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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

Řízení BLDC motoru v oblasti nízkých otáček / Control algorithms for BLDC motor for low speeds

Kozáček, Peter January 2015 (has links)
The diploma work concerns on an issue of data collection of speed and electrical angle based on informations from Hall sensor with the necessary resolution for control of BLDC motor. Specifically, concenred on a section with low speed. Most of moors use Hall sensor for detecting speed and position of the rotor. At low speed section, becomes the situation when we can not determine the position of the rotor with (the) required (sufficient) resolution, this situation creates a „wince“ in the control (ripple torque). The task is to design and evaluate the possibilities of the algorithm for control and acquisition speed and rotor position with the required accuracy.
12

Návrh a optimalizace řídicích algoritmů pro elektrickou brzdu s EC motorem / Design and optimization of control algorithms for an electric brake with a BLDC motor

Fiala, Martin January 2013 (has links)
This work is concerned with creating the control algorithm in microcontroller dsPIC30F6015 for electric brake with BLDC motor which will dynamically load testing BLDC motors. The work also includes programming user interface for controlling and settings parameters the control unit.
13

Bezsensorové řízení BLDC motoru / Sensorless control of BLDC motor

Hrbáč, Zbyněk January 2014 (has links)
This thesis is focused on the sensorless control of BLDC motor using the Extended Kalman filter. In the first section, process of EKF implementation for estimating rotor speed and electrical angle is described. For this estimation, EKF uses non-linear BLDC motor model and some measurement containing random noise. Second part deals with designing methodology to measure and estimate the quality of BLDC motor sensorless control. Best results were achieved with total current entering power electronics ripple analyzation. In the last section, several BLDC sensorless control algorithms were evaluated.
14

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.
15

Att skydda BLDC motorer mot oaktsam användning : Övervakning av temperatur i statorlindningar för handhållna produkter / To protect BLDC motors from inadvertent use : Temperature monitoring in stator windings for handheld products

Anders, Angrén, Jonathan, Pettersson January 2020 (has links)
Syfte – Syftet för denna studie var att utveckla en sensorlös modell som beräknar en estimeradtemperatur i en BLDC-motors statorlindningar, detta för att undersöka hur väl det går attskydda handhållna produkter mot oaktsam användning och för att kunna motverka körningunder höga temperaturer, vilket skulle kunna förlänga livslängden för handhållna produkter. Metod – Denna studie har använt forskningsmetoden Design Science Research för att utvecklaen artefakt som sensorlöst estimerar temperatur i en BLDC-motors statorlindningar.Artefaktens prestanda för den estimerade temperaturen var noggrannhet, precision ochkonvergeringstid, vilket utvärderats genom analys av kvantitativa data som samlats in underolika experiment. Resultat – Den utvecklade artefakten i studien baserades på en kombination av CurrentInjection och Lumped Parameter Thermal Network samt ett Kalman Filter, artefaktensprestanda uppfyllde inte Husqvarna AB:s krav. Artefaktens precision och noggrannhet för att estimera temperatur i en BLDCmotorsstatorlindningar blev 7,2 °C ± 23,8 °C och dess konvergeringstid blev 7,3 sför dess medelvärde och 18,4 s för dess precision. Implikationer – Denna studie och dess resultat kan användas som en hänvisning på hur välen kombination av Current Injection, Lumped Parameter Thermal Network och Kalman Filterkan estimera temperaturen i statorlindningar för BLDC-motorer med en resistans på 20 mΩ,induktans på 10 uH, nominell hastighet på ~20 000 RPM med terminering av typen Delta ochsom är icke salient. Begränsningar – Studiens begränsningar listas nedan. Utvecklingstiden för artefakten utfördes under begränsad tid. Vilket bidragit till mindre optimering av artefakterna. Vilket bidragit till färre iterationer av artefakter. Artefakten utvärderas endast på VESC hårdvara och dess mjukvara som grund.Artefaktens prestanda påverkas av noggrannheten samt precisionen vidmätning av ström och spänning. Experimenten som utfördes var begränsade. Hade intervallen som experimenten utfördes gällande temperatur, hastighetoch dynamisk last varit större skulle artefaktens prestanda kunna bli undersökti mer verkliga förhållanden. En bättre bromsbänk och en klimatkammareskulle använts. Endast en BLDC motor utvärderades. Utvärdering av fler motorer skulle kunna visa på skillnader i prestanda förartefakten mellan olika mindre motorer, det vill säga visa på dess generellatillämpbarhet. Analys av artefaktens prestanda vid enbart konvergerande tillstånd utfördes inte. Vilket skulle kunna visa på om artefaktens prestanda vid enbart konvergeradetillstånd hade uppfyllt Husqvarna AB:s krav. Nyckelord – Estimera Temperatur, BLDC-motor, Statorlindningar, Current Injection,Lumped Parameter Thermal Network, Kalman Filter, VESC / Purpose – The purpose of this study was to develop a sensorless model that calculates anestimated temperature in a stator winding of a BLDC motor, to investigate how well it is possibleto protect handheld products from inadvertent use and to be able to counteract operation underhigh temperatures, which could prolong service life of the handheld products. Method – This study has used the research method Design Science Research to develop anartifact that sensorlessly estimates temperature in a BLDC motor's stator windings. Theperformance of the artifact for the estimated temperature is accuracy, precision, andconvergence time, which was evaluated by analysing quantitative data collected during differentexperiments. Findings – The artifact developed in the study is based on a combination of Current Injectionand Lumped Parameter Thermal Network and a Kalman Filter, the performance of the artifactdid not meet Husqvarna AB's requirements. The precision and accuracy of the artifact for estimating temperature in a statorwinding of a BLDC motor was 7,2 °C ± 23,8 °C and its convergence time was 7,3 sfor its mean and 18,4 s for its precision. Implications – This study and its results can be used as a reference regarding how well acombination of Current Injection, Lumped Parameter Thermal Network and Kalman Filter canestimate the temperature in stator windings for non-salient BLDC motors with a resistance of20 mΩ, inductance of 10 uH, nominal speed of ~20 000 RPM with termination of the Deltatype. Limitations – The limitations of the study are listed below. The development time for the artifact was performed for a limited time. Which has contributed to less optimization of the artifacts. Which has contributed to fewer iterations of artifacts. The artifact is evaluated only on VESC hardware and its software as a basis.The performance of the artifact is affected by the accuracy and precision inmeasuring current and voltage. The experiments performed were limited. Had the intervals at which the experiments were performed regardingtemperature, speed and dynamic load been greater, the performance of theartifact could have been examined in more real conditions. A better brakebench and a climate chamber would be used. Only one BLDC motor was evaluated. Evaluation of more motors could show differences in the performance of theartifact between different smaller motors, that is, show its general applicability. Analysis of the performance of the artifact in convergent states alone was notperformed. Which could show if the performance of the artifact could fulfill HusqvarnaAB's requirements if the analysis were only performed in convergingconditions. Keywords – Estimate Temperature, BLDC Motor, Stator Windings, Current Injection,Lumped Parameter Thermal Network, Kalman Filter, VESC
16

Simulation and Physical Implementation of a Test Rig for Realistic Hail Impact Testing / Simulering och fysisk implementering av en stöttestningsrigg för realistiskt hagel

HERMANSSON, HANNA, WINQUIST DE VAL, ALMIDA January 2021 (has links)
Hail storms, with hail commonly near 50 mm in diameter that travel with storm wind sabove 25 m/s, cause damages of a large magnitude throughout the globe, with places like USA, Australia and India suffering the greatest. These damages have serious consequences, not least telecommunication products mounted in exposed places. Hail robustness is therefore important to test throughout a product development process, to reduce faulty products and maintenance costs. This thesis includes test rig concepts for hail impact testing and focuses on one final concept. The thesis includes a simulation model of the hail impact test rig, together with a physical implementation of the rig for comparison and validation. Additional experiments and statistical analysis is included to conclude on the accuracy and consistency with respect to realistic hail cases. The result shows that the simulation corresponds to the test rig. This physical implementation of the test rig is consistent and accurate for average sized hail projectiles, however varies more for hail projectiles corresponding to more severe storms. / Hagelstormar, med hagel omkring 50 mm i diameter och en vindhastighet på over 25 m/s, orsakar stora skador över hela världen, där USA, Australien och Indien är några av de mest utsatta platserna. Skadorna har stor påverkan, inte minst telecomprodukterna som är monterade på utsatta platser. Därav är det viktigt att testa produkter mot hagelkollisioner under produktutvecklingsprocessen, för att reducera antalet skadade produkter och kostnader. Detta examensarbete innehåller olika koncept på testriggar som simulerar hagel, med fokus på ett slutgiltigt koncept. Rapporten innehåller en simuleringsmodell av testriggen, samt en fysisk implementering av den för jämförelse och validering. Ytterliggare experiment och statistisk analys innefattas för att kunna dra slutsatser om riggens nogrannhetoch konsekventhet i föhållande till realistiska hagelstormar. Resultatet visar att simuleringen motsvarar testriggens beteende, vilket är önskvärt. Den fysiska implementationen av riggen ger ett noggrant och konsekvent resultat för medelstora hagelprojektiler, däremot fås större variationer för hagelprojektiler som förekommer i  starkare stormar.
17

Univerzální měnič na malé napětí / Universal low voltage converter

Pilch, Tomáš January 2017 (has links)
In this diploma thesis, universal inverter was manufactured and successfully tested with DC, BLDC and AC motor. Inverter is composed of the power board for driving extralow voltage supplied electric motors (from +12V to +24V) and control board with microcontroller MC56F8257. There is also explained the principle of driving DC, BLDC and AC motor as well as description of the most frequently used peripherals and inverter. components
18

Návrh výkonové, řídicí a měřicí elektroniky elektrické brzdy s EC motorem / Design of power, control and measurement electronics for an electric brake with a BLDC motor

Drbohlav, Jan January 2013 (has links)
This paper describes the design of control, measurement and power electronics department for dynamic loading of electronically commutated motors with electric brakes. After comparing the advantages and disadvantages of possible conceptions the proposal focuses on electric brake operating in generator mode and the value of load is controlled by the current dissipated in a dummy load.
19

Pohon EC motoru malého výkonu / Low power BLDC electric drive

Štajner, David January 2017 (has links)
The aim of this diploma thesis is to introduce a construction and controlling of the EC motor. On a base of knowledge make up a EC motor model in Matlab Simulink, with a position scanning providing by Hall probe. The EC motor model should be with its behavior close to the real EC motor as much as possible. There were a given requirements on the motor. On the base of those requirements was chosen a real EC motor. Its catalog values were put in the EC motor model in Matlab and the results were compared with real data. Next task was to design a real controlling driver of EC motor, which should has a minimal size. This driver was constructed and thermal test was made a on given load.
20

Digitalising The Smith Machine

Iftikhar, Rana Faheem, Amini, Sabor January 2021 (has links)
Health and fitness sector is becoming increasingly popular, and technology is being integrated into the fitness industry. This project proposed to digitalise the smith machine by creating a system to generate force through an electric motor to replace free weights. Because the exercise machine no longer needs to be loaded and unloaded with free weights, digitalisation of the smith machine will allow several users to utilise the same training machine. It will also be possible to track users' training information, such as weight lifted and the number of sets and reps performed during a workout. In this thesis, an Electrical speed controller (ESC) called VESC was used to control the BLDC motor. Experiments were conducted to find a method to control the torque. The result was producing a constant torque with a margin of error of 1-1.5 kilograms. Furthermore, two algorithms were developed where the resistance varies during the path of motion, which indicates that it is possible to develop the system to individualise resistance to improve training performance and rehabilitation. The conclusion that could be drawn is that this system can be used to replace free weights with an electric motor. / Hälso- och fitness sektorn blir allt populärare ochtekniken integreras alltmer ifitnessbranschen. Detta projekt syftar på att digitaliserasmithmaskin genom att skapa ettsystem för att generera kraft genom en elmotor föratt ersätta fria vikter. Genom att ersättalösa vikter med en elmotor så slipper användaren hanteralösa vikter vilket också underlättarför flera användaren att använda samma träningsmaskin.Det kommer också vara möjligt attspåra användarnas träningsinformation, såsom vikt,antalet set och repetitioner som utförtsunder ett träningspass.I detta projekt användes en motorstyrenhet som heterVESC för att styra en BLDC-motor.Flertalet experiment utfördes för att hitta en metodför att kontrollera vridmomentet. Dettaresulterade till att ett konstant vridmoment med enfelmarginal på 1-1.5 kilogram uppnåddes.Dessutom utvecklades två algoritmer där motståndetvarierar dynamiskt, vilket indikerar attdet är möjligt att i framtiden utveckla systemet föratt individualisera motstånd och därmedförbättra resultatet i träning och rehabilitering.Slutsatsen som kan dras är att detta system kananvändas för att ersätta fria vikter med en elmotor.

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