| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a protective device of inverter that protects the circuit of an inverter, and allows an inverter with the same standard to deliver an uniform performance, by solving the problem that an inverter having a low thermal resistance, and a high cooling effect results in delivering a better output performance than an inverter having a higher thermal resistance and a lower cooling effect owing to individual differences even for the same product, and thus even an inverter of the same standard cannot provide an uniform performance. <P>SOLUTION: A protective device of inverter includes element temperature sensors (121, 108 to 113) for monitoring element temperatures Tj of at least one semiconductor chips, temperature correcting means (123a) for correcting the element temperatures Tj measured by the element temperature sensors based on thermal resistance of reference articles (thermal resistance of semiconductor chips of the worst articles in terms of deviations) that is an thermal resistance of predetermined reference articles, and thermal resistance of actual objects that is a thermal resistance of at least one semiconductors obtained in advance, and operation limitation determining means (123b) for determining whether or not an operation limitation of the inverter is required on the basis of values corrected by the temperature correcting means. <P>COPYRIGHT: (C)2007,JPO&INPIT |
