SiC/Si混合开关时间延迟及其信号调制方法  

Analysis of SiC/Si HyS Loss Characteristics and Its Driving Signal Modulation Circuit

作　　者：丁四宝 王盼宝[1] 王卫[1] 徐殿国[1] Ding Sibao;Wang Panbao;Wang Wei;Xu Dianguo(School of Electrical Engineering&Automation Harbin Institute of Technology,Harbin 150001 China)

机构地区：[1]哈尔滨工业大学电气工程及自动化学院,哈尔滨150001

出　　处：《电工技术学报》2025年第4期1129-1144,共16页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(52377173)。

摘　　要：SiC MOSFET和Si IGBT并联构成的混合开关(SiC/Si HyS)结构是一种优化效率和成本的综合解决方案。依靠SiC MOSFET的低导通时间构建Si IGBT的零电压开通和关断,并继承Si IGBT在高负载电流下的低导通损耗特性,从而提升系统整体效率。为了更简单高效地生成SiC/Si HyS的SiC MOSFET和Si IGBT驱动信号,该文提出一种针对最小SiC导通模式的信号调制电路,通过配置对应的RC缓冲电路中的电阻、电容值即可调节控制模式中的四个时间尺度,该方法具有灵活简单等优点。首先,理论分析最小SiC导通模式下的SiC/Si HyS结构损耗分布特性;其次,给出信号调制电路原理并介绍信号调制电路的工作原理,建立RC缓冲电路参数和时间尺度之间的函数方程;最后,基于搭建的SiC/Si HyS硬件平台,在双脉冲测试电路中验证最小SiC导通模式下的SiC/Si HyS损耗特性和所提信号调制电路的有效性,并在1.5 kW两电平逆变器中检验所提信号调制电路的动态运行特性。Silicon carbide(SiC)metal-oxide-semiconductor field effect transistors(MOSFETs)are increasingly preferred over Silicon(Si)insulated-gate bipolar transistors(IGBTs)due to their superior switching capabilities and high temperature withstand.Nonetheless,Si IGBTs maintain their position as the primary power devices in industrial settings,attributed to their greater durability and reduced on-resistance when dealing with high currents.However,the limited switching frequency of IGBTs impedes the advancement of power electronic converters,as the lingering currents during the off-transition phase lead to elevated switching losses.A hybrid SiC/Si switch(HyS)offers a balanced solution,optimizing cost and switching performance.Typical SiC/Si HyS control methods involve deactivating Si IGBTs sooner and reactivating them after SiC MOSFETs.The minimum conduction strategy for SiC MOSFETs within the SiC/Si HyS configuration ensures that SiC MOSFETs operate exclusively during the Si IGBTs’switching intervals,which contributes to minimizing the expenses associated with SiC MOSFETs and the required chip space.Since SiC MOSFET is activated twice during the switching transients of Si IGBT,the minimum SiC MOSFET conduction mode has two more controllable time scales than the common mode of SiC/Si HyS.By dissecting each sub-stage,the loss characteristics of the minimum SiC conduction mode are quantitatively analyzed.A visual relationship regarding the time scale and load current on the conduction loss is provided in a two-level sinusoidal inverter.At low-current conditions,the output characteristic of the Si IGBT is nonlinear,resulting in increased time scales that help to reduce the conduction loss.A signal modulation circuit is proposed to conveniently generate the control signal for the minimum SiC MOSFET conduction HyS.The proposed circuit comprises one OR gate(Q4)and three D flip-flops(Q1~Q3).The time delay is generated by adjusting the input signal rate with the RC buffer circuit.The rising edge of sO_on and sO_off generates the

关 键 词：SiC MOSFET Si IGBT 混合开关 开关损耗 信号调制 

分 类 号：TM92[电气工程—电力电子与电力传动]