Research on the accuracy of measuring the permanent magnet servo motor performance by power factor

The stable operation of the motor is an important guarantee of modern industrial production. Therefore, it is important to quickly measure the motor performance and measure the stability of the motor. At present, voltage total harmonic distortion (THDv) and power factor are usually used to measure the motor performance. In this paper, a 3 kW permanent magnet servo motor (PMSM) is taken as an example to research the accuracy of this method. The 2-D transient electromagnetic field model is established by using its design parameters. The correctness of the model is verified by comparing the experimental data with the simulation data. Through the analysis of the influence factors of core loss, rotor eddy current loss and torque ripple, the mechanism of fast measurement of motor performance by power factor and THDv is obtained. It is found that THDv and power factor can't accurately measure the motor performance by calculating the motor performance under different conditions. On this basis, the influence of different harmonic voltage types on the air gap flux density distribution curve is analyzed, and the main reason of this method can't accurately measure the motor performance is found.