一种单输入双输出高增益DC-DC变换器

A single input dual output high step-up DC-DC converter

随着分布式发电在中低压场合的应用越来越广泛,对高增益直流变换器的需求日益增加。提出一种新型单输入双输出高增益DC-DC变换器。该变换器在传统Boost电路基础上引入电容和二极管组成极性反向极,功率端口通过差分连接方式互联,提高了变换器电压增益,降低了开关管电压应力;同时端口功率控制彼此独立,进一步提高了电能路由的灵活性。详细分析了该变换器的电路结构和工作原理,推导出稳态特性下的电压增益、主要开关器件电气应力以及电流纹波等表达式。在此基础上,提出了基于矢量时间作用的模型预测控制策略,建立了该变换器预测模型、推导出开关管矢量时间以及设计了目标函数寻优过程。最后,通过仿真和实验验证了所提变换器及其控制策略不仅可行、有效,而且具有高运行效率与低电压应力。

Distributed generation(DG)has been widely used in low and medium-voltage applications.The need for high step-up DC-DC converters continues to increase.A novel single input dual output(SIMO)high step-up DC-DC converter is proposed.This converter adds a capacitor and diode to form a polarity reverse pole based on the traditional Boost circuit,and the power ports are interconnected through differential connection,improving the voltage gain of the converter and reducing the voltage stress of the switch.At the same time,port power control is independent,further improving the flexibility of power routing.The circuit structure and working principle of the converter are analyzed in detail,and expressions for voltage gain,electrical stress of main switching devices,and current ripple in steady-state are derived.Then,a vector-based time model predictive control strategy is proposed,a predictive model of the converter is established,the vector time of the switch is derived,and the optimization process of the objective function is designed.Finally,the feasibility of the proposed converter and the effectiveness of the control strategy are verified through simulation and experiment.The higher efficiency and lower voltage stress of semiconductors are also verified.