In order to solve the problems of weak anti-interference ability, low accuracy and poor real-time performance of the voltage sensor during measurement, a non-contact voltage sensor with a disc-shaped structure is designed in this paper. By adjusting the area of the spherical sensor plate, it presents a disc-shaped structure, so that the sensor can completely measure the electric field signal in the vertical direction, enhance the vector acquisition and analysis capabilities, increase the self-decoupling ability, and effectively use the electrode space. By establishing a finite element model, taking the three-phase overhead line as the excitation source and the sensor as the observation object, the feasibility of measuring the voltage with the disc sensor is verified. On the experimental platform, the disc-shaped sensor is tested for transient state, steady state and anti-angular deviation. The results show that the sensor can fully sense the electric field components in all directions, realize the collection and synthesis of the vector electric field, and have good decoupling The effect, effective anti-interference ability, meets the real-time and accuracy of measurement..