| 摘要 |
PURPOSE: To so limit as to eliminate the voltage saturation and to execute the safe operation by providing a torque limiter for calculating the maximum capable of outputting torque calculated by a voltage equation by using a DC voltage, a speed estimated value and a motor constant at the torque current command value input terminal of a current control calculator. CONSTITUTION: A torque limiter 12 for calculating the maximum capable of outputting torque calculated by a voltage equation by using a DC voltage, a speed estimated value and a motor constant is provided at the torque current command value input terminal of a current control calculator 3. The limit value is previously obtained, and output, and a limit value is obtained by an approximate expression. Thus, the voltage saturation due to the DC voltage drop can be prevented, and the stable operation can be conducted. A limit curve is previously calculated off line and stored to conduct the stable operation by a simple method. Further, the stable operation can be conducted by the simple calculation by the equation for approximating the curve of the DC voltage-the maximum capable of outputting torque. |
