| 摘要 |
PROBLEM TO BE SOLVED: To reduce the torque of a three-phase brushless motor caused by an error of an electric current detection system of an electric power steering device. SOLUTION: Electric currents Iu, Iv of the motor 3 are detected by an electric current detection circuit 14 after at least stand-by time based on a time constant of the motor 3 passes after a control signal of a duty ratio 50% is given to a three-phase electric current circuit 131 from a control part 155. An off-set electric current at this time is memorized as an off-set correction value in a correction value memory part 152. Additionally, a gain difference of detected electric currents iu, iv is detected, a gain correction value is computed by a correction value computing part 151, and the gain correction value is memorized in a correction value memory part 152. A driving electric current is corrected by correction circuits 141, 142 in accordance with the off-set correction value and the gain correction value at the time of normal action. COPYRIGHT: (C)2005,JPO&NCIPI |
