RCIESO based multi-source magnetic disturbance compensation method for magnetic shielding cylinder

Improving the signal-to-noise ratio (SNR) of magnetocardiography (MCG) signals holds significant clinical application value. In actual environments, the presence of multi-source magnetic disturbances can decrease the SNR of MCG signals, thereby affecting the SNR of MCG measurements. To tackle this issue, this paper innovatively proposes an improved extended state observer (ESO) with embedded repetitive control (RCIESO) for application in active magnetic compensation. The improved method includes two key steps: (1) enhancing the disturbance observation capability by incorporating correction terms into the traditional ESO structure; (2) embedding the internal model of repetitive control into the improved ESO framework to achieve excellent harmonic disturbance observation. Experimental results show that the proposed PI-RCIESO method effectively suppresses various types of magnetic disturbances and leads to an improvement in the SNR of MCG signals.