| 摘要 |
PURPOSE:To accurately and quickly measure the primary resistance of an electric motor by eliminating an error due to the difference in phase angle by calculating the deviation between a magnetization current command value and a magnetization current detection value and controlling a power conversion means as a magnetization voltage command value. CONSTITUTION:An adder 11 calculates the deviation between a magnetization current command value from a command value generation circuit 10 and the magnetization current detection value from a voltage current control circuit 16 and outputs the deviation to an adjustment circuit 14. When the deviation between the magnetization current command value and the magnetization current detection value reaches O, the output of the adjustment circuit 14 becomes equal to the actual value of a primary resistance. By multiplying the estimated value of the primary resistance thus obtained by the magnetization current command value by a multiplier 15 and adding the value to the output of an amplification circuit 13 with an adder 12, the magnetization voltage command value can be obtained. The magnetization voltage command value controls a power converter 3 via a voltage/current control circuit 16, thus obtaining the estimation value of the primary resistance without greatly being affected by the accuracy of the detector. |
