La topologie onduleur à six bras associé à une machine triphasée à phases indépendantes a la propriété de d'offrir, dans le cadre applicatif de l'automobile, une double fonctionnalité, traction et chargeur forte puissance. Cet avantage nécessite, par contre, le contrôle des composantes homopolaires classiquement nulles lors de la présence d'un couplage en étoile. Cette thèse propose alors, d'une part une étude et une modélisation des onduleurs multi-bras et, d'autre part, développe des stratégies de contrôle-commande adaptées à la présence des grandeurs homopolaires. Les algorithmes de commande classiques de l'onduleur sont comparés et une stratégie vectorielle originale, dite Z-SVM permettant d'annuler le courant homopolaire haute fréquence, est développée. Enfin, il est montré comment la gestion des composantes homopolaires aux valeurs moyennes permet d'accroître les performances de l'ensemble à faible comme à haute vitesse, en jouant sur les zones avant et après défluxage des caractéristiques couple-vitesse. Les solutions proposées sont validées sur un banc expérimental composé d'une machine prototype spécialement développée pour une application automobile et alimentée par un onduleur six-bras commandé par des composants de type FPGA. Les stratégies proposées sont comparées en termes de performances et de complexité algorithmique. / For an automotive application, a six leg-VSI connected to a three-phase open-end winding machine has the ability to offer a dual-function. In this case, an additional zero-sequence component, usually absent when a star-coupling is used, needs to be controlled. Firstly, a study, modeling and control of a multi-leg inverter are proposed. Secondly, control structures capable of handling the presence of zero-sequence components are investigated. The conventional control algorithms applied to the inverter are analyzed and an original vector control strategy, called Z-SVM, capable to cancel the high frequency zero-sequence current is developed. Finally, it is shown how the management of the zero-sequence components enhances the performance of the drive at low as well as at high-speed, corresponding on the areas of the torque-speed characteristics before and after flux weakening. The proposed solutions are validated on an experimental test bench consisting of a machine prototype especially developed for automotive application and powered by a six-leg inverter controlled by an FPGA-based device. The proposed strategies are compared in terms of performance and computational complexity.

Multilevel voltage source inverters have been receiving more and more attention from the industry and academia as a choice for high voltage and high power applications. The high voltage multilevel inverters can be constructed with existing low voltage semiconductor switches, which already have a mature technology for handling low voltages, thus improving the reliability of the overall inverter system. These multilevel inverters generate the output voltage in the form of multi-stepped waveform with smaller amplitude. This will result in less dv/dt at the motor inputs and electromagnetic interference (EMI) caused by switching is considerably less. Because of the multi-stepped waveform, the instantaneous error in the output voltage will be always less compared to the conventional two-level inverter output voltage. It will reduce the unwanted harmonic content in the output voltage, which will enable to switch the inverter at lower frequencies. Many interesting multi level inverter topologies are proposed by various research groups across the world from industry and academic institutions. But apart from the conventional 3-level NPC and H-bridge topology, others are not yet highly preferred for general high power drives applications. In this respect, two different five-level inverter topologies and one three-level inverter topology for high power induction motor drive applications are proposed in this work. Existing knowledge from published literature shows that, the three-level voltage space vector diagram can be generated for an open-end winding induction motor by feeding the motor phase windings with two two-level inverters from both sides. In such a configuration, each inverter is capable of assuming 8 switching states independent of the other. Therefore a total of 64 switching combinations are possible, whereas the conventional NPC inverter have 27 possible switching combinations. The main drawback for this configuration is that, it requires a harmonic filter or isolated voltage source to suppress the common mode currents through the motor phase winding. In general, the harmonic filters are not desirable because, it is expensive and bulky in nature. Some topologies have been presented, in the past, to suppress the common mode voltage on the motor phase windings when the both inverters are fed with a single voltage source. But these schemes under utilize the dc-link voltage or use the extra power circuit. The scheme presented in chapter-3 eliminates the requirement of harmonic filter or isolated voltage source to block the common mode current in the motor phase windings. Both the two-level inverters, in this scheme, are fed with the same voltage source with a magnitude of Vdc/2 where Vdc is the voltage magnitude requires for the NPC three-level inverter. In this scheme, the identical voltage profile winding coils (pole pair winding coils), in the four pole induction motor, are disconnected electrically and reconnected in two star groups. The isolated neutrals, provided by the two star groups, will not allow the triplen currents to flow in the motor phase windings. To apply identical fundamental voltage on disconnected pole pair winding, decoupled space vector PWM is used. This PWM technique eliminates the first center band harmonics thereby it will allow the inverters to operate at lower switching frequency. This scheme doesn’t require any additional power circuit to block the triplen currents and also it will not underutilize the dc-bus voltage. A five-level inverter topology for four pole induction motor is presented in chapter-3. In this topology, the disconnected pole pair winding coils are effectively utilized to generate a five-level voltage space vector diagram for a four pole induction motor. The disconnected pole pair winding coils are fed from both sides with conventional two-level inverters. Thereby the problems like capacitor voltage balancing issues are completely eliminated. Three isolated voltage sources, with a voltage magnitude of Vdc/4, are used to block the triplen current in the motor phase windings. This scheme is also capable of generating 61 space vector locations similar to conventional NPC five-level inverter. However, this scheme has 1000 switching combinations to realize 61 space vector locations whereas the NPC five-level inverter has 125 switching combinations. In case of any switch failure, using the switching state redundancy, the proposed topology can be operated as a three-level inverter in lower modulation index. But this topology requires six additional bi-directional switches with a maximum voltage blocking capacity of Vdc/8. However, it doesn’t require any complicated control algorithm to generate the gating pulses for bidirectional switches. The above presented two schemes don’t require any special design modification for the induction machine. Although the schemes are presented for four pole induction motor, this technique can be easily extend to the induction motor with more than four poles and thereby the number of voltage levels on the phase winding can be further increased. An alternate five-level inverter topology for an open-end winding induction motor is presented in chapter-4. This topology doesn’t require to disconnect the pole pair winding coils like in the previous propositions. The open-end winding induction motor is fed from one end with a two-level inverter in series with a capacitor fed H-bridge cell, while the other end is connected to a conventional two-level inverter to get a five voltage levels on the motor phase windings. This scheme is also capable of generating a voltage space vector diagram identical to that of a conventional five-level inverter. A total of 2744 switching combinations are possible to generate the 61 space vector locations. With such huge number switching state redundancies, it is possible to balance the H-bridge capacitor voltage for full modulation range. In addition to that, the proposed topology eliminates eighteen clamping diode having different voltage ratings compared to the NPC inverter. The proposed topology can be operated as a three-level inverter for full modulation range, in case of any switch failure in the capacitor fed H-bridge cell. All the proposed topologies are experimentally verified on a 5 h.p. four pole induction motor using V/f control. The PWM signals for the inverters are generated using the TMS320F2812 and GAL22V10B/SPARTAN XC3S200 FPGA platforms. Though the proposed inverter topologies are suggested for high-voltage and high-power industrial IM drive applications, due to laboratory constraints the experimental results are taken on the 5h.p prototypes. But all the proposed schemes are general in nature and can be easily implemented for high-voltage high-power drive applications with appropriate device ratings.

Tato diplomová práce se zabývá revizí elektroniky robotického vozidla car4 se zaměřením na měření rychlosti otáčení kol, výkonovou a řídicí elektroniku. Car4 posloužilo jako základ pro již přes 20 diplomových prací od roku 2010. To znamenalo, že některé základní aspekty car4 byly zastaralé. Bylo vytvořeno schéma elektroniky vozidla, které bylo dále využito pro vývoj a výrobu nového hardwaru. Komponenty byly poté otestovány a implementovány na vozidlo. Dále byl vytvořen kinematický model 4WS vozidla za použití Ackermanovy geometrie, který byl implenetován a otestován na car4. Dále by měl sloužit jako základ řídicího algoritmu pro budoucí vývoj car4.

This project deals with comparing types and properties of commercial produced incubators for exotic birds. It searches the best solution from these area. In this project are compars individual components and their choice for realization in this project. Then in this project is solution of regulation temperature and humidity in engineered mechanism and discovered parameters of specifically space. Then is developed solution of thermostat and hydrosatat for this prototype. Temperature is changed by Peltier module, who is involved in correct system. Humidity is regulated by resistor humidifier. Complex system is managed by microcontroler. System communicates with PC via USB interface and Ethernet. Solution of this project is maked functional prototyp.

This diploma thesis is a part of a project of two students. The aim of the project is to design safer electronics for the unstable balancing vehicle HUMMER and implementation of advanced diagnostics and fault detection. In the first part of the project we analysed the original vehicle using the FMEA analyse and created a new concept of the vehicle. The second part of the project describes a new hardware. I designed and tested the power electronics, control unit and supplies. The outputs of the work are prototypes which allow testing a new concept.

This diploma thesis deals with a design and construction of a two-wheeled mobile robot. In order to prepare a high-quality project, a testing carriage has been constructed serving as a basis of useful information for the final design and construction. Beside introduction and conclusion, the diploma thesis consists of four main parts. While the first part of the thesis briefly introduces the field of robotics, the theoretical part focuses both on particular components necessary for the robot's construction as well as the Segway vehicle which served as an inspiration for the robot's functionality. After characteristics of a testing carriage, attention is devoted to individual methods of stabilization, with several different types of sensors being used. Furthermore, the chapter on mechanical design examines choice of devices and their position and provides a scheme for their construction. The electrical design follows afterwards, describing circuits that were considered optimal for the designed wiring. The forth part of the diploma thesis concentrates on the construction of a two-wheeled carriage and covers following topics: construction of mechanical components, production of electric boards, programmatic equipment of the carriage and its implementation, testing of the carriage and finally also an evaluation of achieved results.

Customized truck is a relevant and high-profit part of Scania’s market. Nowadaysdesigners do not have a self-developed electric control unit for introducing non-standardfunctionality. This thesis is intended to investigate the specification of a new system andan approach to implement it in current truck’s electrical system. The adopted methodsin this research are systems analysis, functional specification, HW & SW research andcomparison and validation test of prototype system. The results obtained in this researchinclude the potential functions and corresponding requirement specification, 5 types ofhardware alternatives and 2 recommended software platform. Their feasibility is verifiedby a prototype system with 2 typical functions, control the motor of inward sliding doorand combine the communication of different system. 3 recommended schemes and 2 directionsfor future research are given in the end. Based on investigation results, developersare able to know new system’s specification preliminarily, understand the architectural requirementsand suitable tools and materials for implementation. This research will helpto improve Scania’s truck’s electrical system and product manufacturing in the future. / Specialfordon utgör en viktig och betydande del av Scanias produkter. Dagens de-signer har inte tillgång till en egenutvecklad styrenhet för att introducera icke standardiserade funktioner. Detta examensarbete fokuserar på att undersöka ett nytt system och hur det skulle implementeras i den redan existerande lastbilens elektriska system. De behandlade ämnena i arbetet är systemanalys, funktionsanalys, hårdvaruspecifikation, mjukvara samt validering och utvärdering i form av byggnation och testning av en prototyp. Resultatet som erhållits i denna rapport inkluderar potentiella funktioner och motsvarande kravspecifikation, fem typer av hårdvara och tvårekommenderade mjukvaruplattformar. Reliabiliteten av dessa valideras med en prototyp med två typiska funktioner, kontrolleraen motor på en elektrisk dörr samt kombinera kommunikationen av olika system. Trealternativa lösningar samt två alternativ till framtida studier rekommenderas i slutet av rapporten. Baserat på resultaten har utvecklare möjlighet till en preliminär specifikation,förståkrav påarkitektur, användbara verktyg och material för implementation. Dennarapport kommer att underlätta förbättring av Scanias elektriska system och utveckling iframtiden.

The purpose of this project is to design and construct a portable lightweight elevator for transportation of goods to rooftops. The elevator should be easy to transport, assemble and disassemble, it should also be useful at various heights and for a wide range of roof inclinations. The elevator contains a railway consisting of four separable modules. A carriage rides the railway and is pulled to the top with a winch powered by a DC-motor. The carriage starts and stops using a Rocker switch and a Hall sensor that detects magnets placed at the end and beginning of the railway. After performing tests with the elevator the conclusion is that the elevator is practical to assemble and transport, but the carriage derails too easily when the railway has angular changes. / Målet med projektet är att designa och konstruera en portabellättviktshiss som kan transportera gods från marknivå till hustak. Den ska vara lätt att transportera och att montera ner och upp, den ska också gå att anvåanda för olika höjder och på hus med olika taklutningar. Hissen består av en räls som går att ta isär i fyra olika delar. En vagn åker på fyra hjul uppför rälsen och lyftkraften kommerfrån en vinsch som drivs av en likströmsmotor. Vagnen kan starta och stanna med hjälp av en knapp, den stannar även automatisk då en hallsensor på vagnen känner av magneter som är placerade vid början och slutet av rälsen. En arduino Uno skickar signaler mellan de elektriska komponenterna och motorn får ström via en H-brygga, vilket gör att den kan rotera i båda riktningarna. Efter att hissen testats kan det konstateras att konstruktionen är enkel att bygga ihop och smidig att fästa vid olikavinklar och höjder. Däremot spårar vagnen ofta ur då hissen körs med för branta vinklar mellan de olika delarna av rälsen.

For decades, the Silicon-based semiconductors have been the solution for power electronics applications. However, these semiconductors have approached their limits of operation in blocking voltage, working temperature and switching frequency. Due to material superiority, the relatively-new wide-bandgap semiconductors such as Silicon-Carbide (SiC) MOSFETs enable higher voltages, switching frequencies and operating temperatures when compared to Silicon technology, resulting in improved converter specifications. The current study tries to investigate the impact of emerging medium-voltage SiC MOSFETs on industrial motor drive application, where over a quarter of the total electricity in the world is being consumed. Firstly, non-commercial SiC MOSFETs at 3.3 kV and 400 A rating are characterized to enable converter design and simulation based on them. In order to feature the best performance out of the devices under test, an intelligent high-performance gate driver is designed embedding required functionalities and protections. Secondly, total of three converters are targeted for industrial motor drive application at medium-voltage and high-power range. For this purpose the cascaded H-bridge, the modular multilevel converter and the 5-L active neutral point clamped converters are designed at 4.16-, 6.9- and 13.8 kV voltage ratings and 3- and 5 MVA power ratings. Selection of different voltage and power levels is done to elucidate variation of different parameters within the converters versus operating point. Later, comparisons are done between the surveyed topologies designed at different operating points based on Si IGBTs and SiC MOSFETs. The comparison includes different aspects such as efficiency, power density, semiconductor utilization, energy stored in converter structure, fault containment, low-speed operation capability and parts count (for a measure of reliability). Having the comparisons done based on simulation data, an H-bridge cell is implemented using 3.3 kV 400 A SiC MOSFETs to evaluate validity of the conducted simulations. Finally, a novel method is proposed for series-connecting individual SiC MOSFETs to reach higher voltage devices. Considering the fact that currently the SiC MOSFETs are not commercially available at voltages higher above 1.7 kV, this will enable implementation of converters using medium-voltage SiC MOSFETs that are achieved by stacking commercially-available 1.7 kV MOSFETs. The proposed method is specifically developed for SiC MOSFETs with high dv/dt rates, while majority of the existing solutions could only work merely with slow Si-based semiconductors. / Ph. D.

The DC-side floating capacitors in the floating power modules of power converters are subject to high voltage fluctuation, due to the presence of reactive harmonic components. Utilizing passive capacitors, as done in traditional methods, helps reduce the DC-bus voltage ripple but makes the system bulky. An active capacitor can be integrated with the floating H-bridge power modules to remove the effect of the ripple powers on the DC bus. The auxiliary circuit, which is much smaller in size compared to an equivalent passive capacitor, helps increase the power density of the system. This work focuses on the analysis of power components, and the extension of the active capacitor to the Perturbation Injection Unit (PIU), in which the DC side is highly distorted by multiple harmonic components. A control scheme is proposed to compensate for these multiple harmonics and balance the DC-link voltage in the active capacitor. Also, an equivalent DC-bus impedance model is introduced, which is more accurate than that in existing works. Simulation studies and evaluation of the design have verified the effectiveness of the active capacitor solution. / Single-phase power converters have been widely used in many applications such as electric vehicles, photovoltaic (PV) systems, and grid integration. Due to their popular application, there is a need to reduce the sizes and volumes while still maintaining good performances of the systems. One of the most effective methods, which is a subject in many research works, is to replace the bulky passive capacitor bank in a system by an active capacitor. The active capacitor is designed to absorb the ripple components in the DC side of the converters, which results in a constant DC-link voltage. In comparison to the passive capacitor solution, the active capacitor is much smaller in size but can give a better DC-bus ripple performance. Therefore, the active capacitor has become an attractive solution for the single-phase converters. The active capacitor for the traditional rectifier, where the DC side is directly connected to a load, has been intensively investigated in the past decade. However, there is limited research regarding the active capacitor for rectifiers with floating H-bridge power modules. This work extends the application of the active capacitor to the Perturbation Injection Unit (PIU), which is a grid-connected single-phase rectifier with floating H-bridge power modules. The selection of a suitable active capacitor for the PIU is based on the evaluation of various active capacitor banks. Limits in existing control schemes, which prevent the extension of the active capacitor to the PIU, are thoroughly studied. An effective voltage-mode control scheme is then proposed for the selected active capacitor, which makes it an attractive solution for the PIU. Moreover, limits of the DC-bus impedance analysis using traditional assumptions in existing works are investigated, and an improved DC-bus impedance model is proposed. Based on the operation conditions of the PIU and the proposed impedance model, the active capacitor's components can be properly designed, and improved configurations in terms of the equivalent impedance can be analyzed. Simulation results, as well as the design and evaluation of the active capacitor, demonstrate great improvements in terms of volume and weight over the traditional passive capacitor bank.