IGBT device has the advantages of high current, simple gate drive, high-frequency performance and etc; therefore it gains widely application in the drive system of electrical vehicles. However, the current carrying capacity, cost and reliability limit its further application in the higher power level, such as 160 KW and further. One of the key technologies to overcome such limitation is the parallel connection of IGBT devices. This paper investigated the effects of some issues such as topological structure, gate drive resistance, snubber circuit and so on. The effects are verified by experiments and some important conclusions are presented.