The technique and application of phase measurement of operating voltage of the transmission line

The measurement of the amplitude and phase of the transmission line is the key technology which can monitor the insulated condition of all kinds of capacitive equipment or Zinc Oxide Arrester. However, it is short of the valid method measuring the phase of the transmission line in the outdoors. This paper puts forward a technology that can measure the phase of the tri-phase transmission line, to gain the voltage and the phase by the electric-field sensor, and finally achieve the phase of each phase transmission line through the method which can separate the phase from the superimposed electric-field. A lot of tests indicate that the phase precision can reach to 0.5 degrees. It can realize the insulation online monitoring of the capacitive equipment or Zinc Oxide Arrester by using the technology combined with the current transformer.