, composition, deployment and standardization of the run-time environment for execution of component. In component based development (CBD), standardization of the runtime environment includes specification of component’s interfaces – general and domain specific run-time services. For rapid development of component based system for distributed information systems, COM+ and .NET technologies introduced the idea of Software Component Services that are achieved by proxy objects which intercept message calls between components to provide service like transaction handling, security management, etc. An embedded real-time system (ERTS) designed for a specific purpose in which software tasks have hard real-time constraints to execute and it interact directly with its environment via buses, sensors and other devices. In an embedded real time system, it is great importance to ensure that all tasks of the software system should respond within the time limits. Component based development process have vital role in development of embedded real time system and recently software component models applied in the embedded real-time systems (ERTS) and introduced software component services (SCS) for ERTS. The purpose of this Master thesis is to investigate how to make tool that targets smart device projects in Microsoft Visual Studio and generates proxy objects that can be compiled with Microsoft Visual Studio.NET. The tool generates a complete set of files for a Microsoft Visual Studio smart device project within solution, including both source code and configuration files according to a specific version of Visual Studio by invoking Visual Studio’s automation object model. The tool also generates code for simple logging services for the .NET component running on top of the .NET Compact framework.

After enjoying one week in the Swedish Lapland, the idea of providing energy to one of those isolated cabins in the far landscape caught our attention. Nowadays, there still exist many dwellings, usually located in rural isolated sites, which have no easy access or even no possibility to get connected to the distribution and transport electricity grids. This situation may cause some inconvenience to the owners, therefore, the interest in finding new alternatives for supplying electricity. Such a problem requires specific solutions, including the development of electrification programs in those countryside isolated spots. Thus, the present project intends to perform a study which would provide the proper electric system to a summerhouse in the North of Sweden. Regarding the current European environmental politics and considering the rural location of the dwelling of study, the project will focus on various renewable alternatives to reach the above mentioned goal. In fact, Sweden has the greatest share of renewable energies in all European Union countries with a fixed goal of reaching 50% of its total energy production by renewable sources by the year 2020. For the present moment, Sweden already accounts for 9.4 GWh on solar energy production and 3.5 TWh on wind power production by the end of 2010. Therefore, the study will build on these alternatives as they represent two of the most extensively developed renewable possibilities in the country. Thereby, the first objective of the project was to determine a concrete location considering both our initial idea and the possibility of obtaining the wind speed and solar radiation data. A plot located 20 km to the north of Lulea was finally chosen. Then, once having the necessary baseline data comes the sizing of the different alternative: stand alone wind turbine system, stand alone PV system and a hybrid system combining wind power with the support of an electric generator. No option including grid connection is taken into consideration due to the lack of accessibility. Finally, it is performed an economic study of each alternative that would lead to a clear conclusion of which is the most appropriate choice in the study case. Economic criteria will therefore be the most significant factor when choosing the optimum alternative. However, environmental issues would also be taken into account. As no traditional electrification is studied, the economic analysis will not refer to the obtained monetary savings regarding to the grid connected option but will be performed by comparing initial investments. After all, it is concluded that the studied dwelling will be electrified by a hybrid system combining wind power with an electric generator. The system includes a 20 kW wind turbine and a diesel fueled generator with 8 kW power service. The generator will provide the required energy to the house during those days when the wind resource is not capable to cover the demand. Therefore, the lack of electricity supply will be avoided. Regarding investment costs of the chosen alternative, the hybrid system accounts for 20,729€ investment, which corresponds to about 40% the total price of both solar and wind stand alone systems. . Considering environmental criteria, the hybrid system only requires 23 diesel liters to be burned during the six summer months. Therefore, emissions due to combustion are relatively low and not considered as damaging. So, the chosen alternative meets both economical and environmental requirements.

In order to reduce the price for, and improve the performance of automatic control systems for magnetization of synchronus generators, the possibilities of using a PC based software PLC system, Programmable Logic Controller, has been investigated. The result is a system based on the CoDeSys software PLC with runtime environment from 3S-Software, communicating with external units via Modbus fieldbus. System price is reduced from €5000 to €2000 and system processing speed is reduced from 10 ms for a Siemens S7 PLC to 4 ms with the CoDeSys PLC system though unsolved problems with runtime seizure caused by improper settings in the PC BIOS.