*Article* **Predictive Energy Management Strategy for Hybrid Electric Air-Ground Vehicle Considering Battery Thermal Dynamics**

**Zhe Li 1,2, Xiaohong Jiao 1, Mingjun Zha 2, Chao Yang 2,\* and Liuquan Yang <sup>2</sup>**

<sup>1</sup> Electrical Engineering, Yanshan University, Qinhuangdao 066004, China

<sup>2</sup> School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China

**\*** Correspondence: cyang@bit.edu.cn

**Abstract:** Hybrid electric air-ground vehicles (HEAGVs), which can run on the land and fly in the air, are considered a promising future transportation. The operation of HEAGVs, accompanied by high energy consumption, could lead to increasing battery temperature, which may affect the lifespan of the battery. To make the battery last longer and improve energy efficiency, an effective energy management strategy (EMS) is necessary for the operation of HEAGVs. In this regard, this paper proposes a predictive EMS based on model predictive control (MPC). Firstly, speed information is obtained by intelligent network technology to achieve a prediction of power demand, and then the state of charge (SOC) reference trajectory is planned. Secondly, a Pontryagin's minimum principle-based model predictive control (PMP-MPC) framework is proposed, including battery thermal dynamics. Under the framework, fuel efficiency is improved by reducing the temperature of the battery. Finally, the proposed method is compared to PMP, dynamic programming (DP), and rule-based (RB) methods. The effect of different preview horizon sizes on fuel economy and battery temperature is analyzed. Verification results under two driving cycles indicate that compared with the rule-based method, the proposed method improves fuel economy by 5.14% and 5.2% and decreases the temperature by 5.9% and 4.9%, respectively. The results demonstrate that the proposed PMP-MPC method can effectively improve fuel economy and reduce temperature.

**Keywords:** hybrid electric air-ground vehicle; energy management strategy; battery temperature; model predictive control; Pontryagin's minimum principle
