Stator Winding Temperature Detection Method of High Voltage Motor Based on All-phase FFT

AC dehumidification drying is applied to the high voltage motor that is damp, and the temperature detection is beneficial to judge the insulation state of the motor. The stator winding impedance is obtained by measuring the voltage and current signal applied to the stator winding, and the temperature is calculated by the resistance extrapolation method. However, the traditional data processing method FFT spectrum analysis has a large spectrum leakage problem in the non-spectral line of voltage and current signal data. The introduction of all-phase FFT(apFFT) spectrum analysis can identify the original signal characteristic quantity with low error, and use FFT/apFFT phase difference method to correct the measured phase, amplitude and frequency. The test program designed according to apFFT can calculate the impedance of stator windings with high precision, which has a guiding effect on the practical application of temperature measurement.