| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable detection of solder deterioration at a junction of an IGBT without considering environmental temperature.SOLUTION: A solder deterioration detection device 7 includes: a current detection part 21 for detecting an output current of an IGBT; a current increase determination part 23 for determining whether an absolute value of the output current is increasing or not; a cross point determination part 25 for determining whether the output current is at a cross point current value which is not influenced with temperature in a current-voltage characteristic of the IGBT if the absolute value of the output current is determined as increasing; a voltage detection part 27 for detecting an applied voltage to the IGBT if the output current is at the cross point current value; and a solder deterioration detection part 29 for detecting deterioration of solder, soldered at the IGBT, by determining whether the detected voltage is greater than a prescribed threshold value or not.</p> |
