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Modeling and Control of Electromechanical Actuators for Heavy Vehicle ApplicationsPettersson, Alexander, Storm, Patrik January 2012 (has links)
The possibility to develop control systems for electromechanical actuators at Scania is studied, in particular the focus is on how to exchange the intelligent actuators used today with dumb ones. An intelligent actuator contains its own control electronics and computational power, bought as a unit from suppliers by Scania and controlled via the CAN bus. A dumb actuator contains no means of controlling itself and its I/O is the motor’s power pins. Intelligent actuators tend to have limited control performance, time delays and poor diagnose systems, along with durability issues. A dumb actuator could have the benefit of avoiding these disadvantages if the system is designed within the company. A literature study concerning the different types of electrical motors available and their control methods is performed, the most suitable for use in a heavy vehicle is deemed the brushless DC motor, BLDC. An intelligent throttle is chosen for a case study and has its control electronics stripped and replaced with new sensor- and control cards. The case study is used to investigate the possibilities and difficulties of this design process. A simulation model is developed for the electronics, motor and the attached mechanical system. With the aid of this model a controller architecture is designed, consisting of PI controllers with feed-forward and torque compensation for nonlinearities. The developed controller architecture is tested and in theory it can compete with the intelligent throttle’s performance. The model is also adapted to allow for code generation. The simulation model is used to study some common electrical faults that can effect the system and the possibilities for diagnosis and fault-remedial actions. The hardware prototype system shows that a current controller is necessary in the control architecture to achieve decent performance and the prototype is developed in such a way as to make future studies possible. The conclusion of the thesis is that Scania would be able to design control systems for dumb actuators, at least from a technical perspective. However more studies, from an economical point of view, will be necessary.
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IEEE 802.11n MIMO Modeling and Channel Estimation ImplementationXu, Xin January 2012 (has links)
With the increasing demand of higher data rate for telecommunication, the IEEE802.11n standard was constituted in 2009. Themost important character of the standard is MIMO-OFDM, which not only improves the throughput but also the spectrumefficiency and channel capacity. This report focuses on the physical layer IEEE802.11n model. By utilizing an existingSimulink based IEEE802.11n system, functionalities like MIMO (up to 4*4), OFDM, STBC, Beamforming, and MMSEdetector are simulated. The results such as bit error rate, packet error rate and bit rate with different system settings are given.Furthermore, the channel estimation process is clarified, and a DSP builder based MMSE detector is realized, which can fulfillexactly the same function as the Simulink model.
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Cylinder-by-Cylinder Torque Model of an SI-Engine for Real-Time Applications / Cylinderindividuell Momentmodell för RealtidstillämpningarHashemzadeh Nayeri, Mohit January 2005 (has links)
In recent years Hardware-in-the-Loop HiL, has gained more and more popularity within the vehicle industry. This is a more cost effective research alternative, as opposed to the tests done the traditional way, since in HiL testing the idea is to test the hardware of interest, such as an electronic control unit, in a simulated (or partially simulated) environment which closely resembles the real-world environment. This thesis is ordered by Daimler Chrysler AG and the objective of this thesis is the developing of a cylinder-by-cylinder model for the purpose of emulation of misfire in a four-stroke SI-engine. This purpose does not demand a precise modelling of the cylinder pressure but rather an adequate modelling of position and amplitude of the torque produced by each cylinder. The model should be preferebly computaionally tractable so it can be run on-line. Therefore, simplifications are made such as assuming the rule of a homogenous mixture, pressure and temperature inside the cylinder at all steps, so the pressure model can be analytical and able to cope with the real-time demand of the HiL. The model is implemented in Simulink and simulated with different sample rates and an improvement is to be seen as the sample rate is decreased.
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Simulation and Evaluation of a DVB system using simulink (Vol I)Isla Hernandez, Sergio January 2005 (has links)
DVB (Digital video broadcasting) is the television digital system. It's however much more than a simple replacement for existing analogue television transmission, this system has many advantages such as picture quality and allows you a range of new features and services including subtitling, multiple audio tracks, interactive content, multimedia content... The system is based in the OFDM technology, which allows DVB system to exploit the spectrum frequencies in a better way, saving spectrum, but OFDM has an important drawback that is the peak to average power ratio problem. OFDM is based on the FFT algorithms generating several orthogonal subcarriers. This thesis talks about the improvement of the PAPR problem using the clipping method. The simulation has been developed in Simulink® and Matlab®. With all the information presented in this thesis, any user can simulate the system. Thus, this thesis can be improved using other using other techniques to solve the PAPR problem.
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Modellering i SIMULINK av synkronisering i nätverk enligt IEEE802.11aYousef, Michael Mousa January 2005 (has links)
Inom detta examensarbete implementeras i SIMULINK en modell av ett trådlöst överföringssystem enligt IEEE802.11a standarden. Modellen klarar av att hantera störningskällor som är vanligt förekommande i den miljö applikationen operar på. Denna modell utvärderas sedan för att avgöra dess belastningsförmåga och vid vilka värden den brister. Första delen av rapporten beskriver målsättningen och syftet med detta examensarbete, samt metodvalet och rapportens uppläggning som tillämpats. Rapportens andra del innehåller en allmän beskrivning av digital radiokommunikation och OFDM-baserade system. Därefter beskrivs teorin av både sändaren och mottagaren enligt IEEE802.11a standarden. Slutligen behandlas ett flertal vanligt förekommande synkroniseringsalgoritmer som har blivit publicerade. I rapportens tredje del diskuteras de verktyg som har använts för att bygga modellen. Denna del fortsätter sedan med att kort beskriva valen av de algoritmer som har tillämpats i modellen. Fjärde och sista delen av rapporten delas in i två kapitel. I första kapitlet sker de simuleringar som erfordras för att kunna utvärdera modellen. Examensarbetet knyts sedan ihop vid resultatkapitlet, där även förslag på fortsatt arbete diskuteras. / En ny version av examensarbetet har lagts till i listan (nr. 2) på begäran av författaren med anledning av att författaren har bytt namn.
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Modelling and implementation of an MPEG-2 video decoder using a GALS design path.Rosengren, Kaj January 2006 (has links)
As integrated circuits get smaller, faster and can fit more functionality, more problems arise with wire delays and cross-talk. Especially when using global clock signals distributed over a large chip area. This thesis will briefly discuss a solution to this problem using the Globally Asynchronous Locally Synchronous (GALS) design path. The goal of this thesis was to test the solution by modelling and partially implementing an MPEG-2 video decoder connected as a GALS system, using synchronous design tools. This includes design of the system in Simulink, implementing selected parts in VHDL and finally testing the connected parts on an FPGA. Presented in this thesis is the design and implementation of the system as well as theory on the MPEG-2 video decoding standard and a short analysis of the result.
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The Integration of MATLAB and Embedded Controller for Control ApplicationSun, I-chin 03 February 2004 (has links)
In recent years, the requirement for embedded controllers has been steadily on the increase due to the development of computers, communication and consumptive products. In order to overcome the pressure of short life-time and rapid changing rate of products, however, related industries have been engaged in improving their design to shorten the time to market and to lower the cost. Therefore, a new concept, rapid controller prototyping, has been proposed to solve the problem with the development of controllers. However, most of the proposals are expensive and restricted in the choice of software and hardware, and aren¡¦t adequate for research.
To solve the problems above, this paper has chosen MATLAB/Simulink, Real-Time Workshop, a software widely used by the academic community, as tools to study rapid controller prototyping. Here, we also focus on the establishment of the developing platform. Then we design, simulate and test the controller on the platform established. Finally, we apply the controller to the physical plant. By doing so, this paper expects to solve current problems in the development of controllers.
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Dynamic Simulation and Economic Analysis of an Isolated Hybrid Wind Diesel SystemSelony, Wilson 24 June 2008 (has links)
An isolated hybrid system comprised of a dispatchable and a non-dispatchable power generation sources, is proposed to supply the load of a remote village in the west region of Haiti. The wind speed data and load data of this remote village are used to study the system. The non-dispatchable generation comes from a nature-dependent wind turbine, and the dispatchable one is a diesel generator. Using MATLAB/Simulink, dynamic simulations are performed to investigate the interaction between these two power sources for the load management, and the voltage and frequency behaviors during wind speed and load variations. Economic analyses of the
system are also conducted. The cost of energy (COE), energy payback time (PBT), internal rate of return (IRR) and avoided cost (AC) of CO2¬, NOx and PM (Particles Materials) of the hybrid system are computed, and results are compared with those of the baseline diesel only case. Simulation results show that the wind turbine and the diesel generator can be operated suitably in parallel, and the economic analyses show the positive benefits of wind generation in reducing COE and increasing the avoided
cost (AC) of emitted pollutions.
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Modeling, Simulation and Optimization of Residential and Commercial Energy SystemsBregaw, Mohamed Abdussalam 12 August 2013 (has links)
A Residential Energy Management System (REMS) in smart grid provides capability to manage a daily load curve in order to reduce power consumption and energy cost. Consequently, (REMS) offers significant benefits for both the electricity suppliers and consumers in terms of control and schedule time of use of major appliances.
In recent years, however, the rate of energy demand has increased rapidly throughout the world while the price of energy has been fluctuating. Numerous methods for (REMS) are used; this thesis analyzes many candidate scenarios during peak load periods comparing to the tariff to reduce the usage and its associated costs. It presents simulated results of proposed (REMS) to provide an automated least cost demand response. The main approach will be to ensure the satisfaction of the requirements with constraints on efficient use of energy. Multiphasic system behaviors of smart appliances in (REMS) with a realistic manner are proposed. / This thesis examines many mathematical models of home appliances in order to calculate the physical quantities that reflect the parameters’ impact and the system behavior. Main contribution determines the optimal solution of (TOU) problem to reduce energy cost and determine the best operation time by using (Linear optimization technique).
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FPGA BASED IMPLEMENTATION OF A POSITION ESTIMATOR FOR CONTROLLING A SWITCHED RELUCTANCE MOTORPampana, Srilaxmi 01 January 2004 (has links)
Rotor Position information is essential in the operation of the Switched Reluctance Motor (SRM) for properly controlling its phase currents. This thesis uses Field Programmable Gate Array (FPGA) technology to implement a method to estimate the SRMs rotor position using the inverse inductance value of the SRMs phases. The estimated rotor position is given as input to the Commutator circuit, also implemented in the FPGA, to determine when torque-producing currents should be input in the SRM phase windings. The Estimator and Commutator design is coded using Verilog HDL and is simulated using Xilinx tools. This circuit is implemented on a Xilinx Virtex XCV800 FPGA system. The experimentally generated output is validated by comparing it with simulation results from a Simulink model of the Estimator. The performance of the FPGA based SRM rotor position estimator in terms of calculation time is compared to a digital signal processor (DSP) implementation of the same position estimator algorithm. It is found that the FPGA rotor position Estimator with a 5MHz clock can update its rotor position estimate every 7s compared to an update time of 50s for a TMS320C6701-150 DSP implementation using a commercial DSP board. This is a greater than 7 to one reduction in the update time.
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