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Fuel film dynamics in the intake manifold are considered to develop air fuel ratio (AFR) control strategy with on-line system identification for a V2 engine in this paper. A1000 cc four-stroke two-cylinder, water-cooled port injection SI engine is used as the target engine to develop the engine model in Matlab/Simulink. The model which consists of charging, fueling, combustion, friction, and engine rotational dynamics is used to verify the proposed AFR control. Since the fuel film dynamics changes with different engine operating conditions, the fuel film parameters are often listed as look-up tables for fuel film dynamics calculation in the conventional AFR control. However, those parameters might be inaccurate during transient engine operation. Different intake port temperature will affect the accuracy of those fuel film parameters as well. In order to solve this problem, recursive least square (RLS) is used to identify those parameters on-line.

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.

Range extender (RE), combined by an engine and a generator, charges the battery on the electric vehicle. Power management strategy of a range extended electric vehicle (REEV) will determine the required charging power according to battery state of charge (SOC) and driver demands. The charging power demand will be further converted into required operation torque and rotational speed demands from engine. Torque-based engine management system (EMS) is, therefore, required to receive the torque command from power management strategy for controlling the engine at required torque. This research develops a torque-based EMS for a RE engine which is a 125cc four-stroke semi-direct injection engine and fueled by liquefied petroleum gas (LPG). The RE engine is operated to provide stable power output for driving generator, so we only select two operating points for this engine. The first operating point is for higher power output and better fuel economy.