Electrical Engineering ⇒ Topic : Factors Affecting the Shape and Size of Hysteresis Loop

Factors Affecting the Shape and Size of Hysteresis Loop

There are three factors that affect the shape and size of hysteresis loop.

(1)The material. The shape and size of the hysteresis loop largely depends upon the nature of the material. If the material is easily magnetised, the loop will be narrow. On the other hand, if the material does not get magnetised easily, the loop will be wide. Further, different materials will saturate at different values of magnetic flux density thus affecting the height of the loop.

(2)The maximum flux density. The loop area also depends upon the maximum flux density that is established in the material. This is illustrated in Fig. (A). It is clear that the loop area increases as the alternating magnetic field has progressively greater peak values.

                                                       (a)                                                                               (B)

                                                                                          FIGURE

(3)The initial state of the specimen. The shape and size of the hysteresis loop also depends upon the initial state of the specimen. To illustrate this point, refer to Fig.(B). It is clear that the specimen is already saturated to start with. The magnetic flux density is then reduced to zero and finally the specimen is returned to the saturated condition.