A new 4.5 kV-400 A module using SiC-PiN diodes and Si-IEGTs hybrid pair has been developed. The hybrid pair module is designed to realize high-frequency switching operation of high power medium-voltage power converters (1-10MVA, voltage range 310kV). In order to realize a low switching loss operation of the hybrid pair module, a hard gate driving with low gate resistor has been employed. Switching characteristics of the hybrid pair are evaluated experimentally and compared with that of a conventional 4.5 kV Si-IEGT and Si-PiN diode pair (All Si). The results show that the reverse recovery loss of diode and the turn-on loss of the Si-IEGT are reduced up to 95% and 60%, respectively. As a result, the total switching loss (i.e. turn-on and turn-off losses of the Si-IEGT plus reverse recovery loss of the diode) can be reduced up to 49% with the hybrid pair. The developed hybrid pair modules are applied to a prototype high power converter, and a high-frequency switching operation of 4 kHz has been successfully demonstrated.