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Rotor fault diagnosis of induction motors
Bednařík, Václav ; Cipín, Radoslav (referee) ; Vítek, Ondřej (advisor)
This bachelor thesis focus on the faults of induction motors. In general terms to mechanical and electirc faults and their influence on induction motor. Further on the tests, that are conducted on induction motors to detect faults and states that precede them. Main part is devoted to rotor eccentricity and broken rotor bars. Eccentricity is solved within theoretical analysis and measurements on free damaged motors. As well as broken rotor bars, which are supplemented by measurements on three damaged rotors. There are two types of eccentricity, static and dynamic. Faults of broken rotor bars is solved in terms of postion of broken rotor bars and their number.
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Complex Analysis of Modal Properties of Rotating Electrical Machines
Donát, Martin ; Vlach, Radek (referee) ; Žiaran,, Stanislav (referee) ; Dušek, Daniel (advisor)
This dissertation thesis deals with the computational modelling of the dynamic response of the rotating electrical machine structure on the application of the magnetic forces. Apart from the dynamic response of the ideal symmetrical machine, the influence of the air gap eccentricity on the dynamics response is studied in this work. A basic type of the air gap eccentricity, which is caused by eccentric mounting of the rotor pack on the shaft of the rotor, is considered. The calculations the dependence of the magnetic forces on the time and a misalignment of the rotor pack are performed as first. The computational model of the magnetic field of the rotating electrical machine, which is based on solution of the electromagnetic coupled field analysis by finite element method, is used for this purpose. An analysis of the influence of the unbalanced magnetic pull and the stiffness of some parts of the machine on the modal properties of the machine is performed in the second part of this thesis. A third part of this thesis is focused on the calculation of the dynamic response of the machine during the steady state operation of the machine and the influence of the rotor pack misalignment on the dynamic response is studied. The obtained results showed that the tangential components of the magnetic forces, which act on the stator pack, excite significant torsional vibration of the stator. Besides the vibration of the stator of the machine, the influence of the rotor pack misalignment on the sound power of the machine, vibration of the rotor, loads of rotor bearings and air gap eccentricity is studied in this thesis.
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Design of computational algorithm of electric machine rotor with respect to stress-strain relationships and critical speed
Pařízek, Daniel ; Lošák, Petr (referee) ; Vlach, Radek (advisor)
The Master's thesis deals with the mechanical design of electric machine rotor. Within the first two chapters of the practical part of the thesis two simplified computational models of the rotor (level 1 models) are compiled. Specifically, the model of flexible rotor mounted on rigid supports and model of rigid rotor mounted on flexible supports. The essence of these computational models lies in solvability using simple equations. Using these models can save time when constructing a pre-design of the rotor geometry. The following chapter is devoted to comparing different approaches to computational modeling of rotor using FEM. A predetermined preliminary design of a high-speed massive rotor is investigated. Computational models of different levels at stress-strain analysis and modal analysis are presented. It also includes a suggestion on how to proceed effectively in a given analysis.
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Design of computational algorithm of electric machine rotor with respect to stress-strain relationships and critical speed
Pařízek, Daniel ; Lošák, Petr (referee) ; Vlach, Radek (advisor)
The Master's thesis deals with the mechanical design of electric machine rotor. Within the first two chapters of the practical part of the thesis two simplified computational models of the rotor (level 1 models) are compiled. Specifically, the model of flexible rotor mounted on rigid supports and model of rigid rotor mounted on flexible supports. The essence of these computational models lies in solvability using simple equations. Using these models can save time when constructing a pre-design of the rotor geometry. The following chapter is devoted to comparing different approaches to computational modeling of rotor using FEM. A predetermined preliminary design of a high-speed massive rotor is investigated. Computational models of different levels at stress-strain analysis and modal analysis are presented. It also includes a suggestion on how to proceed effectively in a given analysis.
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Rotor fault diagnosis of induction motors
Bednařík, Václav ; Cipín, Radoslav (referee) ; Vítek, Ondřej (advisor)
This bachelor thesis focus on the faults of induction motors. In general terms to mechanical and electirc faults and their influence on induction motor. Further on the tests, that are conducted on induction motors to detect faults and states that precede them. Main part is devoted to rotor eccentricity and broken rotor bars. Eccentricity is solved within theoretical analysis and measurements on free damaged motors. As well as broken rotor bars, which are supplemented by measurements on three damaged rotors. There are two types of eccentricity, static and dynamic. Faults of broken rotor bars is solved in terms of postion of broken rotor bars and their number.
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Complex Analysis of Modal Properties of Rotating Electrical Machines
Donát, Martin ; Vlach, Radek (referee) ; Žiaran,, Stanislav (referee) ; Dušek, Daniel (advisor)
This dissertation thesis deals with the computational modelling of the dynamic response of the rotating electrical machine structure on the application of the magnetic forces. Apart from the dynamic response of the ideal symmetrical machine, the influence of the air gap eccentricity on the dynamics response is studied in this work. A basic type of the air gap eccentricity, which is caused by eccentric mounting of the rotor pack on the shaft of the rotor, is considered. The calculations the dependence of the magnetic forces on the time and a misalignment of the rotor pack are performed as first. The computational model of the magnetic field of the rotating electrical machine, which is based on solution of the electromagnetic coupled field analysis by finite element method, is used for this purpose. An analysis of the influence of the unbalanced magnetic pull and the stiffness of some parts of the machine on the modal properties of the machine is performed in the second part of this thesis. A third part of this thesis is focused on the calculation of the dynamic response of the machine during the steady state operation of the machine and the influence of the rotor pack misalignment on the dynamic response is studied. The obtained results showed that the tangential components of the magnetic forces, which act on the stator pack, excite significant torsional vibration of the stator. Besides the vibration of the stator of the machine, the influence of the rotor pack misalignment on the sound power of the machine, vibration of the rotor, loads of rotor bearings and air gap eccentricity is studied in this thesis.
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Complex analysis of modal properties of rotating electrical machines
Donát, Martin ; Dušek, Daniel (advisor)
This dissertation thesis deals with the computational modelling of the dynamic response of the rotating electrical machine structure on the application of the magnetic forces. Apart from the dynamic response of the ideal symmetrical machine, the influence of the air gap eccentricity on the dynamics response is studied in this work. A basic type of the air gap eccentricity, which is caused by eccentric mounting of the rotor pack on the shaft of the rotor, is considered. The calculations the dependence of the magnetic forces on the time and a misalignment of the rotor pack are performed as first. The computational model of the magnetic field of the rotating electrical machine, which is based on solution of the electromagnetic coupled field analysis by finite element method, is used for this purpose. An analysis of the influence of the unbalanced magnetic pull and the stiffness of some parts of the machine on the modal properties of the machine is performed in the second part of this thesis. A third part of this thesis is focused on the calculation of the dynamic response of the machine during the steady state operation of the machine and the influence of the rotor pack misalignment on the dynamic response is studied. The obtained results showed that the tangential components of the magnetic forces, which act on the stator pack, excite significant torsional vibration of the stator. Besides the vibration of the stator of the machine, the influence of the rotor pack misalignment on the sound power of the machine, vibration of the rotor, loads of rotor bearings and air gap eccentricity is studied in this thesis.
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