2-D modeling and characteristic analysis of a magnetic position sensor

This paper presents the shape design of the permanent magnet for a rotary type magnetic position sensor for an automobile acceleration pedal using a new two-dimensional (2-D) analysis method. Basically, its flux path is not uniform in the axial direction because the magnetic flux flows three-dimensionally (3-D) between the stator yoke and permanent magnet. So, the analysis and design of the magnetic position sensor has to consider the 3-D shape. We propose a 2-D analytical modeling method of magnetic position sensor account for fringing effects and optimize the shape of the permanent magnet for a high linearity characteristic. Then, the validity of the developed method is confirmed by comparing the calculated values with the measured values. Index Terms--Finite element analysis (FEA), fringing effect, fringing permeance, magnetic position sensor.