重庆大学 输变电装备技术全国重点实验室
State Key Laboratory of Power Transmission Equipment Technology, Chongqing University, Chongqing 400044, P. R. China
碳化硅金属-氧化物-半导体场效应晶体管（Metal-Oxide-Semiconductor Field-Effect Transistor，MOSFET）的阈值电压分散漂移严重影响了其在应用中的可靠性。特斯拉Model3召回事件中表明“后电机逆变器功率半导体元件”可能存在“微小的制造差异”，部分车辆使用“一段时间后”元件制造差异可能会导致后逆变器发生故障，造成逆变器不能正常控制电流。文中针对该召回事件从器件本体和电路回路参数差异两个方面展开系统性研究，器件的本体差异可能会导致阈值电压分散性随着应力时间的延长而增大，进而使分流恶化，电路中驱动回路和主回路的寄生电感差异也会导致分流恶化。研究表明，器件本体和电路回路参数差异都能通过对阈值漂移分散性的影响引起分流恶化，进而导致系统故障。
The dispersive threshold voltage drift in silicon carbide metal-oxide-semiconductor field-effect transistors (MOSFETs) severely impacts their reliability in applications. The Tesla Model 3 recall incident highlighted that the "rear motor inverter power semiconductor components" might have "minor manufacturing variations," which could lead to inverter failure over time, resulting in the inverter"s inability to control current properly. This paper conducts a systematic study on the recall event from two perspectives: device intrinsic differences and circuit loop parameter variations. The intrinsic differences in devices may cause the threshold voltage dispersion to increase with prolonged stress time, thereby exacerbating current sharing issues. Additionally, variations in parasitic inductance in the drive and main circuits can also worsen current sharing. The research demonstrates that both device intrinsic differences and circuit loop parameter variations can influence the threshold voltage drift dispersion, leading to deteriorated current sharing and ultimately causing system failures.
