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Study of concentrated winding induction motor
Trn, Ondřej ; Ondrůšek, Čestmír (referee) ; Vítek, Ondřej (advisor)
This diploma thesis deals with the possibility of using a concentrated winding in an induction motor and the use of copper bars in a rotor cage. The first part of the thesis explains the basic theoretical knowledge of the operation and principle of the induction machine. In this theoretical part we will learn what is actually a concentrated winding and how it is placed on the stator. The second part is focused on the analytical design of the machine with classical distributed winding and with concentrated winding. The third theoretical part is an introduction to the issue of influencing the motor harmonics. The last final part of the thesis shows differences in operational properties of designed machines.
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Proposal of Communication Mix of the Selected Company
Boček, Petr ; Vítek, Ondřej (referee) ; Milichovský, František (advisor)
The thesis is a proposal of communication mix for selected company. The chosen company is Pantograff art store, which sells paints in spray and paints. The diploma work is divided into 3parts. The first part is theoretical, where the theoretical background of the given topic of marketing research on the B2C market is described. The analytical part focuses on important analyzes for the revitalization of the existing communication mix of the company. In the last part of the thesis there are individual suggestions for improving the marketing of the company.
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Design of a Magnetic Bearing for an Electrical Machine
Rúra, Dávid ; Vítek, Ondřej (referee) ; Bárta, Jan (advisor)
The current development in the field of electric machinery is focusing on high-speed electric machines. This opens also other fields related to high-speed machines. One of them are magnetic bearing systems. Tradition approach of using ball bearing brings a few problems in design dealing with friction at high speeds. Together with magnetic bearings, development is their control. Faster chips opened a new way of thinking of control and helped to evolve robust control loops. The biggest advantage of magnetic bearing is non-friction run and almost no maintenance. Compare to traditional ball bearing, a magnetic bearing system needs more space and in some applications could happen that the shaft will be twice as long. This problem can be solved designing complex system with motor and integrated magnetic bearing what leads to downsizing. In this master thesis, the design of magnetic bearing for 12kw, 45000rpm is discussed. It focuses on practical design and correlations between parameter selection. The analytical approach is used to sketch the design and optimization is done afterwards. Problem with an analytical design is that it doesn't cover all parasitic phenomenae and thus numerical modelling snd optimization are demanded. Also, the critical speed analyze is included in this thesis. The results of the work will be used for manufacturing prototype as an extension to the existing high-speed machine.
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Design of interior permanent magnet synchronous motor
Žák, Ondřej ; Mach, Martin (referee) ; Vítek, Ondřej (advisor)
The thesis describes problematics of synchronous motor with permanent magnets. The design is provided by analytic and empiric procedures. The great accent is placed on the description of the magnetic circuit of the motor. The finite element method analysis of designed motor is performed subsequently. The main target of this thesis is to find the way, how the ferrite permanent magnet should be used in synchronous motor.
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FEM Analysis of a Hybrid Synchronous Generator
Suchomel, Vít ; Ondrůšek, Čestmír (referee) ; Vítek, Ondřej (advisor)
This work deals with calculation and design of synchronous salient pole generator and then the transformation from this machine into so-called hybrid synchronous machine is described. This diploma thesis is done for company Siemens Electric Machines s.r.o. in Drásov. This company provided their design of synchronous salient pole generator. The model of this generator was created in programs RMxprt and Maxwell 2D. Suggestions and models were compared, and their calculated parameters were evaluated. The created model was upgraded to so-called hybrid synchronous generator. Permanent magnets were added in the created model and influence of these additional magnets is going to be analyzed. Tasks of the work are described in more details. in the introduction. The topic of synchronous generator and hybrid synchronous generator in general is described in the theoretical part. The next part of work deals with the design of salient pole generator. In the other part of the work calculation and design of the generator model are described in Ansys program. Furthermore there are some results from program compared with the results from company. Some model parts and other graphic outputs from Ansys program are shown. After that the creation of hybrid synchronous generator is described and created models of hybrid synchronous generators are compared and evaluated.
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Optimization of magnetic circuit of induction motor for frequency up to 210 Hz
Binek, Martin ; Cipín, Radoslav (referee) ; Vítek, Ondřej (advisor)
This master’s thesis first deals with the theory concerning induction motor. It briefly desbribes the construction of three-phase induction motors, the generation of tractive force, power flow with loss distribution and also torque characteristic. In the next part an analytical calculation of the parameters of equivalent circuit for an existing induction motor with known dimensions is performed. After the calculation it is possible to find out the rated parameters of the motor, which makes it possible to further compare results with the values obtained by other methods. The next step was to create a model of the motor in RMxprt program, which is later also translated to ANSYS Maxwell 2D model. Simulations were carried out in both interfaces. As the next step the results obtained by the three methods are compared with measured values and also evaluated. The final part of the thesis focuses on the optimization of the magnetic circuit for higher frequencies. Efficiency of the modified induction motor is examined for higher frequencies using RMxprt Optimetrics and this procedure is performed for both default and alternative electrical steel materials.
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Measurement and simulation of synchronous reluctance machines
Gábriš, Richard ; Bárta, Jan (referee) ; Vítek, Ondřej (advisor)
This semester thesis describes the principle of operation and a usage of synchronous reluctance motors. The core of the thesis is devided into two parts. The first one is a description of a measurement of motor samples and evaluation of the measurement. Subject matter of the second one is designing of motor models in application ANSYS Maxwell, analysis of the results and their comparison with the results obtained by the measurement.
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Efficiency improvement of single-phase induction motor
Bořil, Michal ; Mach, Martin (referee) ; Vítek, Ondřej (advisor)
The subject-matter of the Bachelor Thesis is increasing efficiency of a single-phase asynchronous motor. The thesis is divided into several parts and comprises information concerning the subject-matter. The first part deals with the theoretical principle of all rotary machines from three-phase motors to single-phase motors, describing the principle, design and functionality of these devices in detail. In the second part, a new motor model is designed on the basis of the label values of a specified asynchronous motor and adapted to have the highest possible efficiency. The model of the motor is created in the ANSYS RMxprt program and compared to a model of the specified motor, which is also created on the basis of parameters of the technical documentation in the same program. In the last but one part of the Bachelor Theses, several models are created with proposed modifications of the motor to increase efficiency and compared to the specified motor. This part focuses on an analysis of individual types of losses that influence the efficiency and power of the motor. In the last part of the Bachelor Thesis, in the ANSYS Maxwell program, a model of the specified motor and a model of the motor with the highest efficiency is simulated with the use of FEMM. The obtained information of the models from the Maxwell program is compared to information obtained from the RMxprt program and evaluated.
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FEM model and simulation of induction motor with pole-changing winding
Záškodný, Jiří ; Ondrůšek, Čestmír (referee) ; Vítek, Ondřej (advisor)
This master thesis deals with calculations and simulations of multi-speed induction motors. In the first part, basic principle of these machines is described. Next, there are given three examples of pole-changing stator windings and their properties are analyzed (winding factors, magnetomotive force). Main part includes simulations and measuring of the specific motor, which is produced by company Siemens Mohelnice. This is the motor with 2/1 pole-changing in Y/YY connection. First, influence of skewed rotor slots on current and torque is analyzed. Next, parametres of motor from simulations are given and these results are compared to measured values.
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Contactless loading and measurement of high-speed machines
Vojče, Zbyněk ; Ondrůšek, Čestmír (referee) ; Vítek, Ondřej (advisor)
Práce se zabývá problematikou měření momentu u velmi vysokootáčkových strojů. Z důvodů vysokých rychlostí jsou tradiční metody měření momentu nepoužitelné, z tohoto důvodu je nutno vyvinout novou bezkontaktní metodu. Pro měření je zvolena metoda zatěžování vířivou brzdou, pro kterou je proveden analytický výpočet jejích vlastností pomocí Maxwellových rovnic a je vytvořen model vířivé brzdy v programu FEMM a Ansys/Maxwell 2D. Na závěr jsou výsledky simulací a výpočtů porovnány s měřením na prototypech brzdy.
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