The capacitive voltage transformer（CVT）in operation is affected by the electrical filed of generated by the surrounding equipment due to its open type structure design. The participation of externally generated stray capacitance in the voltage division ratio of the capacitor unit leads to the deviation between the intermediate voltage and the design voltage and the offline error calibration data cannot directly reflect the actual operation error. In order to quantitatively analyze the influence extent of the surrounding electric field on the error of CVT

a finite element electric field analysis platform is established with the actual parameter of 500 k V CVT so to develop the simulation and analysis calculation on the influence extent of electrical field generated by the metal bracket

lightning arrester and high voltage lead on the error of CVT.Then

the simulation result is verified and analyzed in combination of real type test. Finally

it is known by analyzing and comparing the simulation data and actually measured data that external electrical field only affects the ratio difference of CVT and the electrical filed increase due to the surrounding equipment will lead to the increase of ratio difference of the CVT. The influence of variation of high voltage lead in the included angle

length and diameter on the ratio difference of the CVT is within 0.05%. This conclusion provides technical support for the analysis of CVT offline error test data.