Particle charging is a universal phenomenon due to the collision and contact between particle and particle, particle and wall in the powder pneumatic conveying process. The linear electrostatic sensor matrix (LESM) is able to capture the dynamic information of the moving charged particles in pipeline, whose spatial filtering characteristics has been employed to obtain the flow velocity of particles in gas-solid flow. The spatial filtering characteristics of LESM are closely related to its dynamic sensitivity (DS) distribution. In this paper, the 3D simulated model of the LESM was built by finite element method and the effects of its structural parameters on its dynamic sensitivity and spatial filtering characteristics were studied. The geometric dimensionless model of dynamic sensitivity of LESM was further established. Finally the experiment was carried out on a gravity-fed solids flow rig, and the experimental results was verified the simulation results.