Effect of minor loop on magnetic characteristics of permanent magnet type of MRI

A modeling technique of the minor loop using typical hysteresis loops is shown. The effect of the minor loop and eddy current in the pole piece of a permanent magnet type of MRI on the residual flux density of the probe coil is examined. It is illustrated that the change ΔB of residual flux density occurs due to the minor loop of the pole piece. It is also pointed out that the choice of time interval Δt is important in a nonlinear analysis considering the minor loop