Electrostatic sensors are used in the power generation industry to measure the velocity and other parameters of pulverized fuel. However, relatively little is known about the exact nature of the signal induced onto the sensor electrode, which is dependent on sensor geometry, particle size distribution, and particle velocity. This paper presents a novel approach to the study of signals induced onto intrusive electrostatic sensors, based on fitting a Lorentzian curve to the results of a finite element model of the sensor and pipeline.