Given the realities of today’s world, the goal of achieving vehicular fuel economy is of paramount importance. One cost effective solution to improve fuel economy without major modification of engines is using Active Fuel Management (AFM), which refers to on-demand cylinder activation and deactivation. One general characteristic of AFM engines is higher level of ignition force resulting in higher torque variation. Consequently the noise and vibration (N&V) performance of a vehicle with an AFM engine can reach an unacceptable level with aggressive cylinder deactivation. One solution to improve fuel economy without degrading N&V performance is the use of Active Engine Mount (AEM). This paper studies the control methods for active engine mount. Both open-loop and closed-loop control are developed based upon single-tone adaptive feed-forward control framework. The details of the algorithm are discussed and the stability and the robustness are examined. Integrated open-loop and closed-loop control is proposed to ensure fast response, enhance performance and robustness. A series of simulations are performed to demonstrate the control algorithm. It is shown that the integrated open-loop and closed-loop control algorithm yields the most promising results.
OPTIMIZATION OF A PASSENGER HYDRAULIC HYBRID VEHICLE TO IMPROVE FUEL ECONOMY
