| 摘要 |
<p>PROBLEM TO BE SOLVED: To detect an abnormality of a steering mechanism rapidly and surely by considering that the state where an excess current flow continues as long as the duration of the state where the excess current does not flow is less than a second threshold value once the excess current flows through an electric motor. SOLUTION: A main CPU 28 monitors an excess current detection flag by a predetermined cycle. When the excess current detection flag continues to be ON, a first counted value is incremented per predetermined cycle and when this first counted value reaches a first threshold value, a contact of a relay 36 is turned off and then, an electric current circuit from a power source to a DC brushless motor 17 is cut off. When the excess current detection flag is turned off, a second counted value is incremented. When the excess current detection flag is turned on again while the second counted value is less than a second threshold value, the second counted value is initialized, and after confirming that the first counted value is less than the first threshold value, increment is continued without initializing the first counted value.</p> |
