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Traction Drives with Asynchronous Motors
Běloušek, Josef ; Skala, Bohumil (referee) ; Richter, Aleš (referee) ; Patočka, Miroslav (advisor)
The first part of this work is devoted to the design of a traction asynchronous motor. The second part focuses on the developed method of the equivalent circuit parameters identification of the asynchronous motor in the form of -network. It is explained here that the equivalent circuit in the shape of a -network, alternatively of an inverse 'I-network, is exactly equivalent and fully-fledged to a T-network, although one of two stray inductances is formally missing. Furthermore, the relationships for the conversions of the T-network parameters to the -network parameters and back, and of the T-network to the inverse 'I-network and back are found. The third part deals with the calculation of the torque and the current characteristics of the asynchronous motor. A sensitive analysis of the torque characteristic is carried out on the individual parameters of the equivalent circuit of the asynchronous motor in the form of a -network and a method of the measurement by means of a flywheel is used for the torque characteristic measurement of the asynchronous motor. The fourth part focuses on the verification of the identified -network parameters in the Matlab-model of the traction drive.
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Losses Analysis in Electric Machines under Special Conditions
Bulín, Tomáš ; Rafajdus, Pavol (referee) ; Skala, Bohumil (referee) ; Ondrůšek, Čestmír (advisor)
This thesis deals with the analysis of magnetic losses in electrical machines and the possibilities of their measurement. Magnetically soft and hard materials are very prone to changing magnetic properties. They can be changed simply by changing the temperature of the material or different stresses induced in the material, resulting in different results. These changes are important to keep in mind when an electric machine is being designed. The original parameters of the affected materials can be restored by annealing or grinding. These methods release the induced stresses within the material. Due to these effects, it is also important to know how to measure magnetic parameters. Each way has its own specifics and has a certain error of the measurement. When the machines for higher efficiency, rpm or higher temperatures are designed, it is advisable to know how their magnetic properties changed. This thesis deals with the properties of different materials, their measurements and finally simulation of the chosen electric machine with the application of the measured results.
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Fault-Tolerant Control of a Flux-switching Permanent Magnet Synchronous Machine
Aboelhassan, Mustafa Osman Elrayah ; Singule, Vladislav (referee) ; Skala, Bohumil (referee) ; Skalický, Jiří (advisor)
Je jasné, že nejúspěšnější konstrukce zahrnuje postup vícefázového řízení, ve kterém každá fáze může být považována za samostatný modul. Provoz kterékoliv z jednotek musí mít minimální vliv na ostatní, a to tak, že v případě selhání jedné jednotky ostatní mohou být v provozu neovlivněny. Modulární řešení vyžaduje minimální elektrické, magnetické a tepelné ovlivnění mezi fázemi řízení (měniče). Synchronní stroje s pulzním tokem a permanentními magnety se jeví jako atraktivní typ stroje, jejíž přednostmi jsou vysoký kroutící moment, jednoduchá a robustní konstrukce rotoru a skutečnost, že permanentní magnety i cívky jsou umístěny společně na statoru. FS-PMSM jsou poměrně nové typy střídavého stroje stator-permanentní magnet, které představují významné přednosti na rozdíl od konvenčních rotorů - velký kroutící moment, vysoký točivý moment, v podstatě sinusové zpětné EMF křivky, zároveň kompaktní a robustní konstrukce díky umístění magnetů a vinutí kotvy na statoru. Srovnání výsledků mezi FS-PMSM a klasickými motory na povrchu upevněnými PM (SPM) se stejnými parametry ukazuje, že FS-PMSM vykazuje větší vzduchové mezery hustoty toku, vyšší točivý moment na ztráty v mědi, ale také vyšší pulzaci díky reluktančnímu momentu. Pro stroje buzené permanentními magnety se jedná o tradiční rozpor mezi požadavkem na vysoký kroutící moment pod základní rychlostí (oblast konstantního momentu) a provozem nad základní rychlostí (oblast konstantního výkonu), zejména pro aplikace v hybridních vozidlech. Je předložena nová topologie synchronního stroje s permanentními magnety a spínaným tokem odolného proti poruchám, která je schopná provozu během vinutí naprázdno a zkratovaného vinutí i poruchách měniče. Schéma je založeno na dvojitě vinutém motoru napájeném ze dvou oddělených vektorově řízených napěťových zdrojů. Vinutí jsou uspořádána takovým způsobem, aby tvořila dvě nezávislé a oddělené sady. Simulace a experimentální výzkum zpřesní výkon během obou scénářů jak za normálního provozu, tak za poruch včetně zkratových závad a ukáží robustnost pohonu za těchto podmínek. Tato práce byla publikována v deseti konferenčních příspěvcích, dvou časopisech a knižní kapitole, kde byly představeny jak topologie pohonu a aplikovaná řídící schémata, tak analýzy jeho schopnosti odolávat poruchám.
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Motor-Generator For Swirl Turbine
Huzlík, Rostislav ; Skala, Bohumil (referee) ; Duroň, Jiří (referee) ; Ondrůšek, Čestmír (advisor)
The aim of this doctoral thesis is to design a motor-generator for swirl turbine. Swirl turbine is a relatively new type of turbine developed at the Department of Fluid Engineering Viktor Kaplan Energy Institute FME BUT. Swirl turbine is designed for use on small head, where the classical types of turbines either poor efficacy or are economically disadvantaged. As suitable construction for the motor-generator was selected synchronous machine with permanent magnets and with axial magnetic flow with coreless stator. As part of the work is carried out calculating the properties of turbines for defined operating point simulation model of the turbine. After already made draft motor-generator to optimally meet the characteristics of the turbine. The complete design of the motor-generator is validated by calculating the finite element method models. Designed machine must be able to work as a generator and as a motor, if it was necessary to use a turbine as a pump.
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Standard of general laic public knowledge of first aid giving
Nechanická, Veronika ; Slowik, Regina (advisor) ; Skála, Bohumil (referee) ; Býma, Svatopluk (referee)
The synopsis of principles of first aid, including the newest guidelines for cardiopulmocerebral resuscitation was elaborated in this work. The selected states altering the human health or life-threatening conditions were mentioned, including their recommended management. The recommendations for appropriate calling for an ambulance were elaborated and the remark concerning criminal law was made. In the practical part of this work the answers of 99 respondents to questions investigating the basic sociometric and demografic data and elementary knowledge of first aid were analyzed. The hypotheses that people who had undergone first aid training, who had dealt with the accident or emergency in real life, and people with medical education have better knowledge of first aid were confirmed. The people who evaluated their own knowledge of first aid as good from their subjective point of view really had better knowledge. The hypothesis of direct proportion between knowledge of first aid and achieved education was confirmed in the female group. The assumption that the youngest and the oldest generation has the worst knowledge of first aid was also confirmed. The surprising findings were revealed in the male group. A group of the youngest respondents and a group with the lowest education had the best...
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Health support by a nurse in the primary care
Podracká, Simona ; Skála, Bohumil (advisor) ; Vosečková, Alena (referee) ; Pekárková, Hana (referee)
The baccalaureate work is dealing with health support in the primary care, in particular with the activity of a nurse, and how the nurse can actively contribute to the improvement of the health level of the population. It evaluates, in which part of prevention and care the nurse should be more active, and which questions she is to target first. As a method there is used an interview of a selected group of respondents. The interview should reveal the level of knowledge in the field of alimentation, sporting activity and health care and support. The men - blood donors of age between 40 and 50 in the Transfusion Department of the Teaching Hospital in Hradec Králové were addressed. The output of the inquiry was put under analysis with the object to target the knowledge deficiencies. The results can be instrumental for the educational activity of the nurse in the primary care.
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The mistakes of non-professional during the first aid intervention
Sábová, Petra ; Kykal, Jan (advisor) ; Kupečková, Ivana (referee) ; Skála, Bohumil (referee)
Bachelor's survey about providing of first aid intervention and the relevant mistakes, which are done by non-professionals. It guides how to correctly process the first aid intervention. The survey describes the principles of automated external defibrillators, telephonic assist basic life support, touches the law and connected sanctions when the first aid is refused. The study brings proposal to include the theme of first aid in to curriculum the core of the study makes quantitative survey of first aid assistance training, refuses of first aid, misuse of first aid and guidelines how to assist. The samples are ordinary people and professional, as well.
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Losses Analysis in Electric Machines under Special Conditions
Bulín, Tomáš ; Rafajdus, Pavol (referee) ; Skala, Bohumil (referee) ; Ondrůšek, Čestmír (advisor)
This thesis deals with the analysis of magnetic losses in electrical machines and the possibilities of their measurement. Magnetically soft and hard materials are very prone to changing magnetic properties. They can be changed simply by changing the temperature of the material or different stresses induced in the material, resulting in different results. These changes are important to keep in mind when an electric machine is being designed. The original parameters of the affected materials can be restored by annealing or grinding. These methods release the induced stresses within the material. Due to these effects, it is also important to know how to measure magnetic parameters. Each way has its own specifics and has a certain error of the measurement. When the machines for higher efficiency, rpm or higher temperatures are designed, it is advisable to know how their magnetic properties changed. This thesis deals with the properties of different materials, their measurements and finally simulation of the chosen electric machine with the application of the measured results.
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Public participation in preventive examinations
Kroužilová, Monika ; Svobodová, Dita (advisor) ; Konštacký, Stanislav (referee) ; Skála, Bohumil (referee)
Author: Kroužilová Monika Institution: Institute of Social Medicine LF UK in Hradec Králové, Departement of Nursing Title of work: Public participation in preventive examinations Supervisor: Mgr. Svobodová Dita Number of pages: 92 Number of attachments: 2 Year of the defence: 2011 Keywords: Health, Lifestyle, Preventive examinations, Cancer prevention, Screening Bachelor's thesis is about participation of public on preventive medical examinations and trying to map knowledge and concerns of public about given theme. Theoretical part is divided to three chapters. In first chapter is author describing used nomenclature, health determinants, impact of lifestyle. In second chapter is analyzed status of preventive examinations in medical care, third chapter is aimed for oncology prevention. Practical part represents quantitative research, for which method of questionnaires was used. Examined sample contains 30 women and 30 mens. Gathered informations are presented using graphical illustrations, sometimes including graphs by demographical values. Goal of thesis was to find out, how well is public informed about preventive examination options and if is public interested in them at all.
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Health related quality of life in adult patients with chronic obstructive pulmonary disease (COPD)
Klikarová, Dita ; Prchalová, Eva (advisor) ; Borkovcová, Jitka (referee) ; Skála, Bohumil (referee)
Bachelor these is ranged on the quality of life of patiens with chronic obstruktive pulmonary disease. Theoretical part deals about quality of life itself and simultaneously about disease problems COPD. It deals with its definition, prevalence, symptome, prognosis, prevention, diagnostics, therapy and even possible developped complikations , which this disease could bring. The purpase of empiric part seems to be discovery of subjective quality of life of patiens with COPD. Eack patient feels his disease absolutely individually. Inportant search was realized at quantitative and qualitative research.
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