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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.
341

Alternativní zdroj elektrické energie na železniční trati / Energy harvesting generator for train track side

Pribulla, Daniel January 2018 (has links)
Cieľom tejto práce bolo navrhnúť alternatívny zdroj energie pre riadiacu jednotku, ktorú obsahujú komponenty traťového zabezpečovacieho zariadenia v rámci európskeho systému riadenia železničnej dopravy. V porovnaní s predchádzajúcimi harvestormi bola vďaka použitiu lineárneho elektrického generátora eliminovaná mechanická väzba, ako napr. prevodovka. To by malo zvýšiť životnosť a spoľahlivosť zariadenia. S pomocou analógie magnetických obvodov a softvéru využívajúceho metódu konečných prvkov FEMM a Ansys Maxwell, boli navrhnuté tri rôzne synchrónne generátory s permanentnými magnetmi. Simulácia v prostredí Matlab Simulink dokázala, že výsledný návrh generátora je schopný dodávať priemerný výkon 5 W počas prechodu vlaku zo stlačenia pražca väčšieho ako 2 mm.
342

Elektronicky komutovaný motor / The electronic commutation motor

Bláha, Martin January 2008 (has links)
This work discusses about nowadays problematic of the electronic comutation motors.This work also describes the opportunity of electronic control of these motors. The result of this work is realization of electronic control circuit from discreet components. There also are mentioned is proposal of electronic control board from SMD components. This control board include temperature control with ventilator switching , commutation logic, PWM speed control. In the last part of this paper are results of evaluation measurements of EC motor.
343

Řízení stroje s PM v d-q osách při použití Matlab/Simulink / Control of salient PM machine using d-q frame machine model and Matlab Simulink

Dušek, Jiří January 2010 (has links)
Tato práce se zabývá synchronním motorem s permanentními magnety na rotoru (PMSM), jeho modelováním a návrhu regulační struktury. V práci jsou uvedeny způsoby a výhody použití permanentních magnetů v elektrických motorech. Dále se práce zabývá transformací třífázové soustavy do dq0. Pomocí Parkovy transformace jsou v práci odvozeny rovnice stroje v dq0 souřadnicovém systému a vytvořeny náhradní schémata stroje v dq osách. Rovnice i schémata zahrnují jak ztráty v mědi, tak ztráty v železe. Náhradní schémata jsou popsány elektrickými a mechanickými rovnicemi a následně překresleny do grafické podoby v programu Matlab Simulink. Vytvořeny jsou dva modely PMSM, jeden s uvažováním ztrát v železe a druhý bez těchto ztrát. Pro oba dva modely je zde popsán postup návrhu regulátorů proudu a otáček. Pro model, u kterého jsou uvažovány ztráty v železe je navíc použito více druhů řídicích strategií a tyto strategie jsou mezi sebou navzájem porovnány.
344

Analýza a inovace elektrických motorků pro automobily / Automotive Electric Motors Analysis and Innovation

Špaček, Ladislav January 2011 (has links)
Direct current motors and stepping motors are very often used for electric drives in cars. The most frequent representatives of direct current motors are electric starter and wind- screen wiper motor. Stepping motors are very often used for electric regulating of outsides driving mirrors and seats. This study is focused on innovation and DC permanent magnet motor. The disadvanage of direct current motors is so called „sliding contact“. A possible compensation of direct current motor are EC (electronically commutator) motors that do not need sliding contact for their work.
345

Řešení rozložení magnetického pole ve stejnosměrném stroji / Solution magnetic field distribution in DC machine

Hájek, Jan January 2012 (has links)
This thesis deals with distribution of magnetic fields in the DC machine. Part of this thesis is the introduction of DC machines, principles of operation and distribution of DC machines. There is also discussed electrically commutated motors. The thesis demonstrates the types of permanent magnets and their properties. Then there is an analysis of the magnetic field electrically commutated motor Atas Nachod in the Ansoft Maxwell. Using Ansoft Simplorer, switching is carried out of the engine. Another part of this work is the analysisthe magnetic field electrically commutated motor Atas Nachod for three types of slot of the stator of the engine. Here it is seen what impact the change has slot on the distribution of magnetic field in the EC motor. Finally, training is carried out measurements of electrically commutated motor BOYANG BY92BL48-4000-2200.
346

Analýza a inovace elektrických motorků pro automobily / Automotive Electric Motors Analysis and Innovation

Vala, Tomáš January 2012 (has links)
Electric drives used in automotive industry are often based on standard DC motor as it is widely recognised as mature and reliable technology. The most common applications of DC motors in automotive industry are starters and wind screen wiper motors. Aim of this thesis is to provide design overview of typical automotive DC motor therefore main parts and features of the machine will be described in detail. Main disadvantage of DC motor is „sliding contact“ between commutator and carbon brushes which introduces source of electromagnetic disturbance and requires regular maintenance. Within this project different aspects of DC motor design and innovation are expected to be tackled including examples of loss calculation.
347

Laboratorní soustrojí s asynchronním a stejnosměrným motorem / Laboratory machine-set with induction and DC machine

Hudák, Ondřej January 2012 (has links)
The work addresses the design and implementation of a universal laboratory workstation designed to teach a course on electrical drives. Workplace will be formed sets consisting of DC motor with permanent magnet on a 400W power supply voltage of 24V and induction motor with 180W power on 3x24V. The engines are connected through a flexible shaft coupling. The asynchronous motor is located on the extended shaft resolver for scanning speed and rotor position. Both engines will be supplied from the transistor inverters. The workplace will be designed for maximum clearness and resistance to damage by improper handling.
348

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.
349

Elektromagnetický tlumič / Electromagnetic damper

Mikyska, Jan January 2014 (has links)
This master´s thesis is focused on obtaining electrical energy from vibration control car using electromagnetic dampers. The primary use of the electromagnetic damper is the production of electrical energy, which can then be used to power electrical appliances in your car or battery charging. The thesis is divided into six main parts: a literature review of possible ways of getting electricity from the car damping, theoretical and mathematical analysis of problems, the choice of design with computational analysis of dampers and power calculation.
350

Návrh a analýza synchronních strojů s permanentními magnety / Design and analysis of permanent magnet synchronous machines

Blaha, Jan January 2015 (has links)
Characteristics of synchronous machines with permanent magnets depend among others on geometric layout of the machine section. Unlike EC motors, where rectangular arrangement of quantities is suitable, these machines require sinusoidal behaviour. Specific forming of individual machine parts is partially derived from this requirement. This thesis deals with design of such machines, including various geometrical modifications of their sections and examination of influence of those modifications. The thesis includes also analytical calculation procedure of machine parameters as well as verification of final characteristics using the finite element method. It results in a combination of various design methods. FEMM, Maxwell RMxprt and Maxwell 2D Transient Analysis programs were used for verification. Individual modifications of machine geometries are applied to machines with concentrated windings with different ratio of number of slots and poles, and differences between machines and results of individual methods are compared.

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