| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the following problem: two or more temperature elements are provided near both a switching element of an active converter circuit, which is a heat generating part, and a switching element group of an inverter circuit. <P>SOLUTION: A temperature rise of the switching element of the active converter circuit and that of the switching elements group of the inverter circuit have a relation with an input power supply voltage. Paying attention to this relation, the relation is obtained in advance and the temperature element is provided near either the switching element of the active converter circuit or the switching element group of the inverter circuit. Based on detected temperature of the temperature detecting elements, the input power supply voltage, and the relation obtained in advance, the temperature of each power element is estimated by a control microcomputer. If the temperature of each power element rises so much as protection is needed, the rotation of an electric motor is suppressed, a load is lightened, and the heat generation of each element is suppressed to perform protective operations against temperature. <P>COPYRIGHT: (C)2004,JPO |
