A method for controlling of the turn-off process of a voltage-controlled, gate-turn-off power semiconductors - switch and apparatus for carrying out the method

摘要

A method for controlling a voltage-controlled, gate-turn-off power semiconductors - switch (t1,.., t4) with a reverse - diode (d1,.., d4) and with a voltage clamping circuit (10) in the case of a diodes switching off with the following process steps:a) verifying whether the value of the gate - emitter - voltage (u_ge) - of the power semiconductor switch (t1,.., t4) is smaller than a threshold value (u_geth) - of the power semiconductor switch s (t1,.., t4) is,b) verifying whether the value of the collector - emitter of - voltage (u_ce) - of the power semiconductor switch (t1,.., t4) is smaller than a limit value andc) application of an auxiliary voltage (u_H) on the mos - control input (g) of the power semiconductors - switch (t1,.. t4) for a predetermined period of time, as soon as the aforementioned conditions a) and b) are fulfilled and a shutoff command (sig = 0) - for the power semiconductor switch (t1,.., t4) is present.