| 摘要 |
[Problem] To improve fault detection performance with regard to a motor line voltage VR detection circuit for an electric power steering device, and maintain assistance using the electric power steering device even when a fault has been detected. [Solution] With regard to performing fault detection on a VR detection circuit through a correlation between a Vbat1 voltage obtained by a detection unit (Vbat1 detection unit) for detecting a control voltage from a control power supply circuit and a VR voltage obtained by a detection circuit (VR detection circuit) for detecting a motor line voltage from a power supply circuit, the VR detection circuit is provided in two systems (VR detection circuit (1) and VR detection circuit (2)) to provide redundancy and enable mutual comparison, making it possible to accurately perform a fault diagnosis on a VR detection circuit. Even when a fault is detected in both of the VR detection circuits, a diagnosis threshold value and/or a determination threshold value of the detection circuit is relaxed, making it possible to maintain assistance while restricting the level of assistance. |
