电动汽车混合储能装置三端口功率变换器设计

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

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。

Aimed at the problem of power splitting in a hybrid energy storage device in an electric vehicle,a control system was proposed based on a three-port converter,in which the current closed-loop and voltage closed-loop were adopted by the high specific energy storage device and high specific power storage device,respectively.First,a state space model of this topology was constructed in double-input single-output mode,and the duty cycle-inductor current transfer function,duty cycle-input current transfer function and duty cycle-output voltage transfer function were analyzed.Then,the voltage closed-loop controller and current closed-loop controller were designed,and an accurate output power splitting between the high specific power storage device and high specific energy storage device was achieved in the premise of DC bus voltage stabilization.Finally,the input-output dynamic response,control accuracy of voltage and power splitting performance of the control system were validated under both simulated HWFET driving cycle and step load,indicating that an accurate power splitting of the hybrid energy storage device was realized.