| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent erroneous determination when any failure in a coolant temperature sensor is determined. <P>SOLUTION: PCU that converts supply voltage from direct current to alternating current and supplies it to a rotary electric machine has an IGBT element. The cooling water temperature Tw of cooling equipment for cooling the IGBT element is detected by a cooling water temperature sensor. In the cooling water temperature sensor, failure determination is carried out in accordance with the following flow. At Step S1, any failure in an element temperature sensor for the IGBT element is carried out. When the sensor is not out of order, the flow proceeds to Step S2 and an estimated value Twe of cooling water temperature is computed based on the IGBT element temperature Ts. When Twe<T1, or a first threshold, at Step S3, subsequently, failure determination for the cooling water temperature sensor is started at Step S4. The deviation between Twe and Tw is subsequently computed at Step S5 and this deviation is compared with T2, or a second threshold. When the deviation<T2 at Step S5, it is determined at Step S6 that the cooling water temperature sensor is normal. When the deviation≥T2 at Step S5, it is determined at Step S7 that the cooling water temperature sensor is out of order. When Twe≥T1 at Step S3, the failure determination for the cooling water temperature sensor is prohibited at Step S8. <P>COPYRIGHT: (C)2010,JPO&INPIT |
