In order to solve the problem that the voltage of a power voltage transformer changes with the fluctuation of the load for the power voltage transformer

a series compensation circuit of the auxiliary transformer is set up

which can realize the automatic regulation of the power supply voltage

but it will affect the error of the measurement voltage.Moreover

the error sources of power voltage transformer with auxiliary transformer series compensation circuit are analyzed. The analysis results show that

after adding series compensation circuit of auxiliary transformer

the error of measurement voltage consists of no-load error

load error

and auxiliary circuit error. On this basis

the error of a sample of 110 kV power voltage transformer with capacity of 60 kVA is measured. After the completion of load error compensation

the maximum variation of ratio error and phase angle error caused by the change of auxiliary circuit tap ratio are 0.462% and 73.14′. Through calculation

the value of auxiliary compensation impedance is obtained

and finally the error compensation under different tap ratios

different load capacities

and power factors is realized. After compensation

the error of the measurement voltage meets the requirements of class 0.2 error limit. The research of this paper realizes the error compensation of the power voltage transformer which has the function with automatic voltage adjustment. Under the condition of fluctuating load

the power voltage transformer can achieve stable voltage output and voltage measurement at the same time.