基于高压SiC MOSFET的高效谐振全桥变换器研究

Research on High Efficient Resonant Full-bridge Converter with High Voltage SiC MOSFET

对谐振全桥变换器而言,利用SiC MOSFET能提高开关频率,达到增大功率密度、降低系统成本、提高效率及简化拓扑电路的目的。文章研究了一种基于第三代SiC MOSFET的零电压(ZVS)LLC谐振全桥DC/DC变换器,利用Cree公司1 000 V/65 mΩ高压SiC MOSFET设计出高频、高功率密度20 k W ZVS LLC谐振隔离全桥变换器并进行了样机研制。实验结果表明,该变换器的开关频率范围扩大到180 k Hz至400 k Hz,最高效率可达到98.4%。该方案能广泛应用于高压直流电源、感应加热、电动汽车充电等三相隔离新能源领域。

With SiC MOSFET, resonant converter can achieve high frequency and high efficiency, thus increasing the power density with reducing total cost and simplify topology. It designed a zero voltage switching（ZVS） soft switching converter with the 3rd generation（Gen3） Silicon Carbide（SiC） MOSFET. High voltage SiC MOSFET（1 000 V/65 mΩ） from Cree were used in the design of a 20 k W high frequency high power density ZVS LLC resonant full bridge DC/DC converter. A prototype of this converter with high modulated switching frequency range from 180 k Hz to 400 k Hz was developed to demonstrate how the SiC MOSFET can help achieve the highest performance for a soft switching DC/DC converter with the maximum efficiency measured at 98.4%. These converters can be commonly used in isolated three-phase renewable applications such as high voltage DC（HVDC） system, inductive heating, or electric vehicle（EV） charger.