Dry Type Engine Clutch Control for a Parallel HEV at Launch Start Condition
A parallel type HEV has a power transfer device that is constructed by clutches and the device which is located between engine flywheel and electric traction motor is called 'Engine Clutch' When a traction motor of could not generate power to move, the HEV must launch only by engine power. In this situation the slip speed control and transmitted torque control are very important. In this study control strategies of dry type engine clutch is proposed to satisfy desired clutch engagement time and required torque at launch start condition. A dynamic model of a parallel type HEV driveline is constructed to apply the method proposed.
Model Reference Adaptive Control during Mode Transition of a Parallel Hybrid Electric Vehicle
Model reference adaptive control (MRAC) is proposed for torque coordination in order to improve dynamic performance during the mode transition of a parallel hybrid electric vehicle. Although model reference control (MRC) has been shown to be effective in controlling the mode transition, difficulties arise in application because the parameters of the reference model is unknown and time-varying. Small error of the parameter estimation may lead to instability of the MRAC system. With a reference model whose parameters are tuned by an estimator, the stability condition of the MRAC is derived. Thereafter, an adaptive law is designed to tune the feed-forward and feedback gains to satisfy the stability conditions for the mode transition. Simulation results show that the proposed MRAC can be stable even when the estimation error is large, and performs well under different road conditions.
Accurate measurements of output characteristics and detonations of motorbike high-speed racing engine and their optimization at actual atmospheric conditions and combusted mixture composition
Abstract At a motorbike high speed racing engine there is very important an output engine characteristics which depends significantly on a detonation combustion rate, atmospheric conditions and a combusted mixture composition. The combustion process has got a relevant influence on a wear degree of main engine parts or on their damage eventually. The detonation combustion rate is very important because this kind of burning can be not only destructive but a useful phenomenon, as well. If the process of detonation burning is kept on a certain level, it can help significantly to the next increasing of an engine power output. In this article there is described the measurements of output characteristics of a high-speed racing engine which were performed by means of a data-recording system and the detonation combustion was evaluated using a quantitative method. The actual values of atmospheric conditions and the mixture composition were added to the measured values. Then the obtained values are compared visually with a damage degree of an engine piston caused by the detonation burning. The result is a limit value expressed in a number of detonation units related to a run distance interval of the vehicle driven by the high-speed racing engine. In framework of this run distance interval there is the process of detonation burning profitable. As well as it increases an engine power output and together it is not destructive with regard to engine design parts.