一种基于串联输入并联输出型LLC的噪声抑制磁集成方法

A Magnetic Integrated Method for Noise Suppression Based on Input Series Output Parallel LLC

提高工作频率有助于提高变换器的功率密度,促进变换器的小型化和轻量化发展,但是随之而来的电磁干扰(EMI)问题,影响了变换器的工作性能。为了在缓解噪声现象的前提下尽可能地实现变换器的高频化、小型化,该文基于串联输入并联输出(ISOP)型LLC拓扑,深入探究了共模噪声的来源和噪声的传导过程,进行了共模噪声的预测,解释了该拓扑抑制噪声的工作原理。在此基础上,详细分析了拓扑的磁集成特性,对变压器进行了磁集成设计,降低了磁心损耗。此外,对变压器的二次绕组进行了优化设计,充分利用了现有的绕组面积,进一步改善了高频效应带来的不良影响,有助于提高变换器的工作效率。采用电磁仿真软件搭建变压器的3D仿真模型,进行仿真对比分析。最后,搭建了一台样机,实验验证了所提磁集成设计方案和绕组优化设计方法的正确性和有效性。

The increasing the operating frequency is helpful to improve the power density of the converter, and promote the development of miniaturization and lightweight of converter. However,the EMI problem affects the performance of the converter. In order to realize the high frequency and miniaturization of the converter as much as possible under the premise of alleviating the noise phenomenon, based on the inputs series output parallel(ISOP) LLC topology, this paper deeply explores the source and transmission process of the common mode noise. The common noise is predicted which explains the working principle of the topology to suppress the noise. On this basis, the magnetic integration characteristics of the topology are analyzed in detail, and the magnetic integration design of the transformer is carried out to reduce the core loss. In addition, the secondary winding of the transformer is optimized to make full use of the existing winding area and further improve the high frequency effect of the transformer, which is helpful to improve the efficiency of the converter. The 3D electromagnetic simulation model of the transformer is built by using the electromagnetic simulation software, and the simulation and comparison is conducted. Finally, the experimental prototype is built,and the experimental result verifies the feasibility and effectiveness of the proposed transformer integrated method and the optimized design of secondary side winding.