The diploma thesis deals with the simulation of induction motor control with respect to high efficiency. The theory of an induction motor is described here, with emphasis on its losses. Scalar and vector control are also described here. Vector control is optimized for higher efficiency. Subsequently, the creation of a model in the program MATLAB - Simulink is described here, for the comparison of vector control with and without optimization.

The construction sector is responsible for 20% of Greenhouse Gas (GHG) emissions, of whichdiesel-powered construction equipment are large contributors. Currently there are many ongoing Fuel Cell (FC) powered construction equipment projects as it is seen as an attractiveoption to power the futures zero-emission heavy-duty machines. Although an attractivealternative, hydrogen FC has drawbacks such as releasing liquid water and water vapor viathe exhaust as a byproduct which in their working environment can cause a suite of issues. Agap in the literature on the water exhausted is present and therefore this degree project seeksto investigate the amount, and ratio, of liquid water and water vapor released from threetypical construction equipment drive cycles which would allow further investigation onappropriate management. The method used for this degree project was to modify a pre-mademodel in Simulink built with Simscape blocks. The model was modified to represent a FCsystem used in a test-rig by implementing experimental and measured data for design andoperating parameters. Different pressures, temperatures, and cathode inlet RelativeHumidity (RH) were investigated to find their effect on the performance and water in theexhaust. A sensitivity analysis of different unknown parameters was also conducted tounderstand their influence on the results. For the reference case, the results showed that foran articulated hauler, the water in the exhaust was 26% liquid which translates to 8.6 kg for a1-hour drive cycle. The crawler excavator and wheel loader, both had 30-minute drive cyclesand had 1.1 kg liquid water with a liquid water ratio of 7% and 0.7 kg liquid water with aliquid water ratio of 5% in the exhaust respectively. For a full 8-hour workday with twoparallel FCs connected, the articulated hauler liquid water amount is 137.6 kg, the crawlerexcavator 35.2 kg, and the wheel loader 22.4 kg. Overall, it was found the liquid water ratiocould be changed to a large extent with different operating parameters, where thetemperature had the greatest influence. The system and stack efficiencies did not changeconsiderably with different operating parameters, meaning that the total water in the exhaustremained similar for the different respective drive cycles.

The next generation of Autonomous Underwater Vehicles (AUV) can impact our observation of the world. The flight simulation and full-envelope hydrodynamics modeling can improve the performance of AUVs in terms of control, navigation and positioning. In order to achieve agile maneuverability, a more accurate database of full-envelope hydrodynamic coefficients is supposed to be generated. Two semi-empirical methods, Jorgensen and DATCOM, and two numerical method, Computational Fluid Dynamics (CFD) and XFLR5 are used to push the boundaries of hydrodynamic coefficients: lift, drag and moment coefficients for flight-style AUVs at the Swedish Maritime Robotics Center (SMaRC). A comparison of different approaches and tools, and an analysis of the most appropriate approaches for different regions of a defined maneuver has been conducted in this thesis. A data confidence level was proposed as a way to estimate the accuracy of the data and a structured database was built in terms of data confidence level. Different components of the AUV such as the hull body and wings were analyzed separately. The new database is input to a 3DOF Simulink model and the 6DOF SMaRC hydrobatics simulator for flight dynamics simulations. Simulations show that the new database has a good applicability.

Conveyor chains are often subject to repetitive shock loads during normal operations. This can cause accelerated wear in the chain leading to premature chain replacementor chain failure (Otoshi, 1997, p. 4). In this thesis a new approach for reducingshock load related wear in conveyor chains is proposed. The scope and objective ofthis project is to investigate the shock load phenomenon and develop a dynamic pinlink chain plate. A study into chain wear and shock loads of chain driven conveyorswas made to identify problem areas. Additionally, a Simulink model was created tosimulate the influence of shock loads on conveyor chains. Common wear as a result ofshock loads are identified as pin failure, bushing failure, scuffing, chain plate failure,fatigue and chain elongation, (Otoshi, 1997, p. 76-78). Nine concepts were drafted and evaluated using methods described in (Ulrich &Eppinger, 2016). The concepts were simulated using Finite Element Analysis (FEA)and two concept iterations, Concept B v.3 and Concept C v.3, were manufacturedfor static tensile tests using two different setups and Digital Image Correlation (DIC)system for additional strain measuring. The breaking load for Concept B v.3 andConcept C v.3 is 105 and 70 kN respectively. The approximate yield strength ofConcept B v.3 is 11 kN and 40 kN for Concept C v.3. The Fatigue limit was estimatedto 10 kN for Concept B v.3 and 20 kN for Concept C v.3. A nonlinear FEA for Concept C v.3 and Concept B v.3 provided additional insightinto the behaviour of the pin link chain plates during high stress concentrations. While neither the linear static nor nonlinear static analyses managed to accuratelypredict the behaviour of Concept B v.3, the simulated results of Concept C v.3 werein line with the observed tensile tests. From the results it is concluded that a dynamic chain plate in the form of ConceptC v.3 has the potential to reduce the magnitude of the force in the chain imposedby shock loads, while still following the current ISO standard for conveyor chains. The resulting design proposition provides an easy to manufacture high strength chainplate with increased elastic properties.Future work should be focused on determining the fatigue life and shock load resistanceof the developed chain plate. It is recommended that material selection is focused onwear and fatigue resistant materials and that both simulated and physical dynamictesting is performed.

Software-defined radio is a continuously developing technology applied in fields of mobile communications and among others. It is a radio communication system where software is used to implement parts of its functionality in an embedded system or computer. Devices which can transmit and receive different radio protocols based on software has major advantages. The ability to be able to reconfigure and change functionality on the fly to adapt to different environments is suited for multiple different applications, one of such is the environment in space. Distortions such as phase, frequency and timing offset all occur in such environment. The effects of these distortions can be reduced using different synchronization techniques in the receiver. A polyphase symbol timing synchronizer with two different timing error detectors, is designed in Simulink consisting of an 8-tap polyphase filter bank, a zero-crossing or Gardner timing error detector, a second order Phase-locked loop and a numerically controlled oscillator. The initial design uses floating-point precision. A fixed-point model is implemented using Xilinx System Generator and is used to generate a custom IP. Simulation is done by implementing a transceiver model with Simulink for the transmitter and parts of the receiver. The polyphase symbol timing synchronizer locks after about 4000 symbols for lower signal-to-noise and the Gardner timing error detector performs better than the zero-crossing error detector at higher signal-to-noise ratios.

The demands on heavy duty vehicles is constantly raising with government legislations on CO2 emissions becoming stricter and increasing customer demands. A continuous search for new methods and tools is a crucial element in finding more performance and lower emissions, which are prerequisites for heavy duty vehicles of the future. This thesis is conducted at Scania CV AB and aims at proposing a co-simulation setup which implements the engine management system, EMS, for turbocharger control, into engine simulation models that the company uses to simulate the behaviour of their combustion engines. The EMS software for turbocharger control is modelled in a MATLAB Simulink model and the engine simulation model is modelled in GT-SUITE. The thesis is also suggesting improvements to a turbine model that is modelled within the given EMS software. The results suggest a co-simulation setup that enables the engine simulation models to utilize the EMS software for turbocharger control which thereby enhances their ability to predict engine behaviour. The setup can also be used as a tool during the development process for other part of the EMS and could ease the need for physical engine tests in test cell. The suggested improvements to the turbine model revolves around building a model capturing the aspects of a so called twin scroll turbine and also to implement a better estimation of the turbine efficiency. The improvements to the turbine model ultimately leads to improving the response behaviour of the EMS turbocharger control system.

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In this thesis a Power-Hardware-in-the-Loop (PHiL) test rig is developed forhydro-pneumatic suspension by utilizing the physical suspension unit together with asimulated vehicle model in MATLAB Simulink. Power-Hardware-in-the-Loop is the termfor combining simulation models with power-transmitting hardware components inreal-time. This is useful when a system contains some parts that are complex and somethat are simpler to model. The simple parts of the system can be modelled andsimulated in conjunction with more complex parts consisting of physical objects. Thereason for keeping the items to be tested as physical components is their complexity andunknown characteristics that can be difficult to estimate. By utilizing PHiL, vehiclecomponents can be tested and developed without the need for the actual vehicle, whilekeeping the characteristics that the physical vehicle would bring. The process included development of a real-time enabled vehicle model, evaluation ofcontrol strategies as well as selection of hardware used for a small scale test rig. The project resulted in a functional small scale single wheel test rig. Validationexperiments confirmed that the rig produced results close to expectations. Thecommunication between the the test rig and the simulated model was accurate andshowed the potential for a full scale test rig. It can be concluded that a PHiL test rigcan be a suitable option to full vehicle testing. The vehicle model is fully customisable,so that the suspension units can be tested in various configurations of vehicles.