| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to design optimum static capacitance of a snubber capacitor and to reduce the static capacitance, in a power converting device comprising a self-arc-extinguishing semiconductor element connected in series whose critical rate-of-rise of OFF-state voltage is not regulated. SOLUTION: The static capacitance of a snubber capacitor 3 matches the largest one of static capacitances required to obtain gate drive power necessary for a gate drive circuit 15, to suppress the unbalanced voltage caused by the dispersion of turn-off time between GCT1 to a value equal to or less than a permissible value, and to suppress the maximum off voltage to be impressed to the GCT1 to a value equal to or less than a permissible value. |
