Denna högskoleavhandling beskriver konstruktionen av ett system vars funktion är att PID-reglera ett linjärställdon kopplad till venturi. Syftet har varit att få fram en reglering på venturin så att förutsättningarna förblir desamma vid mätning av olika temperaturer och lufttryck i en testrigg. Denna testrigg används för att utveckla produkten Varivent som används för att uppfylla högre miljökrav på förbränningsmotorer. I arbetet beskriver jag de olika krav som funnits för att bygga det nya systemet, dessa var ingångar, utgångar, mikroprocessor, reglering, kommunikation samt övriga krav. Jag diskuterar de svårigheter och möjligheter som är förknippade med kraven och tar även upp de komponenter jag använt samt deras egenskaper. Det svåraste momentet har varit PID-regulatorn som både varit en viktig och en svårlöslig del i konstruktionen av systemet. Slutligen diskuterar jag resultatet där jag, i en analys, kan se att jag kunde underlättat för mig själv med andra angreppsvinklar men att det slutliga resultatet ändå blivit mycket tillfredsställande. / This bachelor thesis describes the design of a unit the function of which is to regulate, using PID controls, a linear mechanical adjusting screw coupled to a variable venturi flow system. The design criteria has been to create, in a test rig, a venturi control system that gives an output that is not affected by changes in either air temperature or pressure. The test rig is used for the development of Varivent, a product used to reduce the environmental impact of the internal combustion engine. In my thesis work I describe the various and necessary elements of the project. These can be termed inputs, outputs, microprocessors, regulators and communicators. I discuss the difficulties and possibilities associated with the design criteria and mention the components used and their different attributes. The most challenging part of the project has been the design of the PID regulator, which, whilst being the heart of the system, has also been the most difficult part of the system to design. Finally I discuss my results where, in an analysis, I see that I could have made things easier for myself had I approached the problems in other ways but that the final result was, despite this, very satisfactory.

No description available.

A servo system intended to steer antennas on board ships is designed, built and tested. It uses a Brushless Direct Current (BLDC) motor with an encoder to keep track of its position, and Field Oriented Control (FOC) implemented on Toshibas microprocessor TMPM373 in order to control the current flowing to the motor. The servo system will be connected in cascade to another already existing servo system and controlled with two input signals. The first signal determines if the antenna axis should rotate clockwise or counter clockwise. The second signal is a stream of pulses, where each pulse means that the motor should move one encoder point. A printed circuit board is designed and built to complete these tasks. A proportional-integral regulator is used to control the position of the motor, using the position error as the controller input. The servo system is tested. The performance of the resulting servo system is sufficient to satisfy the required position error limit of 0.5 degrees. In order to reduce the periodic disturbances presented in the system in experiments, Iterative Learning Control (ILC) is implemented. It is shown that using ILC further decreases the position error.

As the technology advances, the feature size of the modern integrated circuits (ICs) has decreased dramatically to nanometer amplitude. On one hand, the shrink brings benefits, such as high speed and low power consumption per transistor. On the other hand, it poses a threat to the reliable operation of the ICs by the increased radiation sensitivity, such as single event effects (SEEs). For example, in 2010, a commercial-off-the-shelf (COTS) BiCMOS DC/DC pulse width modulator (PWM) IC was observed to be sensitive to neutrons on terrestrial real-time applications, where negative 6-μs glitches were induced by the single event transient (SET) effects. As a result, a project was set up to comprehensively study the failure mechanisms with various test methodologies and to develop SET-tolerant circuits to mitigate the SET sensitivity. First, the pulsed laser technique is adopted to perform the investigation on the SET response of the DC/DC PWM chip. A Ti:Sapphire single photon absorption (SPA) laser with different wavelengths and repetition rates is used as an irradiation source in this study. The sensitive devices in the chip are found to be the bandgap voltage reference circuit thanks to the well-controlled location information of the pulsed laser. The result is verified by comparing with the previous alpha particle and neutron testing data as well as circuit simulation using EDA tools. The root cause for the sensitivity is also acquired by analyzing the circuit. The temperature is also varied to study the effect of the temperature-induced quiescent point shift on the SET sensitivity of the chip. The experimental results show that the quiescent point shifts have different impacts on SET sensitivities due to the different structures and positions of the circuitries. After that, heavy ions, protons, and the pulsed X-ray are used as irradiation sources to further study the SET response of the DC/DC chip. The heavy ion and pulsed laser data are correlated to each other. And the equivalent LETs for laser with wavelengths of 750 nm, 800 nm, 850 nm and 920 nm are acquired. This conclusion can be used to obtain the equivalent heavy ion cross section of any area in a chip by using the pulsed laser technique, which will facilitate the SET testing procedure dramatically. The proton and heavy ion data are also correlated to each other based on a rectangular parallel piped (RPP) model, which gives convenience in Soft Error Rate (SER) estimation. The potential application of pulsed X-ray technique in SET field is also investigated. It is capable of generating similar results with those of heavy ion and pulsed laser testing. Both the advantages and disadvantages of this technique are explained. This provides an alternative choice for the SET testing in the future. Finally, the bandgap voltage reference circuit in the DC/DC PWM is redesigned and fabricated in bulk CMOS 130nm technology and a SET hardened bandgap circuit is proposed and investigated. The CMOS substrate PNP transistor is much less sensitive to SETs than the BiCMOS NPN transistor according to the pulsed laser test results. The reason is analyzed to be the different fabrication processes of the two technologies. The laser test results also indicate that the SET hardened bandgap circuit can mitigate the SET amplitude dramatically, which is consistent with the SPICE simulation results. These researches provide more understandings on the design of SET hardened bandgap voltage reference circuit.

Le concept de l'avion plus électrique a conduit les industriels à focaliser une partie de leurs efforts sur les risques liés à l'utilisation de la haute tension dans un environnement sévère (Basse pression, large plage de température et d'humidité …). Les risques associés sont l'existence et le développement de décharges partielles conduisant à terme à la défaillance du système dans lequel, elles se produisent. Considérant cette problématique, le groupe Liebherr Elektronik GmbH, en collaboration avec le laboratoire Laplace, a lancé l'étude d'une méthode permettant de détecter les décharges partielles dans des convertisseurs destinés à des applications aéronautiques. Ce sont les résultats de ce travail qui font l'objet de cette thèse. La première partie fait état des connaissances actuelles sur les décharges partielles, de leur nature physique aux méthodes de détection utilisées. Dans la seconde partie, trois phases de mesures validant l'efficacité de la méthode étudiée sont présentées et leurs résultats sont discutés. Enfin, dans une troisième partie, les conclusions de nos travaux et leurs perspectives sont présentées. / The more electrical airplane concept led industrial companies to focus a part of their efforts on risks linked to the use of high voltage in a severe environment (Low pressure, wide range of temperature and humidity …). Associated risks are the existence and the growing of partial discharges ultimately leading to the breakdown of the system in which they occur. Considering this problematic, the Liebherr Elektronik GmbH group, in collaboration with the Laplace laboratory, launched the study of a method allowing partial discharges detection in converters intended to be used in aeronautical applications. The results of this work are the subject of this thesis. The first part brings the status of the current knowledge about partial discharges from their physical nature to the detection methods which are used. In the second part, three measurement phases assessing the efficiency of the studied method are introduced and their results discussed. Finally, in the third part, the conclusionsof our works and their perspectives are presented.

Among the different multiphase ac drive solutions, one of the most widely reported in the literature is the six-phase machine. The machines can be realised into two different configurations, symmetrical and asymmetrical. For the symmetrical configuration, the stator winding consists of two sets of three-phase windings that are spatially shifted by 60 degrees where spatial displacement between any two consecutive phases is the same and equal to 60 degrees. For the asymmetrical configuration, the two sets of three-phase windings are spatially shifted by 30 degrees. As a result, the spatial shift between consecutive phases becomes non-equidistant. In this thesis, modulation techniques for both symmetrical and asymmetrical six-phase machines are investigated. The machines are configured in open-end winding configuration where both ends of the stator winding are connected to separate isolated inverters in a topology known as dual-inverter supply. Compared to conventional single-sided supply topology where one end of the winding is connected to an inverter while the other side is star-connected, some additional benefits are offered by the dual-inverter supply topology. First, fault tolerance of the drive is improved, since the supply is realised with two independent inverters. In case one of the inverters is faulted, the other can continue to provide power to the machine. Second, the same phase voltages can be achieved with half the dc-link voltages on the two inverter inputs compared to the single-sided supply, which can be useful in applications such as electric and hybrid electric vehicles and medium sized ships, where the dc voltage levels are limited. Further, due to the nature of the topology, additional diodes and capacitors like in the Neutral Point Clamped (NPC) and Flying Capacitor (FC) VSIs are not required. The latter results in a further advantage - capacitor voltage balancing techniques are not required. Two pulse width modulation (PWM) techniques for control of the dual-inverter supplied six-phase drives are proposed in this thesis. The first is a reference sharing algorithm where the inverters are modulated using reference voltage that is shared equally and unequally between the two modulators. For both symmetrical and asymmetrical six-phase drives, a better performance, in term of total harmonic distortion (THD) of phase voltage is obtained when the reference is shared unequally between the two modulators. The second technique is carrier-based modulation where the modulation of the two inverters is determined by the disposition of the carrier signals. Three variations of carrier signals disposition are investigated namely; the phase disposition (PD-PWM), alternate phase opposition disposition (APOD-PWM) and phase-shifted PWM (PS-PWM). For the symmetrical six-phase drive, the best phase voltage and current THDs are obtained using APOD-PWM while for asymmetrical six-phase drive, the APOD-PWM produces the worst current THD despite having the best voltage THD among the three methods. All the developed modulation techniques are analysed using simulations and experiments undertaken using a laboratory prototypes. The waveforms and spectra of phase voltage and load current obtained from the simulation and experimental works are presented in this thesis together with the THD of both the voltage and current over entire linear modulation range.

Orientador: Dionizio Paschoareli Junior / Banca: Falcondes Jose Mendes de Seixas / Banca: Hari Bruno Mohr / Resumo: A tendência dos sistemas de energia elétrica é uma operação cada vez mais próxima de seus limites operacionais. A presença de equipamentos que utilizam a eletrônica de potência, no controle e condicionamento da energia, é cada vez mais freqüente. A utilização de conversores como fonte de tensão, associados a elementos armazenadores de energia como, por exemplo, a bateria de sódio-enxofre, com alta densidade de energia, alta eficiência na carga e descarga e ainda um longo ciclo de vida, é a configuração básica de um Compensador Regenerativo de Potência Ativa. Compensação regenerativa de potência é um conceito que permite o armazenamento de energia em períodos favoráveis sob o ponto de vista dos custos da energia elétrica. Este conceito de compensação baseia-se no armazenamento da energia excedente ao longo do dia, nos períodos de menor tarifação, para utilizá-la nos horários de ponta (sobre-tarifa), aproveitando-se as vantagens contratuais de consumo de energia fora de ponta e promovendo-se uma melhor equalização de consumo, permitindo uma redução no contrato de demanda. Portanto, na compensação regenerativa de potência ativa, os períodos de consumo de energia são deslocados, com o objetivo de se obter redução na tarifa. Este conceito mostra-se interessante em sistemas com tarifação do tipo horo-sazonal, como é o caso brasileiro. Com o objetivo de se verificar tal troca de potência ativa, um modelo trifásico foi implementado e simulado. Os controles da potência ativa trocada entre o compensador e o sistema e da tensão na barra na qual o mesmo está instalado são realizados independentes e por controladores do tipo PID. Os sinais de controle dos interruptores semicondutores que compõe o conversor como fonte de tensão são gerados a partir do DSP TMS320F2808 da Texas Instruments, o que está embarcado no módulo didático eZdsp F2808 da Spectrum Digital / Abstract: Nowadays, electric power systems are expected to work closer to their operating limits. Power electronics based controllers, such as voltage sourced converters, are increasingly present in power systems. Electronic devices are often used to energy controlling and conditioning. The use of voltage sourced converters, associated to high-density storage elements, is the basic configuration of a Regenerative Active Power Compensator. Regenerative Active Power Compensator is a concept which proposes the energy storage as a possibility for revaluation of electrical energy cost with demand contracts. This concept is based on storing energy surplus during off peak periods, when the energy cost is cheaper, and injecting it back to the system during the overpriced peak periods. This procedure allows a better equalization of energy consumption and a reduction in electric power demand contracts. Therefore, using regenerative active power compensation, the consumption is dislocated from peak periods, resulting in a reduction of energy costs for the consumer. This concept is especially attractive for countries that use hour-seasonal fees police, as in the Brazilian case. This work proposes a three-phase model simulation with digital signal processor controller to investigate the active power flow control between the power system and the compensator, using a proportional-integral-derivative control strategy. The control signals are generate using the Texas Instruments DSP TMS320F2808, witch is embedded into the eZdsp F2808 didactic module, from Spectrum Digital / Mestre

Made available in DSpace on 2014-12-17T14:55:42Z (GMT). No. of bitstreams: 1 LucianoPSJ_DISSERT.pdf: 6664942 bytes, checksum: fc1840aaaecdac8b8558e271f979adbf (MD5) Previous issue date: 2009-04-17 / This work deals with the development of an experimental study on a power supply of high frequency that provides the toch plasmica to be implemented in PLASPETRO project, which consists of two static converters developed by using Insulated Gate Bipolar Transistor (IGBT). The drivers used to control these keys are triggered by Digital Signal Processor (DSP) through optical fibers to reduce problems with electromagnetic interference (EMI). The first stage consists of a pre-regulator in the form of an AC to DC converter with three-phase boost power factor correction which is the main theme of this work, while the second is the source of high frequency itself. A series-resonant inverter consists of four (4) cell inverters operating in a frequency around 115 kHz each one in soft switching mode, alternating itself to supply the load (plasma torch) an alternating current with a frequency of 450 kHz. The first stage has the function of providing the series-resonant inverter a DC voltage, with the value controlled from the power supply provided by the electrical system of the utility, and correct the power factor of the system as a whole. This level of DC bus voltage at the output of the first stage will be used to control the power transferred by the inverter to the load, and it may vary from 550 VDC to a maximum of 800 VDC. To control the voltage level of DC bus driver used a proportional integral (PI) controller and to achieve the unity power factor it was used two other proportional integral currents controllers. Computational simulations were performed to assist in sizing and forecasting performance. All the control and communications needed to stage supervisory were implemented on a DSP / O presente trabalho trata do desenvolvimento de um estudo experimental sobre uma fonte de alimenta??o de alta freq??ncia que alimentar? a tocha pl?smica a ser implementada no projeto PLASPETRO, o qual consta de dois conversores est?ticos desenvolvidos com o uso de transistores - Insulated Gate Bipolar Transistor (IGBT). Os drivers utilizados no controle dessas chaves s?o acionados por um controlador de sinal digital - Digital Signal Processor (DSP) atrav?s de fibras ?pticas a fim de reduzir problemas com interfer?ncia eletromagn?tica - Electromagnetic interference (EMI). O primeiro consiste de um est?gio pr?-regulador na forma de um conversor CA-CC boost trif?sico com corre??o de fator de pot?ncia, tema principal deste trabalho, enquanto o segundo consiste na fonte de alta frequ?ncia propriamente dita. Um inversor s?rie-ressonante composto por 4 (quatro) c?lulas inversoras operando a uma frequ?ncia de cerca de 115 kHz cada, em modo de comuta??o suave, alternando-se para fornecer ? carga (tocha de plasma) uma corrente alternada com uma frequ?ncia de 450 kHz. O primeiro est?gio tem a fun??o de fornecer ao inversor s?rie-ressonante uma tens?o CC de valor controlado a partir da rede de alimenta??o disponibilizada pelo sistema el?trico da concession?ria, al?m de corrigir o fator de pot?ncia do sistema como um todo. Esse n?vel CC de tens?o no barramento de sa?da do primeiro est?gio ser? utilizado para o controle da pot?ncia transferida pelo inversor ? carga, podendo variar desde 550Vcc at? um valor m?ximo de 800Vcc. Para controlar o n?vel de tens?o do barramento CC utilizou-se um controlador Proporcional Integral (PI) e para atingir o fator de pot?ncia unit?rio utilizou-se dois outros PIs para controle das correntes em referencial estacion?rio. Simula??es computacionais foram realizadas para auxiliar no dimensionamento e previs?o de performance. Todo o controle e comunica??es necess?rias ao est?gio supervis?rio foram implementadas em um DSP

With advancement in automotive systems, it is not just the combination of mechanical devices like in old days. Almost all the systems of today's modern car are controlled electronically by a number of ECUs (Electronics Control Unit) with the combination of sensor modules. To exchange information between the ECU and sensor modules a number of communication standards are used. The most commonly used standards are CAN, LIN, and PWM etc. The data transmission between the ECU and sensor modules can be easily established with a PWM (Pulse Width Modulation) techniques in comparison with CAN or LIN. PWM provide a convenient solution in terms of cost and performance when the data-rate is up to 10-bits. While for higher resolution data rates its performance is not satisfied. Extra effort is needed to implement diagnostic information for the integrity of data. Also, the accuracy of PWM signal is dependent on the noise voltage and channel bandwidth. In 10-bit system a single bit is represented by 4mV which face serious problem in automotive system due to the noise voltage pulses which effect the resolution of the PWM. The alternative solution for safe and high data rate which is more than 10-bit resolution is to used CAN and LIN protocols. Both CAN and LIN have availability of diagnostic modes for an ensured data transmission. Also, their capabilities for interconnecting a number of nodes (sensors-modules) on the same network can significantly reduce the wiring cost. But in automotive a number of systems need to communicate through point-to-point link, and it seem to be too expensive to used CAN and LIN for point-to-point communication because of its development complexity and wiring cost for a standalone system. To overcome these issues and to provide an alternative low-cost solution the SAE (Society of Automotive Engineers) developed a 3-wire new digital point-to-point protocol called SENT. SENT (Single Edge Nibble Transmission) Protocol is now an international standard (SAE J2716). SENT is unidirectional point-to-point communication protocol, which can be used for high resolution data transmission between sensor module and ECU. The data are transmitted by sensor module in a series of pulses each pulse is 4-bit (one nibble) long and the data are measured between two falling edges by the receiving module. There are total of nine pulses which defined the SENT frame. The first pulse is called calibration pulse, it is used for compensating to recalibrate all the other pulses in case of transmitter clock deviation, this is the best feature of SENT and can be implemented in the decoder design. This thesis work focuses on the development of SENT protocol decoder and its signal robustness analysis in comparison with the conventional PWM signal. Our first goal is to developed SENT-Protocol decoder in software on the available microcontrollers is to check how much memory foot print is used and how much the processor overhead. Two platforms have been used for this purpose. First, two implementation designs prototype were made with fixed-point and floating-point development techniques on the 32-bit platform for SENT decoder. Secondly SENT-decoder were developed with 8-bit platform and compared with the two previous designs to check how much memory foot print is used and how much is the processor overhead. Finally, the signal integrity analysis has been performed for PWM and SENT signal using spice simulation. The purpose is to check the maximum data rate limit that the PWM signal support without creating any bit error in the transmitted signal. The same data rate is then used for SENT signal to be compared with PWM signal.

This report describes the manufacture and control of a flying platform. The report describes the basic and fundamental theories required to get the platform flying. It touches on subjects such as A/D-conversion. PWM-control and PID-control. The sensors used in the platform are a gyro and an accelerometer. The platform is controlled from a ground station through a wireless link. The wireless link is an Xbee-module that implements the ZigBee-protocol. The microprocessor used is the Atmega 128 by Atmel. An indirect complementary filter is used to get the angle of the platform. For the platform to be able to balance a more thourough analysis of the gyro is required. This sensor proved to be more difficult to handle than first anticipated. Every component except the gyro worked as expected. Every algorithm and method reported in this work have been implemented and tested in software.