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This model is a 2D axisymmetric model of a homogenous multiturn coil with a permanent magnet core. A second ampere's law with pure and constant magnetization is used for the permanent magnet.

The study is a small signal frequency domain simulation, which is a two step static analysis followed by a frequency domain pertubation step at 20 kHz

In this model, there is signficant loss occurring in the permanent magnet domain, but there are no material properties that would account for such loss. The magnetization is constant.

Magnetic losses are calculated as

However, this seems like it may not be appropriate for this scenario. Plotting the H and B fields, its clear that this equation will generate loss given the plotting B and H fields, however I am questioning whether this equation is actually appropriate since there is no material mechanism here that will give loss. If the equation is appropriate, what is the physical explanation for the origin of the losses?

Also it should be noted that if the Magnetization is defined as Mz = 1.2 T, then the losses are actually negative, implying energy is being pumped into the system. If Mz is -1.2 T then the losses are positive but still unexplained physically.

Any help clearing this up would be helpful since I believe I will need to use a setup like this to simulate the losses and thermal characteristics of a system.