| 摘要 |
PROBLEM TO BE SOLVED: To provide an abnormality detection method for a semiconductor switching element, capable of detecting abnormalities without thermally affecting the semiconductor switching element and peripheral components.SOLUTION: The abnormality detection method for a semiconductor switching element includes, when turning ON a semiconductor switching element 2 electrically connecting and disconnecting a power source 1 and a load 4, the steps of: firstly detecting a power source voltage Vby a power source voltage detection part 3b; setting allowable time for turning ON tset which is a time not exceeding permissible calorific value P of the semiconductor switching element 2 when the power source voltage Vis applied; turning on the semiconductor switching element 2 only within the allowable time for turning ON tset continuously, and in the meantime detecting a load voltage Vld by a load voltage detection part 3c; and determining that the semiconductor switching element 2 is abnormal based on whether or not the detected load voltage Vld is a normal value. |
