The measurement of the power system voltage is of important significance for energy measurement

the correct action of relay protection device and the monitoring of transmission line over voltage. We summarized several methods of on-line measurement for high voltage at present

compared and analyzed the working principle and characteristics of various measurement methods

and pointed out the existing problems of various methods. It can be seen from the analyses that the optical voltage measurement method has become a research hotspot due to its advantages of good insulation

small sensor volume

and good transient performance. The non-contact measurement method based on the D-dot principle has good development prospect due to its advantages of good insulation property

simple switching operation and being able to be replaced with electricity. However

the long-term stability of these two measurement methods still needs to be tested. At last

the development direction of high voltage measurement is prospected

which is beneficial to the practical process of the high voltage measurement methods.