This paper focuses on aviation energy conservation and emission reduction as primary objectives for hybrid electric propulsion aircraft. By summarizing current research in these areas, it provides an overview of key technologies related to hybrid electric propulsion system’s energy management. Initially, the study designs the system operation modes based on the operational conditions of large-load hybrid electric propulsion aircraft and establishes an energy change model for each mode. Subsequently, it conducts a thorough transient management of the energy converters, including engines, generators, batteries, and motors--within the hybrid system, while designing an energy control law aimed at energy savings and emission reductions. Next, the paper introduces a hybrid power system energy management strategy that utilizes reinforcement learning to optimize the distribution of engine and motor torque, thereby enhancing energy utilization and fuel economy. Finally, a hardware-in-the-loop verification system is designed for the energy management strategy to experimentally validate the research findings. The findings of this research can offer foundational design concepts and analytical methods for the design and energy management of hybrid electric propulsion systems.
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