IGBT芯片参数对瞬态均流特性的影响

IGBT模块一般采用多芯片并联的方式进行封装,但由于模块参数、驱动控制等差异,模块内部存在电流分布不均衡的问题。相比于稳态电流分布,瞬态电流分布的影响因素众多,是研究的热点。针对IGBT的芯片参数开展了模块内部各支路瞬态电流分布特性的研究。通过建立IGBT芯片模型及芯片并联的瞬态电路分析模型,计算单一芯片参数与多种芯片参数作用下IGBT模块的瞬态电流分布,提出新的适用于芯片支路瞬态均流分析的评价指标,得到了IGBT芯片参数对并联瞬态均流影响的规律。研究结果表明阈值电压、跨导和栅极电阻是对瞬态均流影响最大的3个芯片参数,且需要关注阈值电压与跨导的共同影响。研究结果对IGBT的芯片筛选及并联后的瞬态均流计算具有指导意义。

Influence of IGBT Chip Parameters on Transient Current Sharing Characteristics

IGBT modules are generally packaged with multiple chips in parallel.However,due to differences in module parameters,drive control and other factors,the current distribution in the module is imbalanced.Compared with the steady-state current distribution,the transient current distribution is affected by many factors,which is a hot research topic.Based on the IGBT chip parameters,the research on the transient current distribution characteristics of each branch inside the module was carried out.The transient current distribution of the IGBT module under the changes of a single chip parameter and multiple chip parameters was calculated by establishing the IGBT chip model and the transient circuit analysis model of the chip in parallel,a new evaluation index suitable for transient current sharing analysis of chip branches was proposed,and the law of the influence of IGBT chip parameters on parallel transient current sharing was obtained.The research results show that threshold voltage,transconductance and gate resistance are the three chip parameters that have the greatest impact on transient current sharing,and the combined effect of threshold voltage and transconductance should be given attention.The research results have guiding significance for the selection of IGBT chips and the calculation of transient current sharing after parallel connection.