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Commercially available Hybrid Electric Vehicles (HEVs) have been around for more than ten years. However, their market share remains small. Focusing only on the improvement of fuel economy, the design tends to reduce the size of the internal combustion engine in the HEV, and uses the electrical drive to compensate for the power gap between the load demand and the engine capacity. Unfortunately, the low power density and the high cost of the combined electric motor drive and battery packs dictate that the HEV has either worse performance or much higher price than the conventional vehicle. In this research, a new design philosophy for parallel HEV is proposed, which uses a full size engine to guarantee the vehicle performance at least as good as the conventional vehicle, and hybridizes with an electrical drive in parallel to improve the fuel economy and performance beyond the conventional cars. By analyzing the HEV fuel economy versus the increasing of the electrical drive power on typical driving conditions, the optimal hybridization electric power capacity is determined. Thus, the full size engine HEV shows significant improvement in fuel economy and performance, with relatively short cost recovery period. A new control strategy, which optimizes the fuel economy of parallel configured charge sustained hybrid electric vehicles, is proposed in the second part of this dissertation. This new approach is a constrained engine on-off strategy, which has been developed from the two extreme control strategies of maximum SOC and engine on-off, by taking their advantages and overcoming their disadvantages. A system optimization program using dynamic programming algorithm has been developed to calibrate the control parameters used in the developed control strategy, so that the control performance can be as close to the optimal solution as possible. In order to determine the sensitivity of the new control strategy to different driving conditions, a passenger car is simulated on different driving cycles. The performances of the vehicle with the new control strategy are compared with the optimal solution obtained on each driving condition with the dynamic programming optimization. The simulation result shows that the new control strategy always keeps its performance close to the optimal one, as the driving condition changes.

The fuel economy of Fuel Cell Vehicles (FCVs) is affected by various factors such as the fuel cell efficiency, the regenerative energy capturing, the power control strategy, the vehicle driving patterns, the degree of hybridization between fuel cells and energy storage systems, and so on. In this thesis, a new power control strategy is proposed to improve fuel economy for hybrid FCVs considering the fuel cell efficiency and battery energy management. In order to show the power flows due to the proposed power control strategy and analyze the fuel economy, an overall vehicle simulation for three types of FCVs is implemented. The results show that the fuel economy can be improved by operating the fuel cell system within the specified high efficiency region and managing the state of charge (SOC) of the battery for absorbing regeneration energy effectively.

The Subject of this work is the optimization of the control stratgy for a Plug-In Range Extender in order to decrease CO2 emissions with respect to the regulations. Therefore, the vehicle is equipped with a gasoline combustion engine, a high voltage battery and two electric motors. One electric motor propells the front axle and the other one is connected to the combustion engine to generate electric power. The control is restricted by customer requirements due to the concept of the vehicle. A Model-in-the-Loop is created to simulate the control strategy with support of a battery model. Therefore, the control strategy is optimized in a Matlab/Simulink environment. The simulation results are compared to tests on the dynamometer rig. The optimization highly depends on the specific goal function, which can be a global optimization or a local minimum to balance the State of Charge. Furthermore, customer related drive cycles are taken into account to analyze the control strategy. / Master of Science

In recent years there has been a growing interest in moving away from large centralized power generation toward distributed energy resources. Solar energy generation presents several benefits for use as a distributed energy resource, especially as a peaking power source. One drawback of solar energy sources is the need for energy storage for the system to be utilized for a significant percentage of the day. One way of avoiding adding energy storage to a solar generation system while still maintaining high system utilization is to design the power conversion subsystem to also provide harmonic and reactive compensation. When the sun is unavailable for generation, the system hardware can still be utilized to correct for harmonic and reactive currents on the distribution system. This system's dual-purpose operation solves both the power generation need, and helps to improve the growing problem of harmonic and reactive pollution of the distribution system. A control method is proposed for a system that provides approximately 1 kW of solar generation as well as up to 10 kVA of harmonic and reactive compensation simultaneously. The current control for the active was implemented with the synchronous reference frame method. The system and controller was designed and simulated. The harmonic and reactive compensation part of the system was built and tested experimentally. Due to the delay inherent in the control system from the sensors, calculation time, and power stage dynamics, the system was unable to correct for higher order harmonics. To allow the system to correct for all of the harmonics of concern, a hybrid passive - active approach was investigated by placing a set of inductors in series with the AC side of the load. A procedure was developed for properly sizing the inductors based on the harmonic residuals with the compensator in operation. / Master of Science

Hardware-in-a-loop (HIL) testing and simulation for components and control strategies can reduce both time and cost of development. HIL testing focuses on one component or control system rather than the entire vehicle. The rest of the system is simulated by computer systems which use real time data acquisition systems to read outputs and respond like the systems in the actual vehicle would respond. The hardware for the system is on a scaled-down level to save both time and money during testing. The system designed to simulate the REVLSE Equinox split parallel hybrid consists of five direct current (DC) permanent magnet motors. These motors are used in the system to test the controller software of the vehicle. Two of the motors act as power plants simulating the spark ignited Ethanol engine and the rear traction motor. These two motors are controlled by DC variable speed controllers. The other motors are used as generators to simulate the load from the belted alternator starter (BAS) and the road load on each axle. The motors on each axle are joined together mechanically using a belt and pulley system. The front and rear axle of the system are not connected to simulate the actual vehicle where the power plants are gear-reduced before they make contact with the road and therefore do not actually spin at the same speeds. The computer software and hardware used to run the HIL hybrid system is National Instruments LabView and CompactRIO. LabView provides an easy interface through which programs for the RIO can be written. The RIO gives the user the ability to measure the power into and out of different components in the system to measure the efficiency of the system. The ability to measure system efficiencies using different powertrain inputs and loading schemes is what makes the HIL system a valuable tool in control modeling for the Equinox. LabView and the RIO allow the user to optimize the control strategy with the two power plant inputs and the BAS to make sure the high voltage system stays charged and improve the overall efficiency of the vehicle without the actual vehicle. The HIL system allows other work to be done of the vehicle during the control development. During a constant axle speed test at 730 RPM with constant generator resistance, the front engine efficiency was 33.8%, the BAS efficiency was 53.0%, the rear load generator efficiency was 51.2% and the overall efficiency of the front axle was 24.0%. These results show that the system can simulate the powertrain of a hybrid vehicle and help create and validate a control scheme. / Master of Science

In this project, the wave energy converter (WEC) designed at Seabased AB and Uppsala University was modelled in the program MATLAB. In order to increase the average output power, the WEC should be controlled. Therefore, the simulation tool was used to investigate damping strategies where the damping coefficient was changed at different times of the wave period. The tests showed that a suitable damping strategy, matched to the sea state at the specific location of the site and the overall WEC design, increases the average output power, as well as may protect the WEC from damages. This can lead to a more sustainable WEC system, which may contribute to the increasing demand of renewable energy solutions.

As world transport has grown in complexity, so has public pressure for safe flight. The scheduled airline industry has a consistently good safety record. Unfortunately, the business jet industry has not kept pace with the airline safety statistics and lags far behind. During safety surveys and reports over the past 5 years there has been increasing comment and concern over the perceived safety standards of business jets operations compared with normal scheduled airline services. The UK Civil Aviation Authority (CAA) has reported that based on flight hours flown, the fatal accident rate for smaller jet aircraft below 15 tonnes was twice that for large passenger aircraft (CAA 2006a). The CAA also identified that the majority of the accidents occur during the approach and landing phase of the flight. There is however, a lack of research concerning business jet operations. Due to the unique and varied style of operations, business jet flights have many factors that differentiate it from normal scheduled airline operations. Business jet accidents have been reported but they have not been further investigated for any overall causes. The study described in this thesis, a Grounded Theory analysis of accident data was conducted to develop a model of the factors that contributed to the accidents. The model that was developed demonstrated that Pilot skills, Command and Crew Resource management are the key central elements, with the ground organisations such as engineering and ground operations personnel as a contributory influence. As piloting skills were determined as a key factor in the accident statistics and the accident model, a simulator trial was also conducted to assess the manual flying skill levels of business jet pilots. The trial was both a challenging manual flying task and a profile that is included as part of the Pilot Skill test prior to the issue of a commercial pilot’s licence. The simulator trial confirmed that although all the pilots were correctly tested and certified commercial pilots, a significant proportion did not fly an accurate airspeed on approach within the CAA examination tolerances. The simulator trial data and the grounded theory model found that there are concerns for the piloting skills of business jet pilots in their ability to fly an accurate airspeed on approach. The results from this investigation yield findings concerning the piloting skill and accuracy of the business jet pilots that had not previously been identified. The results also emphasise the need to include adequate testing and supervision during business jet operations. It is recommended that further research be conducted to evaluate actual piloting skill and accuracy during the licence skill test.

The purpose of this study was to compare the shoulder resultant joint moment (RJM) during a shoulder internal rotator exercise using elastic resistance employing four different movement strategies and two different starting elastic strains. Methods: Ten subjects aged 27.4 ± 2.6 yr (5 female and 5 male) with no previous shoulder pathology performed four sets of six repetitions of shoulder rotation though 180° using elastic resistance (Thera-Band® elastic band, blue) during two acceleration (medium and low) and two cadence (2s:2s, <1s:1s) strategies at 0% elastic starting strain. The acceleration movement strategies were also performed with starting strain of 30%. A mathematical model using Newtonian mechanics was used to compute the RJM. Elastic band recoil force was measured with a force transducer. Forearm acceleration was determined by a miniature uniaxial accelerometer secured at the wrist. Electrogoniometer data were collected to determine the range of motion (ROM) as well as the angle between the forearm and band which was used to determine elastic moment arm. Paired t-tests were used to identify joint angle specific RJM differences between conditions. Results: Angle specific comparisons revealed that RJM in the moderate acceleration movement strategy was significantly different from RJM in the low acceleration movement strategy through 150° (83%) of range of motion (p<0.05). Shoulder RJM was up to 111% higher in the moderate acceleration strategy (P < 0.01). Angle specific comparisons revealed RJM in the <1:1 cadence strategy was significantly different from RJM in the 2:2 cadence through 108° (60%) of the range of motion (p<0.05). RJM was up to 47% higher in the <1:1 cadence (p<0.01). RJM in the low acceleration strategy was significantly greater with 30% elastic start strain relative to 0% elastic start strain through 180º of angular excursion (p<0.001). The pattern and magnitude of neuromuscular loading was significantly different in higher acceleration movement strategies (moderate acceleration and fast cadence). Conclusions: These findings indicate that differential limb acceleration as a result of movement strategy significantly affects shoulder load during elastic resistance exercise. The pattern and magnitude of load was different in each movement strategy and could result in differential neuromuscular adaptation through training. Clinicians and exercise professionals should consider movement strategy/acceleration as an important factor when prescribing elastic resistance exercise for safety and efficacy. / October 2006

The purpose of this study was to compare the shoulder resultant joint moment (RJM) during a shoulder internal rotator exercise using elastic resistance employing four different movement strategies and two different starting elastic strains. Methods: Ten subjects aged 27.4 ± 2.6 yr (5 female and 5 male) with no previous shoulder pathology performed four sets of six repetitions of shoulder rotation though 180° using elastic resistance (Thera-Band® elastic band, blue) during two acceleration (medium and low) and two cadence (2s:2s, <1s:1s) strategies at 0% elastic starting strain. The acceleration movement strategies were also performed with starting strain of 30%. A mathematical model using Newtonian mechanics was used to compute the RJM. Elastic band recoil force was measured with a force transducer. Forearm acceleration was determined by a miniature uniaxial accelerometer secured at the wrist. Electrogoniometer data were collected to determine the range of motion (ROM) as well as the angle between the forearm and band which was used to determine elastic moment arm. Paired t-tests were used to identify joint angle specific RJM differences between conditions. Results: Angle specific comparisons revealed that RJM in the moderate acceleration movement strategy was significantly different from RJM in the low acceleration movement strategy through 150° (83%) of range of motion (p<0.05). Shoulder RJM was up to 111% higher in the moderate acceleration strategy (P < 0.01). Angle specific comparisons revealed RJM in the <1:1 cadence strategy was significantly different from RJM in the 2:2 cadence through 108° (60%) of the range of motion (p<0.05). RJM was up to 47% higher in the <1:1 cadence (p<0.01). RJM in the low acceleration strategy was significantly greater with 30% elastic start strain relative to 0% elastic start strain through 180º of angular excursion (p<0.001). The pattern and magnitude of neuromuscular loading was significantly different in higher acceleration movement strategies (moderate acceleration and fast cadence). Conclusions: These findings indicate that differential limb acceleration as a result of movement strategy significantly affects shoulder load during elastic resistance exercise. The pattern and magnitude of load was different in each movement strategy and could result in differential neuromuscular adaptation through training. Clinicians and exercise professionals should consider movement strategy/acceleration as an important factor when prescribing elastic resistance exercise for safety and efficacy.