Question

How do you plot a hysteresis curve?

Answer 1

Explanation:

Method to plot a hysteresis curve as:

1. The plot of hysteresis is known as a $B$-$H$ curve. Where $B$ (The material's flux density, measured in teslas or mega gauss) is plotted on the vertical axis and $H$ (The external applied magnetizing force, measured in amperes per meter) is plotted on the horizontal axis.
2. Hysteresis occurs in a system that involves a magnetic field. Hysteresis is the common property of ferromagnetic substances.
3. Generally, when the magnetization of ferromagnetic materials lags behind the magnetic field this effect can be described as the hysteresis effect. It relates to the magnetization properties of a material by which it first becomes magnetized and then demagnetized.
4. All ferromagnetic materials exhibit the phenomena of hysteresis.
5. The Magnetic Hysteresis loop above shows the behaviour of a ferromagnetic core graphically as the relationship between $B$ and $H$ is non-linear.
6. Starting with an unmagnetized core both $B$ and $H$ will be at zero, the point $0$ on the magnetization curve.
7. The $B$-$H$ curve follows the path as shown, as the magnetizing current flowing through the coil alternates between a positive and negative value such as the cycle of an AC voltage.

Hence the path shown above figure is called a Magnetic Hysteresis Loop.