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This paper constructed a parallel type hybrid-electric bus model based on GM-Allison system which is consisted of three planetary gear-sets and two motors. The simulation model is modified from the backward-looking simulation of ADVISOR. The hybrid-electric bus (HEB) is simulated to compare with a conventional diesel bus. Four different driving cycles are employed: Taipei City Bus Cycle, New York Bus Cycle, Manhattan Cycle, and Central Business District Cycle. Three different control strategies, namely speed control, torque control, and power control are studied. The simulation results show that the GM-Allison hybrid-electric bus with good control strategy can improve fuel economy by 66% compared to a conventional diesel bus. As for exhaust emissions, CO, HC, NOx and PM are reduced by 83%, 59%, 66% and 62%, respectively.

Butanol is deemed as a potential alternative fuel for vehicle, but there are few studies about applying butanol in engine combustion. This paper focuses on application of butanol-gasoline blend fuel on scooter engine. In this research, different volume percentage of butanol-gasoline blend fuel, B10, B20, B40, B60, B80 and B100 are applied on 125cc scooter engine to conduct engine experiment, and higher than B60 blend fuel is declared as high butanol concentration blend fuel. The test conditions are set at 4000 and 6000rpm under partial load and full load. After executing engine experiment, engine performance, brake specific fuel consumption (BSFC), emissions and combustion analysis are discussed. Furthermore, viscosity and fuel spray are tested with high butanol concentration blend fuel. The engine experimental result shows that B100 fuels can increase engine performance under engine 4000 and 6000rpm.

In order to improve the performance of a small gasoline engine, a part of oxygen is added to the intake air when the engine is operated at wide open throttle. The combustion process can be enhanced by using an oxidant that contains a higher proportion of oxygen than that in normal air. This paper studies the combustion characteristics and engine performance of such engine. Engine testing is performed on a 50 cc four-stroke spark-ignition engine with the oxygen concentration of intake air ranging from 21% to 25% by volume. The engine torque is increased with increasing oxygen concentration. The HC and CO emissions are decreased with oxygen enrichment, but the NOx emission is increased.

This study focuses on developing a cranking torque reduction strategy for a motorcycle with idling-stop system. At first, experiments are done to measure the electric current consumption of starting motor which is then converted into cranking torque by the motor torque constant. The experimental results also indicate that the piston position, after the engine is stopped, always remains at the bottom dead center of compression stroke. This will further increase the cranking torque for the next engine start due to static friction and compression pressure. This paper, therefore, proposes to retrofit the original generator of motorcycle as a motor/generator with the same operation power. The motor/generator could be worked in motor mode to assist the starting motor to crank the engine, and hence the instantaneous power provided by the starting motor could be reduced to extend its life time.

In this paper, the off-line analysis method is applied to develop three-way catalytic converter (TWC) diagnostic strategy including oxygen sensor (O2 sensor) diagnostic strategy with common narrow band oxygen sensor (EGO sensor) in Matlab/Simulink software. Moreover, Mototron ECU (Engine Control Unit) is used for monitoring catalyst deterioration. However, aged catalyst is difficult to possess so the different catalytic conversion efficiency (CCE) is simulated by using exhaust by-pass valve. The CEC (China Engine Corporation) 1L V2, four stroke, water-cooled engine is selected as target engine to conduct engine dynamometer test. After making sure O2 sensor operates normally, the catalyst diagnostic strategy test is executed. The experimental result shows that the catalyst deterioration accurately can be detected when the failure phenomenon takes place.