双向直流变换器作为综合能源系统中储能模块的关键接口设备，需要具备低电流纹波、高电压增益和宽范围软开关的特性。常规双向直流变换器在低压储能侧使用交错技术实现对电池友好的低电流纹波特性，然而受限于实际的生产工艺，这类交错型双向直流变换器存在多相电流不均衡问题。本研究基于耦合电感提出了一种无需复杂控制算法的电流自均衡双向直流变换器。在综合能源储能场景中，该变换器不但具有电流自均衡特性，还具备低电流纹波、高电压增益和宽范围软开关的综合优势。首先，该变换器利用钳位电容的安秒平衡特性，在一个开关周期内强制保持了交错电流的均衡，从而在电路拓扑层面即可实现电流自动均衡的低电流纹波特性。其次，作为储能电感的耦合电感兼顾了变压器功能，通过电路多级增益结构配合，实现了高电压增益特性。最后，本变换器使用了电压匹配控制和移相控制策略，对电压增益和功率大小方向进行解耦控制，保证了不同工作状态下的软开关特性。本研究分析了该变换器的工作原理与电路特性，并以此为基础设计了一款低压侧工作电压30 V至40 V、高压侧工作电压400 V、双向功率1 kW的实验样机。该样机模拟了低压侧锂电池在不同工作电压、功率大小和方向下的运行特性，从而有效验证了该拓扑的可行性。

As a key interface device of the energy storage module in the integrated energy system, the bidirectional DC converter needs the features of low current ripple, high voltage gain and wide range soft switching. To achieve battery-friendly low current ripple ability, bidirectional DC converters use interleaving technology on the low-voltage energy storage side. However, restricted by the actual production process, this type of interleaved bidirectional DC converter has multi-phase current imbalance problems. In this paper, a current self-balancing bidirectional DC converter without complex control algorithm was proposed based on coupled inductors. In the integrated energy storage scenario, the converter not only has the characteristics of current self-balancing, but also has the comprehensive advantages of low current ripple, high voltage gain and wide-range soft switching. First of all, the converter used the clamp capacitor ampere-second balance to forcefully maintain the interleaved current balance in one switching cycle. Hence the low current ripple characteristic of current self-balance was realized at the circuit topology level. Secondly, the coupled inductor is both an energy storage inductor and a transformer. Through the cooperation of the multi-stage gain structure of the circuit, the high voltage gain characteristic was realized. Finally, the converter used a voltage matching control and phase shifting control strategy to decouple the voltage gain and power direction and consequently soft switching characteristics were guaranteed under different working conditions. The article analyzed the working principle and circuit characteristics of the converter, and designed an experimental prototype with an operating voltage of 30 V to 40 V on the low-voltage side, 400 V on the high-voltage side, and a bidirectional power of 1 kW. The experimental prototype simulated the operating characteristics of the low-voltage side lithium battery under different operating voltages, power levels and directions, thus effectively verifying the feasibility of the topology.