With the characteristics of high sensitivity, high repeatability, high reliability, rotary variable differential transformer（RVDT）is also extensively used in the field of aviation electrical control, and the function is more and more powerful. In this paper. According to the working principle of RVDT and the finite element analysis software Maxwell, various structural factors affecting the differential output voltage of RVDT are analyzed and the simulation verification is completed. The analysis and simulation results show that the structure parameters such as the width of the primary coil, the width of the stator slot, the outer diameter of the rotor and the outer diameter of the rotor yoke have important influence on the output characteristics of the sensor. In order to study the changes of sensitivity of output voltage on the structure parameters, the weight analysis method of orthogonal experiment is adopted and the influence of stator slot width, rotor outer diameter and rotor yoke outer diameter is relatively large.