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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.
31

Návrh synchronního motoru s vnějším rotorem a s permanentními magnety / Design of outrunner PMSM

Dudáš, Juraj January 2015 (has links)
The diplomatic thesis will describe the principle functions of synchronous motors with permanent magnets, for therein analysis of PMSM and BLDC motors. We will make calculation of the required parameters from the power unit for glider Discus 2. We will create a design of BLDC and PMSM motor from specified parameters. Features of the proposed engines will be verified with the help of the programs FEMM, RMxprt, Maxwell. At the end of the work will make conclusion about the diplamatic project and diffrences between PMSM and BLDC motor.
32

Control and balancing of a small vehicle with two wheels for autonomous driving

Batmanian, Saro, Naga, Pasam January 2019 (has links)
Control and balancing of an inverted pendulum has gained a lot of attention over the past few decades due to its unstable properties. This has become a great challenge for control engineers to verify and test the control theory. To control and balance an inverted pendulum, proportional integrated derivative (PID) method or linear quadratic regulator (LQR) method can be used through which a lot of simulations can be done using the represented theories.Since urban population is increasing at a very alarming rate, there is a need to discover new ways of transportation to meet the future challenges and demands. Scania has come up with a new conceptual bus called NXT which aims to develop a modular vehicle that should configure and re-configure themselves between different transportation tasks. NXT vehicle has front and rear drive modules which can be represented as single axle, two-wheeled vehicles which in-turn can be viewed as an inverted pendulum with a huge Center of Gravity. Controlling and balancing of the pod or drive module precisely and accurately is an interesting challenge since it is an unstable inverted pendulum with huge center of gravity (COG). This behaviour of the system has created a research question whether the module is controllable or not.Therefore this thesis focuses on the possibility of controlling the pod which is a two-wheeled inverted pendulum vehicle with a COG offset. Also, the thesis focuses on the construction, mod-elling, testing and validation of a down-scaled model, what sensors are needed to balance the pod precisely, how the sensors must be integrated with the system and how the pod can be controlled remotely from a certain distance by a human. The developed pod houses the technologies like sensors, BLDC motor controllers, hoverboard, Arduino board and Bluetooth transmitters.The Master Thesis starts by presenting an introduction to the inverted pendulum theories, Scania NXT project, information about the research methods, thesis outline and structure . It continues by describing related literature about the inverted pendulums, segways, hoverboards, motor controllers and Arduino boards. Afterwards, the process of deriving a mathematical model, together with simulation in Matlab, Simulink and Simscape is described. Later, construction of the pod is made and lot of effort is put to run the pod. Since the pod needs to be controlled remotely by a human, a remote controlled systemis implemented via mobile phone using an app and finally the thesis is finished with a conclusion and ideas for future work. / Reglering och balancering av en inverterad pendel har väckt stor uppmärksamhet över de senaste decennierna på grund av dess instabila egenskaper. Det har skapat stora utmaningar för regleringenjörer eftersom området tillåter test och verifikation av diverese lösningar. För reglering och balansering av en inverterad pendel, så kan en regulator med proportionell, integral och derivat (PID) konstanter eller en linjär kvadratisk regulator (LQR) användas tillsammans med simuleringar för att bekräfta teorin.I och med att stadsbefolkningen ökar i mycket hög takt, så uppstår behovet av att uppfinna nya transportmedel för att lösa framtida utmaningar och krav. Scania har tagit fram en ny konceptbuss som heter NXT, med målet att utveckla ett modulfordon som kommer att konfigurera och rekonfigurera sig själva mellan olika transportuppgifter. NXT-fordonet har fram- och bakdriv-moduler som kan representeras som enaxlade tvåhjuliga fordon, vilka i sin tur kan betraktas som en inverterad pendel med en stor massa. Att reglera och balansera drivmodulen på ett noggrant sätt är en utmaning eftersom det är ett mycket instabilt system med enorm massa och en okänd tyngdpunkt. Systemets beteende har skapat en forskningsfråga om modulen är reglerbar eller inte.Denna uppsats fokuserar därmed på möjligheterna att kunna reglera drivmodulen samt vilka begränsningar det finns. Uppsatsen fokuserar också på konstruktion, modellering, testning och validering av en nedskalad modell, vilka sensorer som krävs för att balansera drivmodulem, samt hur sensorerna måste integreras med systemet för att kunna fjärstyra fordonet från ett visst avstånd. Utveckingen av en sådan nedskalad modell berör olika områden såsom sensorer, BLDC-motorstyrenheter, hoverboard balanserings scootrar, Arduino kretskort och Bluetooth-sändare/mottagare.Uppsasten börjar med en introduction om olika inverterade pendel teorier, Scania NXT project, forskningsmetoder, en översikt och övergripande struktur. Vidare fortsätter beskrivining av relaterade litteratur om inverterade pendel, Segway, hoverboard, borstlösa motor styrenheter och Arduino kretskort. Senare fortsätter processen för att härleda matematiska modeller som beskirver systemet, tillsammans med simuleringar i Matlab, Simulink och Simscape. Därefter beskrivs konstruktionen av en nedskalad modell av drivmodulen och beskrivning av nödvändiga processer för att få hårdvara och mjkukvara att fungera ihop. Då fordonen ska ha möjlighet att fjärrstyras, så implementerades en bluetooth enhet tillsammans med en programmerbar mobil applikation. Slutligen avlutas uppsatsen med resultat, slutsats och diskussioner och förslag till framtida arbeten.
33

Použití bezkartáčového stejnosměrného motoru pro pohon lineárního servopohonu s bezpečnostní funkcí / Using brushless d.c. motor to drive servo-unit with safety function

Rudolf, Ladislav January 2012 (has links)
In this work, a proposal for BLDC motor control, which will be used as a drive linear actuator. Control with microcontroller focuses mainly aspects such as motor mode, regenerative mode, measuring rotor position sensors and measuring the motor current, which corresponds to the moment. The result of the work is focused on upgrading the existing Honeywell actuator, where the processor-controlled BLDC motor to replace the existing system and take over the actuator working function and emergency function.
34

Fault detection of planetary gearboxes in BLDC-motors using vibration and acoustic noise analysis

Ahnesjö, Henrik January 2020 (has links)
This thesis aims to use vibration and acoustic noise analysis to help a production line of a certain motor type to ensure good quality. Noise from the gearbox is sometimes present and the way it is detected is with a human listening to it. This type of error detection is subjective, and it is possible for human error to be present. Therefore, an automatic test that pass or fail the produced Brush Less Direct Current (BLDC)-motors is wanted. Two measurement setups were used. One was based on an accelerometer which was used for vibration measurements, and the other based on a microphone for acoustic sound measurements. The acquisition and analysis of the measurements were implemented using the data acquisition device, compactDAQ NI 9171, and the graphical programming software, NI LabVIEW. Two methods, i.e., power spectrum analysis and machine learning, were used for the analyzing of vibration and acoustic signals, and identifying faults in the gearbox. The first method based on the Fast Fourier transform (FFT) was used to the recorded sound from the BLDC-motor with the integrated planetary gearbox to identify the peaks of the sound signals. The source of the acoustic sound is from a faulty planet gear, in which a flank of a tooth had an indentation. Which could be measured and analyzed. It sounded like noise, which can be used as the indications of faults in gears. The second method was based on the BLDC-motors vibration characteristics and uses supervised machine learning to separate healthy motors from the faulty ones. Support Vector Machine (SVM) is the suggested machine learning algorithm and 23 different features are used. The best performing model was a Coarse Gaussian SVM, with an overall accuracy of 92.25 % on the validation data.
35

Střídač pro trojfázový motor / Iverter for three-phase motor

Mikuška, Martin January 2014 (has links)
This master’s thesis goes into design of particular circuits for three phase inverter. Inverter’s control is ensured by digital signal controller MC56F8013 with his program. Principle of control is suggested for individual motors. Inverter design considerate universal use and capability for any three phase motor. Particular blocks are compatible each other.

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