| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electric power steering device capable of exactly detecting an abnormality of a field effect transistor connected to a capacitor for smoothing in series. <P>SOLUTION: A motor driving circuit 13 for driving an electric motor generating steering auxiliary force in relation to a steering mechanism of a vehicle includes a bridge circuit 22 for driving the electric motor, power supply terminals tp and tn inputted with DC power from a DC power source for supplying DC power to the bridge circuit 22, the capacitor C1PC2 for smoothing interposed between a positive electrode line and a negative electrode line for connecting the power supply terminal and the bridge circuit 22, a field effect transistor FET2 connected between the capacitor C1PC2 and the positive electrode line so that a parasitic diode at the inside may have a direction for preventing accumulation of charge to the capacitor C1PC2, and an abnormality detection means 12 for detecting voltage between the capacitor C1PC2 and the field effect transistor to detect an abnormality of the field effect transistor. <P>COPYRIGHT: (C)2011,JPO&INPIT |
