| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electric power steering device capable of performing torque control by a simple arithmetic processing using a synchronous reluctance motor having a nonlinear current-torque characteristic. <P>SOLUTION: Target torque is transmitted from an EPS control unit 41 to a motor control unit 51. The motor control unit 51 calculates a target current effective value I and a target current phase θ from input target torque. Here, switching of whether the calculated target current effective value I and the target current phase θ are calculated so as to obtain a maximum torque (a maximum torque obtainable with a minimum current effective value) or are calculated so as to obtain a maximum output (a maximum output obtainable with a minimum current effective value) is performed using a duty ratio of an output of a PWM conversion unit 57 comprising a three-phase inverter. Next, a three-phase to two-axis conversion unit 53 calculates a target q-axis current Iq and a target d-axis current Id from the target current effective value I and the target current phase θ, duty control is performed by the PWM conversion unit 57, and torque control of a motor 58 is thereby performed. <P>COPYRIGHT: (C)2010,JPO&INPIT |
