| 摘要 |
PROBLEM TO BE SOLVED: To facilitate steering operations such as a steering operation during stopping in case a vehicle stops due to failure of a torque sensor, in an electric power steering system. SOLUTION: In case failure occurs in the torque sensor, when a vehicular speed V is 0 or below a predetermined value in proximity to 0 (namely, threshold value V0), based on a steering angleθand a steering angle velocityωwhich is a differential value thereof, in the case ofω=0 or|θ|≤α, a current target value It is set to 0 (S134), in the case ofω>0 andθ>α, to k(θ-α) (S142), in the case ofω>0 andθ<-αto -k(θ+α) (S144), in the case ofω<0 andθ>α, to -k(θ-α) (S152), and in the case ofω<0 andθ<-α, to k(θ+α) (S154). In a case where the vehicular speed V exceeds the threshold value V0, the current target value It is set in such a way that the current target value It is reduced at a predetermined descent rate to finally become 0 (S128). COPYRIGHT: (C)2003,JPO |
