An Improvement of Rule-Based Control Strategy for a Series Hydraulic Hybrid Vehicle

Abstract

In a hybrid hydraulic vehicle, the hydraulic accumulator is used as the secondary power source in addition to the engine to propel the vehicle. Because of the low energy density characteristic, the accumulator can only afford the required power in a short period. After that the engine mush be involved. Published works provide evidences that the hydraulic hybrid vehicle is suitable for vehicles working under start-stop-and-go driving patterns. This paper present three rule-based control schemes for a 3.5- ton series hydraulic hybrid truck. The simulation results indicate that by applying suitable control scheme, the proposed series hydraulic hybrid system might offer better fuel economy improvements for both urban and highway driving condition.