| 摘要 |
A voltage detection section (11a) and current detection section (11b) detect a voltage and current supplied to a motor, and the detected voltage and current are supplied to a position detection section (12). An angular speed output from the position detection section (12) is supplied to a differentiator (13) to output an angular acceleration. A fundamental wave component extraction section (14) extracts a fundamental wave component of the angular acceleration, and the extracted fundamental wave component is supplied to an amplitude adjustment section (15). The output of the amplitude adjustment section (15) is subtracted from the average current command by a subtraction section (16). This subtraction result, current detection value, and the rotor position from the position detection section (12) are supplied to a current control section (17) to carry out the current control operation so as to obtain a current command. The current command is supplied to an inverter (4) to control the voltage and current so as to suppress the speed changing due to the load torque changing. Thus, stability is improved, and decreasing in cost is realized. <IMAGE> |
