Method to measure CVT transfer function

Summary form only given, as follows. In this paper the results of tests on a 275 kV and a 400 kV capacitor voltage transformer are presented. The objective has been to determine the transfer function of the CVTs in the Scottish Power EHV system, which in turn they can be used to compensate for errors at harmonic frequencies. As a primary requirement, the magnetic elements of the CVTs must be excited at nearly their nominal magnetic states. A test procedure is presented, which does not require CVT disassembling and/or modelling and ensures that the above essential requirement is satisfied. The effects of burden on the frequency response are also be presented. It is confirmed that the size and mature of burden affect the CVT frequency characteristic.