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Verktyg som analyserar och detekterar problem på ett trefasnät kan spara tid och minska energiförbrukningen för industrin. Dagens utbud av trefasloggers har antingen ett mycket högt pris eller begränsad funktionalitet. Det här examensarbetet undersökte huruvida en prototyp för en trefaslogger med transientdetektering kunde produceras och säljas för under 4000 SEK. Arbetet innebar i huvudsak elektronikutveckling. Utifrån funktionsundersökningar planerades hårdvaran och komponenter valdes, varpå fullständigt kretsschema och PCB-ritning utvecklades. Resultatet visade att en trefaslogger med transientdetektering kunde tillverkas och säljas för cirka 3300 SEK inkluderat 25% försäljningsmarginal. Arbetet utfördes hos Motion Control i Västerås på efterfrågan av ABB Robotics. / Tools that can analyse and detect problems on a three-phase grid can save time and decrease energy consumption in the industry. The range of products available on today’s market either comes with a steep price, or limited functionality. This thesis examined the possibility of developing and producing a three-phase logger with transient detection, that could be sold for less than 4000 SEK including sales margin. The work mainly consisted of hardware development. The choice of hardware emanated from function analyses, whereupon a complete schematic and PCB-design was developed. The result showed that a three-phase logger with transient detection could be produced and sold for approximately 3300 SEK, including a 25 % sales margin. The thesis was done at Motion Control in Västerås at the request of ABB Robotics.

Zur Entwicklung eines effizienten Verfahrens zur CO2-Hydierung im Dreiphasensystem erfolgten in dieser Arbeit Untersuchungen zur Optimierung des Katalysatorsystems, zum Screening nach neuen geeigneten Lösungsmitteln und zum Einfluss der Prozessführung. Durch Variieren des Trägersystems und der Präparationsmethode ergaben sich sieben Kupferkatalysatoren, welche sich in ihren Eigenschaften und ihrer katalytischen Aktivität unterschieden. Zudem gelang die Immobilisierung von Kupferkatalysatoren auf Aluminiumoxid und auf Glas. Es wurde eine kontinuierliche Anlage mit Rieselbettreaktor entwickelt und in Betrieb genommen, welche die Durchführung der CO2-Hydrierung in Gasphase und im Dreiphasensystem bei bis zu 90 bar ermöglicht. Im Batchversuch zeigte sich der Einfluss der Lösungsmittel auf die Effizienz des Katalysators. Vielversprechende Lösungsmittel wurden dann zur Methanolsynthese im kontinuierlichen Prozess eingesetzt, um den Einfluss der Prozessbedingungen zu untersuchen.

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This thesis provides insight into state-of-the-art Modular Multilevel Converters (MMC) for medium and high voltage applications. Modular Multilevel Converters have increased in interest in many industrial applications, as they offer the following advantages: modularity, scalability, reliability, distributed location of capacitors, etc. In this study, the modeling, control and design considerations of modular based multilevel converters, with an emphasis on the reliability of the converter, is carried out. Both modular multilevel converters with half-bridge and full-bridge sub-modules are evaluated in order to provide a complete analysis of the converter. From among the family of modular based hybrid multilevel converters, the newly released Alternate Arm Converter (AAC) is considered for further assessment in this study. Thus, the modular multilevel converter with half-bridge and full-bridge power cells and the Alternate Arm Converter as a commercialized hybrid structure of this family are the main areas of study in this thesis. Finally, the DC fault analysis as one of the main issues related to conventional VSC converters is assessed for Modular Multilevel Converters (MMC) and the DC fault ride-through capability and DC fault current blocking ability is illustrated in both the Modular Multilevel Converter with Full-Bridge (FB) power cells and in the Alternate Arm Converter (AAC). Accordingly, the DC fault control scheme employed in the converter and the operation of the converter under the fault control scheme are explained. The main contributions of this study are as follows: The new D-Q model for the MMC is proposed for use in the design of the inner and outer loop control. The extended control scheme from the modular multilevel converter is employed to control the Alternate Arm Converters. A practical reliability-oriented sub-module capacitor bank design is described based on different reliability modeling tools. A Zero Current Switching (ZCS) scheme of the Alternate Arm Converter is presented in order to reduce the switching losses of the Director Switches (DS) and, accordingly, to implement the ZCS, a design procedure for the Arm inductor in the AAC is proposed. The capacitor voltage waveform is extracted analytically in different load power factors and the waveforms are verified by simulation results. A reliability-oriented switching frequency analysis for the modular multilevel converters is carried out to evaluate the effect of the switching frequency on the MMC's operation. For the latter, a DC fault analysis for the MMC with Full-Bridge (FB) power cells and the AAC is performed and a DC fault control scheme is employed to provide the capacitor voltage control and DC fault current limit, and is illustrated herein. / Master of Science

This work investigates communication issues in high-frequency power converters. A novel control communication network (Power Electronics System Network or PES Net) is proposed for modular, medium and high-power, converters. The network protocol, hardware and software are designed and implemented. The PES Net runs at 125 Mb/s over plastic optical fiber allowing converter switching frequencies in excess of 100 kHz. Communication control is implemented in a field programmable gate array device. A novel synchronization method applicable to ring networks is proposed. The effect of the communication delay on the power converter operation is studied. / Master of Science

The aim of this thesis was to study RWCT methods used at the beginning of a school attendance and to study appropriate conditions for applying RWCT methods. The thesis deals with searching for the best method of the very initial pupils reading and also appropriate teaching materials with regard to RWCT. There is described a three-phase model of E-U-R education and selected method of critical thinking. The practical part of the thesis contains preparation for lessons processed using RWCT methods and summarizes results of pedagogical action research. The outcomes of the thesis confirm that if pupils have suitable conditions at the beginning of a school attendance, they are able to use RWCT methods in practise.