Comparative electrothermal analysis between SiC Schottky and silicon PiN diodes: Paralleling and thermal considerations
Comparative electrothermal analysis between SiC Schottky and silicon PiN diodes: Paralleling and thermal considerations
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DOI：
10.1109/epe.2016.7695307
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发表时间：
2016-09
期刊：
影响因子：
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通讯作者：
Ji Hu;O. Alatise;J. González;R. Bonyadi;L. Ran;P. Mawby
中科院分区：
文献类型：
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作者：
Ji Hu;O. Alatise;J. González;R. Bonyadi;L. Ran;P. Mawby
在高额定电流的功率模块中，需要多个器件进行并联，并联器件之间的电热平衡是一个非常重要的考虑因素。本文研究了并联器件之间的电热不平衡对并联对热稳定性的影响。正在研究的是并联的600V硅管脚和碳化硅肖特基二极管。通过设置不同的初始结温度和使用不同的热边界条件，即不同的外壳温度，引入了并联器件之间的电热不平衡。文中还对二极管工艺对互补晶体管热应力的影响进行了评估。结果表明，由于正向电流特性中较高的零温度系数点，硅PIN二极管工作在较低的结温下，而互补MOSFET的热应力较大，因为二极管的反向恢复会导致互补晶体管中的电流过冲。研究还表明，当碳化硅肖特基二极管并联时，在电热不平衡条件下具有更高的电热稳定性。与硅PIN二极管相比，具有不同初始结温度和不同热边界条件(壳层温度)的并联碳化硅肖特基二极管具有更好的温度收敛/稳定性。与Pin二极管对相比，并联SiC肖特基二极管对的温度收敛是由于其零温度系数(ZTC)较低，这意味着在并联的SiC二极管对中有更均匀的电流分配。
In power modules with high current ratings where several devices are required for parallel connection, electrothermal balance between the parallel devices is a very important consideration. This paper investigates the impact of electrothermal imbalance between parallel connected devices on the thermal stability of the parallel pair. Under investigation are parallel connected 600 V silicon PiN and silicon carbide Schottky diodes. The electrothermal imbalance between the parallel devices was introduced by setting different initial junction temperatures and using different thermal boundary conditions i.e. different case temperatures. The effect of the diode technology on the thermal stresses of the complementing transistor is also assessed. The results show that silicon PiN diodes operate at lower junction temperatures because of the higher zero-temperature coefficient points in the forward current characteristics, however, the complementing MOSFETs are more thermally stressed since the reverse recovery of the diode causes current overshoots in the complementing transistor. It is also shown that SiC Schottky diodes exhibit more electrothermally stable operation under electrothermal imbalance when connected in parallel. Parallel connected SiC Schottky diodes with different initial junction temperatures and different thermal boundary conditions (case temperatures) exhibit better temperature convergence/stability compared to silicon PiN diodes. The temperature convergence in parallel SiC Schottky diode pairs is due to the lower Zero-Temperature Coefficient (ZTC) point compared with the PiN diode pairs, which means more equal current sharing in parallel SiC diodes.