Magnetic field interference suppression method based on phase-compensation vector resonance control in near-zero magnetic field environment

The traditional PI controller has limited ability to suppress magnetic field noise with high power spectral density and specific frequencies, leading to degradation in magnetocardiographic imaging quality. A phase- compensated vector resonance controller (PVRC) is proposed to suppress these disturbances. Firstly, by analyzing the coupling effect between the magnetic field and the ferromagnetic boundary of high permeability materials, the magnetic field response is divided into a first-order inertia link and a delay link. Then, the PVRC controller compensates for the phase lag of the disturbance in two stages. Additionally, the discretization method of PVRC is improved by replacing the cosine function with a Taylor series expansion to enhance response speed. The interference suppression effect of PI-PVRC is 27.5% higher than that of PI control.