The invention relates to the technical field of
copper rod detection, in particular to a
copper rod grain size detection method and
system based on double-frequency
eddy current analysis, and the method comprises the steps: synchronously obtaining a high-frequency
eddy current response
signal and a low-frequency
eddy current response
signal of the surface of a moving
copper rod according to an orthogonally arranged double-frequency eddy current probe, and collecting the
moving speed of the copper rod in real time; performing phase
demodulation on the high-frequency eddy current response
signal and the low-frequency eddy current response signal to respectively obtain a first
phase angle and a second
phase angle; calculating an instantaneous difference value between the first
phase angle and the second phase angle, and generating an original
phase difference characteristic quantity; performing dynamic compensation on the original
phase difference characteristic quantity based on the movement speed of the copper rod to generate a speed compensation
phase difference characteristic quantity; and inputting the speed compensation phase difference characteristic quantity into a pre-calibrated grain size mapping relation model to obtain a real-time grain size grade value. According to the invention, eddy current response interference caused by speed change in the continuous movement process of the copper rod is effectively eliminated, and high-precision detection of the grain size grade is realized.