Compensation of mechanical inertia in car power transmission systems

In order to secure energetic efficiency the combustion engine should operate with relatively high torque level. In the circumstances of small power demand; for instance, when the car is moving with low speed it is associated with low rotational speed of engine. In power transmission systems with constant power supply e.g. CVTs characterised by a large differentiation of kinematic transmission, the investigated issue plays an important role. In order to secure a prompt response of such transmission systems a variety of control strategies is proposed. Particular attention is devoted to transmission systems with zero inertia, which apply an supplementary power source (device applying inertia or electrical motor) to assist the engine in accelerating in the transition phase. Due to the large complexity of those systems an alternative construction is proposed, one which does not apply a hybrid drive. The compensation of mechanical inertia secured by a short-term engine supercharging. This supercharging is performed with the aid of compressed air chamber. This paper presents the design and control of this system and the technique of controlling it. On the basis of results of stand tests it was indicated among all that an abrupt temperature fall resultsin from iar expansion is effective in preventing knocking sounds in combustion.