Measurement Uncertainty Sources Analysis and Verification of Time-Grating with Variable Coupling Coefficient

In order to improve the precision of Time-grating with Variable Coupling Coefficient, the electrical traveling wave equation was derived in detail base on the further study of working principle of Time-grating sensor. Combined with the processing and assembling methods of sensor, the uncertainty sources of sensor standing wave, synthesis traveling wave signal and the produce reasons of higher harmonic were analyzed by using uncertainty theory. The produce reasons of higher harmonic were verified with spectral analysis of the original sensor error data, and then the primary and secondary uncertainty sources affected the sensor measurement uncertainty sources were got, which were time and spatial orthogonal error, amplitude error of two roads signal and stator and rotor air gap uneven. The conclusion made in this paper can be used to conduct the structure optimal design, sensor error correction and uncertainty evaluation.