What are the characteristics of transformer magnetizing inrush current?

The magnetizing inrush current has the following characteristics:

1 The change of the initial phase angle of the closing has different effects on the three-phase excitation inrush current, and some phases are large, and some phases are small.

2 A non-periodic component containing a large component tends to bias the inrush current to one side of the time axis.

3 Contains a large number of high-order submarine wave components and is dominated by secondary submerged waves.

4 The excitation inrush current waveform has a discontinuity (the waveform is divided into zero currents in one cycle).

The purpose of full voltage charging is to check the internal insulation weak point of the operating transformer and to check the mechanical strength of the transformer and whether the relay protection device can avoid the magnetizing inrush current without malfunction.