A novel energy management strategy for hybrid electric vehicles using deep reinforcement incentive learning

Hybrid electric vehicles (HEVs) represent a significant step toward achieving fuel-efficient and environmentally friendly mobility. An effective energy management strategy (EMS) is needed to maximize the performance and energy efficiency of HEVs. However, since existing EMSs are generally developed utilizing rule-based or fixed structures, they often suffer from problems such as insufficient generalization capacity under variable driving conditions and exhibiting limited real-time applicability. Integrating deep reinforcement learning (DRL) algorithms into EMS design has attracted attention to overcome these limitations in recent years. DRL-based methods have a strong potential to develop more efficient and adaptive control strategies in HEVs. However, the proper design of reward functions representing multi-objective control goals and prioritizing the instantaneous objective remains a significant technical challenge, which can negatively affect the optimization performance during the learning process. We propose a deep reinforcement incentive learning (DRIL) algorithm to minimize fuel consumption and maintain battery charge sustainability under various driving conditions. To ignite the reinforcement learning agent to efficiently learn the optimal power distribution, we first propose an incentive reward function based on fuel consumption minimization and battery charge sustainability. Next, we introduce a novel soft actor-critic algorithm combined with incentive-based reward, forming the DRIL algorithm, which optimally balances exploration and exploitation for power allocation. Finally, the generalized advantage of the DRIL algorithm is evaluated through a human-in-the-loop (HIL) test-driving cycle, demonstrating its real-time applicability. The results of the experiments demonstrate that the proposed incentive mechanism can reduce fuel costs by 3.47%–3.04% compared to the existing DRL algorithms under the pre-training driving cycle and the HIL-obtained driving cycles, respectively.