Maxime Debert

Optimal Energy Management Strategy including Battery Health through Thermal Management for Hybrid Vehicles

The paper proposes an energy management strategy (EMS) for hybrid electric vehicles (HEV) and plug-in hybrid electric vehicles (PHEV) taking into account battery health through an additional soft constraint on battery internal temperature, considered as one of the prime factors influencing battery aging. Battery cell temperature is modeled and considered as a second state constraint with the state of energy (SOE) in the optimization problem solved on-line using the equivalent consumption minimization strategy (ECMS). Simulation results are presented to highlight the contribution of the strategy including battery thermal management compared to the standard approach.

Implementation of comfort constraints in dynamic programming for hybrid vehicle energy management

Optimisation algorithms for hybrid vehicles are used to evaluate embedded strategies and component sizing. Using a quasi-static vehicle model, dynamic programming is commonly used to solve the optimal control problem. Using this type of numerical algorithm yields results that are often incompatible with the purpose of smoothness and driver acceptance. Introducing a comfort criterion in the cost function increases the problem complexity and, therefore, the computational burden. In this paper, a novel suboptimal method is proposed which yields valuable results in terms of performance and computational time. This approach takes occupant comfort into account and thus comes close to a realistic solution.

Energy Management of a High Efficiency Hybrid Electric Automatic Transmission

The energy management of a hybrid vehicle defines the vehicle power flow that minimizes fuel consumption and exhaust emissions. In a combined hybrid the complex architecture requires a multi-input control from the energy management. A classic optimal control obtained with dynamic programming shows that thanks to the high efficiency hybrid electric variable transmission, energy losses come mainly from the internal combustion engine. This paper therefore proposes a sub-optimal control based on the maximization of the engine efficiency that avoids multi-input control. This strategy achieves two aims: enhanced performances in terms of fuel economy and a reduction of computational time.