| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a control device of motor-driven power steering device in which the low-pass filter characteristics of a current loop having a current feedback control system can be maintained constant in the whole current region irrespective of a change in the gain of the current vs duty ratio by a driving method using different duty ratios. SOLUTION: The configuration in which a power supply is connected between input terminals of a H-bridge circuit consisting of four semiconductor elements comprises a motor driving circuit 37 and a drive control means to drive a pair of semiconductor elements constituting two oppoing arms belonging to the H-bridge circuit, wherein the semiconductor element of a first arm is driven by PWM signals having a first duty ratio decided by the current control value while the semiconductor element of a second arm is driven by PWM signals having a second duty ratio, and the parameters of motor current control means 40 and 41 are generated so that a current loop frequency characteristic defined previously is obtained in accordance with the change in the gain of the PWM signals having the ratios the motor current vs the first and second duty ratios.</p> |
