Why is hysteresis loss proportional to area hysteresis loop ?

In summary, when there is hysteresis loss, heat is generated due to the energy needed to redirect the spins in a material with ferromagnetism. This energy is proportional to the area under the hysteresis curve, which is determined by the horizontal axis of H and the vertical axis of B. This phenomenon is caused by the quantum-mechanical nature of the material, where there is an energy gap between a magnetized and an unmagnetized state.
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fxdung
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Why does hysteresis loss cause heat and why the heat proportional the area of hysteresis loop?
 
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Perhaps you can tell us what loop you are talking about: what's on the horizontal axis and what's on the vertical axis ? So what's the dimension of the area ?
 
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  • #3
The horizontal axis is H and the vertical axis is B
 
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Ferromagnetism occurs when it is energetically favorable that the spins of the electrons in the material are ordered in one direction and there's an "energy gap" between this magnetized state and the unmagnetized state. The microscopic reason that this happens in some few materials is quantum-mechanical. On the macroscopic level it's sufficient to know that this energy argument holds. This, however implies that to change the magnetization you need to do work to redirect the spins, and the change of energy is given by ##\int \mathrm{d} H B##, i.e., the area under the hysteresis curve.
 
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FAQ: Why is hysteresis loss proportional to area hysteresis loop ?

Why is hysteresis loss proportional to area hysteresis loop?

Hysteresis loss is proportional to the area of the hysteresis loop because it represents the energy that is lost during the process of magnetization and demagnetization of a material. This energy is dissipated in the form of heat, which is directly related to the area of the loop. A larger area means more energy is lost, resulting in a higher hysteresis loss.

How does the shape of the hysteresis loop affect hysteresis loss?

The shape of the hysteresis loop directly affects the hysteresis loss. A wider and flatter loop indicates a higher hysteresis loss, while a narrower and taller loop indicates a lower hysteresis loss. This is because a wider loop has a larger area, resulting in more energy being lost during each cycle of magnetization and demagnetization.

Is hysteresis loss the same for all materials?

No, hysteresis loss varies for different materials. It depends on the composition and properties of the material, such as its magnetic permeability, coercivity, and remanence. Materials with higher magnetic permeability and lower coercivity tend to have lower hysteresis loss, while materials with lower magnetic permeability and higher coercivity tend to have higher hysteresis loss.

Can hysteresis loss be reduced or eliminated?

Hysteresis loss cannot be completely eliminated, but it can be reduced by using materials with lower coercivity and higher magnetic permeability. Additionally, using laminated cores and applying an alternating current instead of direct current can also help reduce hysteresis loss.

How is hysteresis loss measured?

Hysteresis loss is measured by calculating the area of the hysteresis loop on a graph of magnetization vs. magnetic field strength. This can be done using specialized equipment such as a hysteresis loop tracer. The unit of measurement for hysteresis loss is joules per cubic meter (J/m³) or ergs per cubic centimeter (erg/cm³).

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