This paper proposes a novel nonisolated single-input dual-output three-level dc-dc converter (SIDO-TLC) appropriate for medium- and high-voltage applications. The SIDO-TLC is an integration of the three-level buck and boost converters, whose output voltages are regulated simultaneously. Reducing voltage stress across semiconductor devices, improving efficiency, and reducing inductors size are among the main merits of the new topology. Moreover, due to the considerably reduced volume of the step-down filter capacitor, a small film capacitor can be used instead, whose advantages are lower equivalent series resistance and a longer lifespan. A closed-loop control system has been designed based on a small-signal model derivation in order to regulate the output voltages along with the capacitors' voltage balancing. In order to verify the theoretical and simulation results, a 300-W prototype was built and experimented. The results prove the aforementioned advantages of the SIDO-TLC, and the high effectiveness of the balancing control strategy. Furthermore, the converter shows very good stability, even under simultaneous step changes of the loads and input voltage.

中文翻译：

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一种新型单输入双输出三电平DC__C变换器


本文提出了一种适用于中压和高压应用的新型非隔离单输入双输出三电平 DC-DC 转换器 (SIDO-TLC)。 SIDO-TLC 是三电平降压和升压转换器的集成，其输出电压同时调节。降低半导体器件的电压应力、提高效率和减小电感器尺寸是新拓扑的主要优点。而且，由于降压滤波电容的体积大大减小，可以用小型薄膜电容代替，其优点是等效串联电阻更低，寿命更长。基于小信号模型推导设计了闭环控制系统，以调节输出电压以及电容器的电压平衡。为了验证理论和仿真结果，搭建了300W原型机并进行了实验。结果证明了SIDO-TLC的上述优点以及平衡控制策略的高效性。此外，即使在负载和输入电压同时阶跃变化的情况下，转换器也表现出非常好的稳定性。