The Impact of Dynamic Deceleration Limit on Optimal Speed Planning for Fuel Cell Hybrid Electric Vehicles

Speed profiles and energy management strategy (EMS) significantly influence the energy efficiency of fuel cell hybrid electric vehicles (FCHEVs). Sequential optimization of speed planning and EMS in two layers could be beneficial over co-optimization in terms of computational burden and speed. Traditionally, speed planning is constrained by the electric motor’s capabilities, alongside minimum deceleration rates, to ensure safe and realistic vehicle maneuvers. However, these constraints typically overlook the battery and power electronics’ capacity to store regenerative power, with power allocation issues being addressed only in the subsequent layer. In response, a new dynamic deceleration rate that incorporates the regenerative capacity limits directly into the speed planning layer has been introduced in this study. The energy efficiency of optimal speed profiles generated using this novel approach is compared with conventional speed profiles under winter conditions, demonstrating enhanced performance and energy recovery.