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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Vlivy výrobních tolerancí permanentních magnetů na synchronní motory s permanentními magnety / Effect of Manufacturing Variations of Permanent Magnets in Surface-Mounted Permanent Magnet Motors

Vícha, Adam January 2016 (has links)
Master’s thesis summs up issues of mounting pemanent magnets on rotor surface of permanent magnet synchronous machine. Literature reseach is divided in two parts. First one shows studies and experiments researching the impact of manufacturing tolerances of permanent magnets and wrong mounting on the rotor on cogging torque . The second part focus on analytical aproach of defining influence of permanent magnets on magnetic flux density in the air gap and phase induced voltage. Practical part focus on design of a prototype machine, wich will be used to research the impact of tolerances and imperfections. Parametric model of the prototype machine is created in Maxwell and is subjected to analysis via finite element method. Three different analysis were run, offset of permanent magnet, decrease and wrong dicertion of magnetization. At last the result of cogging torque and induced voltage are compared.
12

Moderní metody bezsnímačového řízení pohonů s PMSM motorem / Novel Methods of Sensorless Control of Drives with PMSM Motor

Lepka, Jaroslav January 2018 (has links)
Purpose of this dissertation is to explore control techniques of PMSM motors and the design of a complex solution of sensorless control across a wide range of speed and torque. The proposed solution supports industrial implementation of different types of end equipment which use a PMSM motor. The work covers a thorough analysis of position and speed estimation. The Control structure is based on field oriented control technique, processes estimated quantities, and optimizes motor conditions to achieve maximum efficiency, start-up torque, and speed. The work discusses how the solution complies with the latest IEC standards. Compliance with these standards requires adapting the sensorless control technique and field oriented control structure. The elimination of a rotor position sensor and a temperature sensor measuring winding temperature requires development of techniques in software for blocked rotor detection and overload detection. The proposed solutions, which have been granted US patents, are explained in this work and utilize the unique features of an NXP microcontroller optimized for motor control applications. The achieved results are demonstrated on real industrial applications.
13

Návrh vysokootáčkového asynchronního motoru / Design of high speed induction motor

Čech, Jiří January 2020 (has links)
The first part of this paper presents general information about electromagnetic designing of an induction motor. Focus is on explanation of individual designing aspects and their effects on final motor parametres. Design principles for magnetic cores, slot dimensioning, stator winding and rotor squirrel cage are presented. Second chapter presents complete analytical computation of a given induction motor. Firstly several parametres need to be selected. Then sizing of stator and rotor is conducted. Secondly steady state equivalent parametres and related operating characteristics are computed. Following chapter consinsts of three final designs. In the last chapter results of mechanical analysis are presented.
14

Bezsnímačové řízení střídavých motorů na platformě STM32 / Sensorless control of AC motors on STM32 platform

Soviš, Jiří January 2021 (has links)
The thesis is focused on the issue of sensorless vector control of a synchronous motor with permanent magnets in the low-speed range. In the first part, there is a brief description of the synchronous motor and the necessary transformations for the application of vector control. This is followed by the overview of sensorless methods for position estimation by injecting a high-frequency harmonic signal. The practical part is devoted to the implementation of a control algorithm to develop kit STM32NUCLEO-L476RG, which is preceded by the identification of all engine parameters. As part of the implementation, a structure including current, speed and position control was designed. The functionality and robustness of the settings have been successfully tested due to the different inertia and load.
15

Identifikace parametrů asynchronního motoru / Identification of AC induction motor parameters

Křížek, Tomáš January 2008 (has links)
This thesis describes and realizes (in program Matlab/Simulink and in the microcontroller Freescale 56F8346) one off-line identification method of AC Induction motor parameters which are necessary to implement the field-oriented control strategy. The identification metod identify leakage inductance, magnetizing inductance and secondary time constants. The presented method is evaluted, advantages and disadvantages of this method are evaluated with reference to their possible use in real-machine. The experimental results and schemes which are presented demonstrate the feasibility methods. The thesis is dividend in seven chapters. Second chapter describes the basic principle and model AC induction motor. Third chapter generally describes identification methods. Fourth, fifth and sixth chapters deal with method which is based on a previous work of the authors [4] and [5].
16

Simulace pohonu hybridního automobilu / Simulation of hybrid car drive

Byrtus, Jiří January 2013 (has links)
This thesis deals with analysis of electric drive parts from hybrid electric vehicle, namely interior permanent magnet synchronous motor and inverter with control. First part describes a basic theory. Further, motor and inverter computer models are shown, specified simulations are performed on this models. Results are compared with values measured on real machines from accessible literary sources.
17

Řídicí jednotka pro BLDC motor / Control unit for BLDC motor

Krejčí, Ondřej January 2014 (has links)
This master„s thesis elaborates with EC motors problematic. There are described essential features of brushless DC motors, their principles, construction and methods for rotor position detection. There are mentioned commonly used control algorithms of EC motors including theory of three-phase convertors. This thesis also contains a complex design of the universal convertor for EC motor and its practical implementation. Power parts losses calculation, heat-sink calculation and measurements at the convertor prototype are also described in this thesis.
18

Zvyšování účinnosti třífázových asynchronních motorů / The improvement of efficiency of three-phase induction motors

Vinkler, Stanislav January 2014 (has links)
This work is dedicated to increasing the effectiveness of a particular draft induction motor, which was before the change and subjected to laboratory measurements according to EN60034 - 2-1, an analytical calculation of the losses and the overall efficiency and analysis program RMxprt. The first part focuses on the analysis of measurement data, measurement of partial loss in the machine and overall efficiency. In the second chapter, losses and efficiency calculated analytically, in the first case using the links in the professional literature dealing with the design of electric motors and in the second case by a program for the rapid design of rotating electrical machines, RMxprt program. At the end of this chapter all parameters are obtained measurements and calculations are compared. The third chapter is devoted to the calculation of losses and the resulting efficiency machines in a computer program, in which I gradually adopted changes to increase the efficiency of electrical machines. It also shows the calculation of the new dimensions of the stator and rotor slots. In the fourth chapter, the preparation of documentation for the production of a new two-layer winding for the current machine, while preserving the original dimensions of stator slots. The last part is devoted to the analysis of measurement data on the supplied asynchronous motor with a newly designed stator winding. In conclusion then discussed the results of work.
19

Energetické parametry jednofázových asynchronních motorů / Energy parameters of single-phase induction machines

Janáček, Martin January 2016 (has links)
The master's thesis deals and introduces a single-phase inductions machines, the principle of operation, types of design and operating conditions. This thesis includes analysis of individual losses in the machine and reduce the possibility of different ways. After a theoretical proposal for reducing losses are measured by mass-produced single-phase induction machine. Further machine modifications proposed for reducing losses in the stator windings and designed a prototype machine with the adjustment of the magnetic circuit to reduce iron losses made by ATAS elektromotory Nachod a.s. The results are supplemented by a simulation using software Maxwell RMxprt and finite element method (FEM). Finally, they are compared to each machines modifications mainly in terms of energy consumption.
20

Динамички модел трофазне кавезне асинхроне машине заснован на методи коначних елемената / Dinamički model trofazne kavezne asinhrone mašine zasnovan na metodi konačnih elemenata / Dynamic model of three-phase squirrel-cage induction machine based onfinite elements method

Jerkan Dejan 08 December 2016 (has links)
<p>Тема докторске дисертације је развој и верификација новог динамичког<br />модела трофазне кавезне асинхроне машине, који је заснован на<br />методи коначних елемената. Применом линеарних магнетостатичких<br />симулација и time-harmonic нелинеарних симулација се реконструишу<br />индуктивности динамичког модела машине заснованог на вишеструко<br />спрегнутим електричним колима. Модел се затим користи у<br />истраживању феномена везаних за појаву жљебних хармоника,<br />сатурацијом индукованих хармоника, као и у развоју нове методе<br />детекције сломљних шипки у роторском кавезу.</p> / <p>Tema doktorske disertacije je razvoj i verifikacija novog dinamičkog<br />modela trofazne kavezne asinhrone mašine, koji je zasnovan na<br />metodi konačnih elemenata. Primenom linearnih magnetostatičkih<br />simulacija i time-harmonic nelinearnih simulacija se rekonstruišu<br />induktivnosti dinamičkog modela mašine zasnovanog na višestruko<br />spregnutim električnim kolima. Model se zatim koristi u<br />istraživanju fenomena vezanih za pojavu žljebnih harmonika,<br />saturacijom indukovanih harmonika, kao i u razvoju nove metode<br />detekcije slomljnih šipki u rotorskom kavezu.</p> / <p>Topic of this thesis is development and verification of the novel dynamical<br />model of the three phase squirrel-cage induction machine, which is based on<br />the finite elements method. Linear magnetostatic simulations and nonlinear<br />time-harmonic simulations are used for calculation of the inductances of the<br />dynamic model of the machine based on the moultiple coupled circuit<br />approach. Model is then used for investigation of the rotor slot harmonics,<br />saturation induced harmonics and in the development of the novel method<br />for broken rotor bars detection.</p>

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