Research of transmission delay test method in smart substations

For the sampling circuit of intelligent substation, more and more data conversion and information transmission links lead to an increase in sampling delay time, which is not conducive to the rapid and reliable transmission of information. This study analyses the mechanism of delay in the sampling loop of intelligent substation, and proposes an improved measurement method based on the detection delay of wavelet mutation point. This method can accurately measure the delay of the entire period in the sampling cycle in excess of one waveform cycle. Also, the correctness of the method is verified by simulation and field experiment.