GATE CONTROL CIRCUIT FOR SEMICONDUCTOR SWITCHING ELEMENT

PROBLEM TO BE SOLVED: To ensure and facilitate overvoltage suppression gate control for suppressing heating of a switching element, and ensure and facilitate oscillation prevention and distributed voltage balance control in a semiconductor switch circuit comprising a plurality of switching elements connected in series.SOLUTION: Independently of a main gate current to an IGBT 1 applied through a gate resistance A by a gate drive circuit 2, a voltage-compensated gate control circuit 3-6 injects a voltage-compensated gate current via a gate resistance B when a collector-emitter voltage Vce of the IGBT 1 exceeds a threshold value, and stops injecting the voltage-compensated gate current when the voltage Vce falls below the threshold value. The gate resistance B is set to a lower resistance value than that of the gate resistance A. After the injection of the voltage-compensated gate current, a charge amount substantially equivalent to the injection amount of the gate current is drawn from the IGBT 1 as a gate current.