POWER CONVERTER UNIT CONTROL APPARATUS, ELECTRIC MOTOR CHARACTERISTIC MEASUREMENT METHOD AND PROGRAM FOR FINDING ELECTRIC MOTOR CHARACTERISTIC

摘要

Motor constants of an AC motor (3) are calculated to obtain rated torque current and rated excitation current as control constants necessary for vector control of the AC motor (3). An electric motor characteristic measurement unit (15) subjects a power converter unit (2) which changes voltage and frequency of electric power of an AC power supply (1) supplied to the AC motor (3) to control for changing a ratio of the voltage and the frequency. In first and second measurement modes, primary resistance, combined resistance and combined leakage inductance of the AC motor (3) are measured. In a third measurement mode, electric motor characteristic of the AC motor (3) is calculated from results of calculating excitation inductance, rated torque current and rated excitation current of the AC motor (3).