This work presents a new type of high-order LCLCL resonant DC/DC converter. The converter in this study can properly inject the third harmonic for energy transmission through optimal configuration and parameter design of the resonant tank, which can not only achieve a wider voltage regulation range but also provide an easy method for soft start and overcurrent protection. In this study, both switches can realise soft switching, and due to the injection of the third harmonic, the loss of the secondary rectifier diode is reduced. This article describes the working principle of the LCLCL converter and provides the parameter design principle and small-signal modelling method. In the laboratory, a 400 W prototype with 400 V input and 24 V output is built to verify the correctness of the theoretical analysis.

中文翻译：

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基于谐波优化的高阶高性能LCLCL DC / DC转换器

这项工作提出了一种新型的高阶LCLCL谐振DC / DC转换器。通过优化谐振腔的配置和参数设计，本研究中的转换器可以适当地注入三次谐波以进行能量传输，这不仅可以实现较宽的电压调节范围，而且还为软启动和过流保护提供了简便的方法。在这项研究中，两个开关都可以实现软开关，并且由于注入了三次谐波，次级整流二极管的损耗得以降低。本文介绍了LCLCL转换器的工作原理，并提供了参数设计原理和小信号建模方法。在实验室中，构建了具有400 V输入和24 V输出的400 W原型，以验证理论分析的正确性。