三端口直流变换器软开关分析的一种准确模型

目前大量文献对三端口直流变换器的软开关特性进行了相关研究,但大多是基于软开关的近似模型进行分析,分析结果存在较大的误差。首先介绍了基于端口之间单移相调制的变换器工作原理,并简化电路建立等效模型。此外,基于软开关原理建立包含全部谐波分量的软开关准确模型,借此模型分析软开关范围随电压增益和移相角的变化趋势。同时,根据数学模型和理论分析研究所有开关管在全负载范围内均可实现软开关的参数设计。最后,搭建仿真模型验证所提出理论结果的正确性。

Accurate Model for Soft-switching Analysis of Three-port DC-DC Converter

A large number of papers have studied the soft-switching characteristics of three-port isolated bidirectional converters, but most of them are based on the approximate model, so the analysis results have large errors. This paper introduces the working principle of the converter based on the single phase-shift control between ports firstly, and simplifies the circuit to build an equivalent model. In addition, based on the soft-switching principle, an accurate model of the soft-switch including all harmonic components is built, and the model is used to analyze the trend of the soft-switching range with voltage gain and phase-shift angle. At the same time, according to the mathematical model and theoretical analysis, the circuit parameters are designed so that all the switching can realize soft switching within the full range of loads. Finally, simulation model is built to verify the correctness of the proposed theoretical results.