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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.
51

Řízení stejnosměrného motoru / Control of DC Motor

Šálek, Jan January 2014 (has links)
This diploma thesis is focused on sensorless DC motor control based on its mathematical model. This solution will be used for Honyewell actuators (type ML5410 and N10010/N05010). The aim of this thesis is to find out if there is a possibility to use this type of motor control for future to replace the existing type of motor control using Hall sensor for measuring speed of motor.
52

Řídicí jednotka pro malé DC motory s univerzálním softwarovým rozhraním / Control units for small DC motors with universal software interface

Hlouš, Jaroslav January 2008 (has links)
The purpose of this thesis is to design and implementation of the control unit for DC motors. Design is based on the concept of universal communication interface, which has been designed for simplification of communication between individual control systems. Control unit has been realized for DC motors within supply voltage range from 6 to 48 V, and maximal continuous current 2,5 A. For realization, we have used microcontroller LPC2103, and full bridge driver TLE 6209. In the thesis, we have described particular developmental steps of the control unit.
53

Jednotka pro řízení motorů dávkovacích čerpadel / Pump Control System

Streit, Jakub January 2016 (has links)
The goal of this thesis is design of universal system for motor control. This device must be able to control at least 4 motors, stepper motors or DC motors. Wired, or wireless communication, using IEEE 802.15.4, is mandatory. The System is based on modular concept. The Basic modules are Control module, Communication module, Connection module and Power module. The system was tested in the control of fertilizer dosing pumps in the greenhouse
54

Distributed control of electric drives via Ehernet

Samaranayake, Lilantha January 2003 (has links)
This report presents the work carried out aiming towardsdistributed control of electric drives through a networkcommunication medium with temporal constraints, i.e, Ethernet.A general analysis on time delayed systems is carried out,using state space representation of systems in the discretetime domain. The effect of input time delays is identified andis used in the preceding controller designs. The main hardwareapplication focused in this study is a Brushless DC servomotor, whose speed control loop is closed via a 10 MbpsSwitched Ethernet network. The speed control loop, which isapproximately a decade slower than the current control loop, isopened and interfaced to the network at the sensor/actuatornode. It is closed at the speed controller end at another nodein the same local area network (LAN) forming a distributedcontrol system (DCS). The Proportional Integral (PI) classical controller designtechnique with ample changes in parameter tuning suitable fortime delayed systems is used. Then the standard Smith Predictoris tested, modified with the algebraic design techniqueCoefficient Diagram Method (CDM), which increases the systemdegrees of freedom. Constant control delay is assumed in thelatter designs despite the slight stochastic nature in thetiming data observations. Hence the poor transient performanceof the system is the price for the robustness inherited to thespeed controllers at the design stage. The controllability andobservability of the DCS may be lost, depending on the range inwhich the control delay is varying. However a state feedbackcontroller deploying on-line delay data, obtained by means ofsynchronizing the sensor node and controller node systemclocks, results in an effective compensation scheme for thenetwork induced delays. Hence the full state feedbackcontroller makes he distributed system transient performanceacceptable for servo applications with the help of poleplacement controller design. Further, speed synchronizing controllers have been designedsuch that a speed fluctuation caused by a mechanical loadtorque disturbance on one motor is followed effectively by anyother specified motor in the distributed control network with aminimum tracking or synchronizing error. This type ofperformance is often demanded in many industrial applicationssuch as printing, paper, bagging, pick and place and materialcutting. <b>Keywords:</b>Brushless DC Motor, Control Delay, DistributedMotion Control Systems, Proportional Integral Controller, SmithPredictor, Speed Synchronization, State Feedback Controller,Stochastic Systems, Switched-Ethernet, Synchronizing Error,Time Delayed Systems, Tracking Error / NR 20140805
55

Development of a hybrid system for automatic identification of brushed direct current motors

Hamann, Franz, Mesones, Gustavo 01 September 2020 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This work proposes a low-cost hybrid hardware and software system that, through a set of methods and nested while loop fitting algorithms, allows to automatically identify the electrical and mechanical parameters of a brushed direct current motor. The aim is to facilitate a tool that contributes to the development of motion control projects in which this type of actuator is used, automating and speeding up the identification process of the motor system aiming to reach 98% accuracy, in order to guarantee a good electrical and mechanical parameter estimates for the brushed direct current motor. To achieve the objective, a platform was developed consisting of a main interface programmed in Matlab and a data acquisition hardware based on a single-phase incremental optical encoder, an H-bridge, an optocoupler circuit, and a C language-programmed DSPIC30F2010. Both parts of the platform are interconnected through the authors' own serial communication protocol.
56

Rotary parking system / Roterande parkeringssystem

Alnakar, Rayan, Catovic, Danilo January 2021 (has links)
Automatic parking systems are intended to save a lot ofspace and create a more favourable parking experience. In this thesis the main goal was to create a functional and user-friendly rotary parking system. The system consistsof a framework, DC-motor, driveline, ultrasonic distance sensor and platforms. Most of the construction consists of plastic, the remaining parts are made of metal. The system was evaluated using two experiments, one that measured the speed of the system and the other one measuring the level of accuracy. After the first experiment, it was concluded that the system works well for the corresponding speed. The second experiment showed that improvements of the accuracy can be made. / Automatiska parkeringssystem är avsedda att spara utrymme och skapa en bättre parkeringsupplevelse. I denna avhandling var huvudmålet att skapa ett funktionellt och användarvänligt roterande parkeringssystem. Systemet består av ett ramverk, likströmsmotor, drivlina, ultraljudssensor och plattformar. Majoriteten av konstruktionen består av plast, de återstående delarna är gjorda av metall. Systemet utvärderades med hjälp av två experiment, ett som mätte systemets hastighet och ett annat som mätte noggrannheten. Efter det första experimentet drogs slutsatsen att systemet fungerar bra för motsvarande hastighet. Det andra experimentet visade att förbättringar av noggrannheten kan göras.
57

Effects of Input Power Factor Correction on Variable Speed Drive Systems

Lee, Shiyoung 08 April 1999 (has links)
The use of variable speed drive (VSD) systems in the appliance industry is growing due to emerging high volume of fractional horsepower VSD applications. Almost all of the appliance VSDs have no input power factor correction (PFC) circuits. This results in harmonic pollution of the utility supply which could be avoided. The impact of the PFC circuit in the overall drive system efficiency, harmonic content, magnitude of the system input current and input power factor is particularly addressed in this dissertation along with the development of analytical methods applicable to the steady-state analysis of input power factor corrected VSD systems. Three different types of motors - the switched reluctance motor (SRM), permanent magnet brushless dc motor (PMBDC) and dc motor (DCM) are employed in this study. The C-dump converter topology, a single switch per phase converter, is adopted for the prototype SRM- and PMBDC-based VSD systems. The conventional full-bridge converter is used for DCM-based VSD systems. Four-quadrant controllers, utilizing PI speed and current control loops for the PMBDC- and DCM-based VSD system, are developed and their design results are verified with experiment and simulation. A single-quadrant controller with a PI speed feedback loop is employed for the SRM-based VSD system. The analysis of each type of VSD system includes development of loss models and establishment of proper operational modes. The magnitude of the input current harmonic spectra is measured and compared with and without a front-end PFC converter. One electromagnetic compatibility (EMC) standard, IEC 1000-3-2 which describes the limitation on harmonic current emission is modified for 120V ac system. This modified standard is utilized as the reference to evaluate the measured input current harmonics. The magnitude of input current harmonics for a VSD system are greatly reduced with PFC preregulators. While the input PFC circuit draws a near sinusoidal current from an ac source, it lowers the overall VSD system efficiency and increases cost of the overall system. / Ph. D.
58

Design of Switched Reluctance Motors and Development of a Universal Controller for Switched Reluctance and Permanent Magnet Brushless DC Motor Drives

Vijayraghavan, Praveen 03 December 2001 (has links)
Switched Reluctance Machines (SRMs) are receiving significant attention from industries in the last decade. They are extremely inexpensive, reliable and weigh less than other machines of comparable power outputs. Although the design principles of the machine are available as a concatenation of many different sources, the need for a unified, step-by-step design procedure from first principles of electromagnetics is an absolute requirement. This dissertation discusses a procedure that can be applied by engineers with a basic background in electromagnetics. Subsequent to the design of the machine, existing finite element software can do the analysis of the machine. However, this is a laborious process and the need for an analytical method is preferable to verify the design procedure before the final verification by finite elements. The analytical procedure as well as a procedure to calculate iron losses is also developed in this dissertation. A prototype machine has been developed as an example of the design process and an existing prototype is analyzed to verify the analysis procedure. The similarities between the SRM and the Permanent Magnet Brushless DC Machine (PMDBC) beg the consideration of the development of a converter that can be used to drive either machine. One such converter has been developed in this dissertation. The design of the drive for both the machines is seen to be very similar. As a consequence, a universal controller that can be used to operate both machines has been developed and implemented with a DSP. Simulations and experimental correlation for both drives have been presented. / Ph. D.
59

Utveckling av återkopplad motormodul för styrning av mätantenn : En fallstudie hos företaget Combitech AB

Evegren, Adam January 2018 (has links)
Syftet med föreliggande studie är att undersöka vilket motoralternativ som lämpar sig bäst för precis positionsstyrning av särskilda mätantenner, samt hur denna motor skall kunna drivas på ett funktionellt vis. Huvudresultatet som vill uppnås genom detta projekt är en generell motormodul kapabel att styra antennernas olika dimensioner utifrån användarens kommando genom seriell kommunikation från en PC. Studien har genomförts i samarbete med företaget Combitech AB.
60

Acionamento e controle sensorless para motores brushless DC aplicados a compressores herméticos para refrigeração doméstica / Drive and sensorless control for brushless DC motors applied to hermetic compressors for household refrigeration

Gonella, Mário Celso 18 August 2006 (has links)
O objetivo deste trabalho é desenvolver a simulação de um sistema de controle de velocidade para compressores herméticos domésticos utilizando motores brushless DC controlados por uma estratégia do tipo sensorless. O ponto central é o desenvolvimento da simulação global de controle a partir de um modelo adequado do motor BLDC com base no programa Matlab/Simulink. São abordadas algumas estratégias de controle sensorless além de alguns métodos de partida para este tipo de máquina. As estratégias de controle e partida propostas para o trabalho são analisadas detalhadamente e simuladas através do Matlab em ambiente Simulink utilizando as ferramentas do power system blockset (PSB). Os resultados destas simulações são apresentados e discutidos no final deste trabalho. / The aim of this work is to develop the simulation of a speed control system for household hermetic compressors using brushless DC motors controlled by a sensorless strategy. The main point of the work is the development of the control global simulation from a suitable BLDC motor model based on Matlab/Simulink program. Some sensorless control strategies and even some starting methods for this type of machine are approached. The control and starting strategies proposed for this work are analyzed in detail and simulated by Matlab in Simulink program using power system blockset (PSB) tools. The simulation results are presented and discussed at the end of this work.

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