| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inverter device that can properly grasp the highest temperature of a switching element by using a small number of temperature monitoring circuits without causing the upsizing of a device scale. <P>SOLUTION: In an inverter main circuit 130, a temperature detecting diode 140 and the temperature monitoring circuit 150 are arranged at only a fourth IGBT 132<SB>-4</SB>, and the temperature of the IGBT is monitored. When a motor 500 is brought into a locked state, the temperature of the IGBT being the highest temperature is estimated by using a controller 190 on the basis of an electrical angle of the motor 500, the temperature of the fourth IGBT 132<SB>-4</SB>that is detected by the temperature monitoring circuit 150, and thermal models of IGBTs 132<SB>-1</SB>to 132<SB>-6</SB>that are recorded in advance. The estimate of the temperature may be operated on the basis of a thermal equality expression, or may be calculated on the basis of differential data between the monitored temperature that has been detected in advance and the highest temperature. <P>COPYRIGHT: (C)2007,JPO&INPIT |
