In order to accurately measure capacitance and dielectric loss of a capacitive voltage transformer without disconnection

the author adopted a AI6000C dielectric loss bridge to analyze the testing methods for whole measurement without intermediate tap of a high voltage ratio CVT. It is concluded that taking the whole measure of CVT’s total capacitance and dielectric loss of C1

C2 in series to judge CVT is unscientific. Some specific methods are put forward to measure the C1

C2 capacitance and dielectric loss of 220 kV CVT respectively by using the method of self-excitation .