| 摘要 |
In a steering control apparatus (40), emergency switching elements (51, 52) constituted by semiconductor switching elements are provided respectively in a V phase and a W phase power supply line (42V, 42W) of a motor driving circuit (43). When an abnormality occurs, MOSFETs through which no current is flowing or MOSFETs through which a current oriented to turn a parasitic diode (51D, 52D) on is flowing are sequentially turned off such that all of the MOSFETs serving as the emergency switching elements (51, 52) are turned off. Thus, rapid current blocking is eliminated, and hence there is no need to use expensive MOSFETS that can withstand a spike voltage as the emergency switching elements (51, 52). As a result, a reduction in cost can be achieved. |
