基于氮化镓的高频LLC变换器研究

Research on High Frequency LLC Converter Based on GaN

5G时代的到来对电源系统提出了更高的要求,即要求变换器具有高效率、高功率密度以及快速动态响应。针对该问题,使用第三代宽禁带半导体器件氮化镓(GaN)晶体管,优化变压器结构,采用新型分数匝结构,通过DSP数字控制方法设计一款400 V转12 V、输出功率为500 W的高效率、高功率密度LLC谐振变换器。通过理论分析高频状态下实际LLC电路参数影响,确定系统优化方向,并结合有限元仿真软件改进分数匝变压器结构,最后搭建实物平台验证理论的可行性。

The arrival of the 5G era has put forward higher requirements for the power system,that is,the converter is required to have high efficiency,high power density,and rapid dynamic response. In response to this problem,the third generation of wide bandgap semiconductor device gallium nitride(GaN)transistors was used. A new type of fractional turn structure was adopted to optimized transformer structure. The DSP digital control method was used to design a 400 V to 12 V,and the output power is 500 W high efficiency,high power density LLC resonance converter. Through theoretical analysis of the influence of actual LLC circuit parameters under high frequency conditions,the system optimization direction was determined,and the structure of fractional turns transformer was improved by combining finite element simulation software. Finally,a physical platform was built to verify the feasibility of the theory.