Abstract:Under the “dual-carbon” strategy, the demand for efficient and low-emission bulk material handling equipment in the agricultural sector has been steadily increasing. Electric wheel loaders, owing to their environmental friendliness and energy efficiency, are gradually adopted in agricultural operations for material handling and field logistics. As the core energy-storage component of electric wheel loaders, the battery is subjected to large charge-discharge currents and frequent cycling under high-intensity and high-duty working conditions. These operating characteristics lead to accelerated battery degradation, reduced driving range, and increased operating costs. Targeting parallel electro-hydraulic hybrid (PEHH) wheel loaders, a coordinated optimization method for travel-speed planning and energy-management control was proposed, aiming to simultaneously mitigate battery aging and reduce overall energy consumption. Firstly, a mathematical model of the hybrid powertrain system and a battery lifetime prediction model were established. Subsequently, a coordinated optimization framework for travel speed and energy-management strategy was formulated, and the offline optimal solution was obtained by using a dynamic programming (DP) algorithm. Based on the structural characteristics and regularities observed in the offline optimal results, a rule-based online coordinated optimization strategy was developed to realize real-time travel-speed planning and electro-hydraulic power-split control. Simulation results demonstrated that the proposed online coordinated optimization algorithm achieved performance in battery life extension and energy consumption reduction that was close to the offline optimal benchmark.
