| 摘要 |
PURPOSE:To measure all required electric motor constants only under the conditions where an electric motor stops rotating without requiring a plurality of measurement conditions and unloaded tests. CONSTITUTION:A q-axis voltage command value is set to 0 by an electric motor constant operator 7, a primary angular frequency command and a d-axis voltage command are set to specific values, or a d-axis voltage command value is set to 0 and the primary angular frequency command and q-axis voltage command are set to specific values, and the signal is inputted to a coordinate converter 3 for converting to a three-phase voltage command, thus allowing current to flow from an inverter 2 to an AC electric motor 1. When the current is detected by current detectors 4a and 3b and is inputted to a coordinate converter 5, a d-axis current component and q-axis current component are outputted from the coordinate converter 5. Based on the output values and the above voltage command value, the resistance and inductance of the AC equipment are operated using two different primary angular frequencies, thus obtaining the constant of the AC equipment from the operation result of resistance and inductance for each frequency. |
