A nonisolated soft-switching bidirectional dc–dc converter (BDC) with interleaved technique and built-in transformer (BT) is proposed for the interface between the energy storage system and dc microgrid bus in this article. A T-type neutral-point-clamped circuit is integrated into an interleaved conventional buck–boost BDC to obtain a high voltage-gain ratio and decrease voltage stresses of power switches effectively. Compared with the couple-inductor, BT allows for a small magnetic core size, owing to its inherent saturation avoidance. The interleaved structure is employed to reduce the current ripple in the low-voltage side and helps to achieve voltage matching on both sides of the BT under pulsewidth modulation control. Thus, the circulating current can be lowered to improve efficiency. Phase-shift control is adopted to regulate the power flows of the proposed BT-BDC. Moreover, the optimal design is given for the component parameters to accomplish zero-voltage switching in a wide voltage range, which can reduce the switching losses. The operational principles and characteristics of the proposed BT-BDC are presented in detail. The analysis and performance have been fully validated experimentally on a 40–60 V/400 V 1-kW prototype. The accordance between the analysis and the experimental results further testifies the advantages.

中文翻译：

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一种具有高电压增益和全范围 ZVS 的新型交错式非隔离双向 DC-DC 转换器

本文提出了一种具有交错技术和内置变压器 (BT) 的非隔离软开关双向 DC-DC 转换器 (BDC) 用于储能系统和直流微电网总线之间的接口。将 T 型中性点钳位电路集成到交错式传统降压-升压 BDC 中，以获得高电压增益比并有效降低电源开关的电压应力。与耦合电感器相比，BT 允许使用较小的磁芯尺寸，这是由于其固有的饱和避免。交错结构用于降低低压侧的电流纹波，有助于在脉宽调制控制下实现BT两侧的电压匹配。因此，可以降低循环电流以提高效率。采用相移控制来调节所提出的 BT-BDC 的潮流。此外，对元件参数进行了优化设计，实现了宽电压范围内的零电压切换，降低了开关损耗。详细介绍了提议的 BT-BDC 的操作原理和特性。分析和性能已在 40–60 V/400 V 1-kW 原型上通过实验得到充分验证。分析与实验结果的一致性进一步证明了其优点。分析和性能已在 40–60 V/400 V 1-kW 原型上通过实验得到充分验证。分析与实验结果的一致性进一步证明了其优点。分析和性能已在 40–60 V/400 V 1-kW 原型上通过实验得到充分验证。分析与实验结果的一致性进一步证明了其优点。