| 摘要 |
PROBLEM TO BE SOLVED: To reduce turn-off losses, especially in driving operation. SOLUTION: A DC voltage of an inverter, constituted of a power semiconductor element like an IGBT, is detected via voltage-dividing circuits R4, R5. The detected output Vd is compared with a reference voltage by using a comparator CP1. When the output Vd is at most the reference voltage value, the rate of change of current, di/dt may also be low, so that the turn-off loss is reduced by turning on a switch S3 via an AND gate AN1, by making the gate resistance value of the IGBT as a parallel resistance of resistors R2 and R3 to reduce the resistance. |
