电动汽车混合储能装置三端口功率变换器设计

针对电动汽车混合储能装置功率分流问题，在三端口变换器拓扑结构基础上提出了能量型储能装置采用电流闭环、功率型储能装置采用电压闭环的控制系统。首先以双输入单输出模态建立该拓扑结构的状态空间模型，分析了功率电路的占空比-电感电流传递函数、占空比-输入电流传递函数和占空比-输出电压传递函数。其次设计了电压闭环控制器和电流闭环控制器，在保证母线电压稳定的前提下，可实现输出功率在功率型储能装置和能量型储能装置之间的精确分配。最后通过实验验证了控制系统在模拟HWFET工况和阶跃负载工况下的输入输出动态响应、电压控制精度和功率分流效果,其结果有利于实现混合储能装置功率精确分流。

Design of a Three-port Power Converter for Hybrid Energy Storage Device in An Electric Vehicle

Focused on the power splitting of the hybrid energy storage system in an electric vehicle, the current closed-loop control system and voltage closed-loop control system were adopted by the high specific energy storage and high specific power storage respectively based on a three-port converter. Firstly, the state space model of the power circuit was constructed based on Double-Input Single-Out, the duty cycle-inductor current transfer function, duty cycle-input current transfer function and duty cycle-output voltage transfer function were analyzed. Then the current closed-loop control system and voltage closed-loop control system were designed, and consequently the accuracy power splitting between the high specific energy storage and high specific power storage was achieved in the premise of DC bus voltage stabilization. Finally, bench experiments were conducted, and the input-output dynamic characteristic, control accuracy of voltage and power splitting performance of the proposed converter were validated under both simulated HWFET driving cycle and dynamic step load, which was effectively realized accurate power splitting of the hybrid energy storage system.