| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inverter device for a PWM control capable of shortening a time required for reducing heat loss of a switching element when a temperature of the switching element is increased. <P>SOLUTION: A device to perform a conduction control of a switching element 3 of an inverter 1 by a pulse width modulation signal having a carrier frequency comprises: temperature detection means 6 which detects a temperature of the switching element 3; a temperature comparison circuit 7 which outputs a first signal when a period in which the temperature detected by the temperature detection means 6 exceeds a first reference temperature lasts longer than a first prescribed period; and a carrier frequency control circuit 9 which adjusts a carrier frequency of an electric motor 5 driven by the inverter 1 to a stable limit value in accordance with the first signal output by the temperature comparison circuit 7. <P>COPYRIGHT: (C)2012,JPO&INPIT |
