Electric System for Efficient Hybridization of Off-Highway Vehicles

The electrification of off-highway vehicles is essential for reducing greenhouse gas emissions and improving energy efficiency. However, traditional approaches, like hydraulic load sensing circuits, suffer from low efficiency, while full electrification faces challenges due to the lower power density of electric machines compared to hydraulic counterparts. This paper introduces an electric power system for the hybrid hydraulic-electric architecture (HHEA) designed to overcome these challenges. A simulation modeling framework is developed to incorporate electric machines, drives, and battery, with a hydraulic power system utilizing multiple common pressure rails. The simulation results demonstrate the unique power flow conditions that improve machine efficiency and control strategies that can be implemented to improve performance of the system.