Non-Linear Error Analysis of the Variable Pole Pitch Capacitive Sensor
Ke Qin Liu, Mei Feng Zhang, Xuetao Pan · Applied Mechanics and Materials · 2012
The output characteristics of the variable pole pitch capacitive sensor is introduced, the relationship between non-linear error and range is analyzed respectively using theoretical fitting，zero-crossing rotation fitting and best uniform approximation fitting，theoretical expression is derived，and examples of calculations and MATLAB simulation are carried out. It has turned out that the expression based on the best uniform approximation fitting is more reasonable, having higher accuracy, and non-linear error is apparently reduced when the input of relative variation is the same; while in the given nonlinearity conditions, the range was significantly increased. To some extent, this provides theoretical guidance to the design and application of the variable pole pitch capacitive sensors.