| 摘要 |
PROBLEM TO BE SOLVED: To prevent misdetection caused by a capacitor rush current flown from a normal system when a power supply relay is turned on, in a power supply current monitoring device, after an overcurrent of a power supply current is detected once at one system of drive circuits of two systems, deciding a short circuit abnormality by repetition monitoring processing of repeating turn-on and turn-off of a power supply relay for the temporally abnormal system.SOLUTION: In repetition monitoring processing for a temporally abnormal system, after a power supply relay is turned on, when a prescribed number of monitoring cycles in each of which an accumulated time period of overcurrent time periods reaches a predetermined determination threshold Tj are consecutive, a power supply current monitoring device decides that the temporally abnormal system has a short circuit abnormality. The determination threshold Tj is set to be longer than a first overcurrent time Tc by a capacitor rush current Ic, and to be shorter than a sum of the first overcurrent time period Tc and a second overcurrent time period Tb by a battery short circuit current Ib. Thereby, the capacitor rush current Ic is excluded from a determination target for short circuit abnormalities, and the short circuit abnormalities are determined on the basis of presence or absence of the battery short circuit current Ib. |
