초록 ▼

An active drive circuit for high power IGBTs provides optimized switching performance for both turn-on and turn-off by incorporating a three-stage action to improve performance characteristics. The gate drive circuit includes a semiconductor switch such as a MOSFET connected in series with a low res

An active drive circuit for high power IGBTs provides optimized switching performance for both turn-on and turn-off by incorporating a three-stage action to improve performance characteristics. The gate drive circuit includes a semiconductor switch such as a MOSFET connected in series with a low resistance gate turn-on resistor between the supply line and the gate input line, and a parallel connected bipolar transistor. During the first and third stages of turn-on, the MOSFET switch is turned on to provide rapid charging of the gate, whereas during the second stage the bipolar transistor is turned on to provide a controlled level of current charging of the gate. Similarly, a switch such as an MOSFET is connected in series with a low resistance gate turn-off resistor between the turn-off supply voltage line and the gate input line, and a bipolar transistor is connected in parallel therewith across the supply line and the gate input line. During the first and second stages of turn-off, the MOSFET switch is turned on to provide rapid discharging of the gate whereas during the second stage the bipolar transistor is turned on to provide a controlled level of discharge current from the gate.

대표청구항 ▼

[What is claimed is:] [1.](a) turn-on switch means for providing low resistance rapid charging of the gate of an IGBT;(b) turn-on controlled current means for providing controlled current charging of the gate of the IGBT; and(c) means for turning on the turn-on switch means to provide low resistance

[What is claimed is:] [1.](a) turn-on switch means for providing low resistance rapid charging of the gate of an IGBT;(b) turn-on controlled current means for providing controlled current charging of the gate of the IGBT; and(c) means for turning on the turn-on switch means to provide low resistance rapid charging of the gate of an IGBT during a first turn-on stage after receipt of a main command turn-on signal, means for turning on the turn-on controlled current means to provide controlled current charging of the gate of the IGBT during a second turn-on stage that follows the first turn-on stage, and means for turning on the turn-on switch means to provide rapid low resistance final charging of the gate of the IGBT to a turn-on voltage supply level during a third turn-on stage that follows the second turn-on stage and for maintaining the turn-on supply voltage level at the gate while the main turn-on signal is present.