| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a vehicular steering device capable of controlling a motor as a drive source by a new control system without using any rotational angle sensor. <P>SOLUTION: A motor is driven by the γ-axis current Iγ of the γδ coordinate system which is an imaginary rotating coordinate system. The γδ coordinate system follows the control angle θC as the rotational angle on the control. The difference between the control angle θC and the rotor angle θM is the load angle θL. The assist torque T<SB>A</SB>according to the load angle θL is generated. On the other hand, the additional angle α is generated so that the steering torque T is fed back, and the steering torque T is brought close to the indicated steering torque T*. The additional angle α is added to the previous value θC(n-1) of the control angle θC to obtain the present value θC(n) of the control angle θC. The additional angle α is limited by an additional angle limiter 24. When it is determined that a steering wheel is controlled with no hands, the limit value of the additional angle limiter 24 is controlled based on the absolute value ¾YR*¾ of the target yaw rate by a limiter gain setting unit 43 and a gain multiplication unit 44. <P>COPYRIGHT: (C)2010,JPO&INPIT |
